YES YOU NEED TO READ THRU THE LINKS THAT'S WHAT THEY ARE THERE FOR...AND THERE'S A GREAT DEAL OF USEFUL INFO IN THOSE LINKS,
This video is all about pistons, rings, and connecting rod installation.automotive engines diagnosis repair rebuildingautomotive engines diagnosis repair reb...
don,t get over whelmed, make a list and test adjust correct or replace each problem,
and check it off the list then move to the next issue,
its a finite list and theres not a damn thing on it you can,t accomplish,
with a bit of research, a few questions and this web-sites help
(a few tools the right attitude and a thick stack of cash would also be useful of course)
think carefully about both the initial cost and the structural strength of the engine block you select, the OEM blocks used in production car engines will RARELY accept a .030 plus over bore with out having one or more cylinders having marginally thin bore walls, this results in inadequate bore to ring sealing if its in the wrong area and promotes stress cracks. A .060 over bore in a SBC is rather commonly pushing that bore wall thickness up to or over a reasonable limit so you need to sonic and magnetically check the block for cracks and wall thickness.
you could easily dump $500-$ into machine work on a block that won,t last more than a few months under high stress if its not carefully checked PRIOR to the machine work being done.
there's a whole lot of info on the 632 CID BBC they go over, keep in mind that just because parts bolt up and you can spin the engine with a breaker bar, or the starter in no way means the clearance's are correct! the guys got about $20K-$25K or more in that engine and its basically wasted...
THIS BEAM STYLE TORQUE WRENCH IS THE TYPE TORQUE WRENCH YOU WANT TO CHECK ROTATIONAL RESISTANCE
yes it always helps too double check bearing clearances and take the time too verify oil passages are clean,
and bearing oil feed holes properly line up with the oil feed passages and verify,
those clearances, and not just simply assume, they are correct
, and assemble and re-verify those clearances.
Ok youve just installed your crankshaft in the engine block, with new main bearings and everything's well coated with assembly lube,and oil, and youve torqued down the main caps to spec. in at least three stages, and then gone back and rechecked the studs or bolts per the manufacturers...
This is (Episode 24) of the #ETCGDadsTruck Series.Link to (Episode 25): https://youtu.be/h7qowMqZXRALink to (Episode 23): https://youtu.be/HvVw2MKdUzcThis in...
Lake Speed Jr visits Jimmy Barton’s Hot Rod Garage to ask the question "how big should the ring end gap be?”Jimmy shares some some inside tips & tricks from ...
Theory into Practice
Now that we’ve covered the “why” of piston ring gapping, it’s time to put that knowledge to work. We asked DiBlasi for the main issues people run into, and he gave us some very practical advice, saying, “There are several mistakes people make when setting ring end gaps. I myself have done it in the past, so it happens to everyone. I will also address ring install problems in general…”
- Mistake #1 - Not setting ring gaps at all.“Some people think that the rings are pre-gapped and ready to drop in. Ring manufacturers have a pretty larger tolerance when it comes to the gaps right out of the box. Always place each ring in the cylinder you are going to set it for and measure. Keep that ring designated for the cylinder the entire time. Sometimes your cylinders are a few .in’s different from each other, so you will want to be consistent. I personally get zip lock bags and number each bag with a cylinder number. Those ring stay in those bags with the correct cylinder they belong in until I am ready to gap them, then go back into the bag until I am ready to install them one by one.”
- Mistake #2 - Not reading the suggested ring end gaps provided by the piston manufacturer.“Many ring suppliers only provide data on OEM ring gaps. Follow the ring gap instructions for the pistons you are using. Never use OEM ring end gap specs, as the material and applications are wildly different. We often get calls about people setting ring gaps to OEM specs which can be as little as 1/3 the amount of ring gap that’s actually required.”
- Mistake #3 - Putting rings in upside down or in the wrong location.“99% of every top and second ring set has a specific orientation. There are bevels, twist, coatings, and various other things that make rings directional. There is typically writing or a dot on all first and second rings that indicate which side is up. In terms of location, some pistons have the same thickness top and second rings. Pay attention to the shape and what each ring does so you know where it goes.”
- Mistake #4 - Gapping gaffes.DiBlasi breaks this down even farther, saying, “This is going to be a boring process with a lot of filing, counting, placing in the bore, measuring, and repeating.” It’s easy to get lazy or careless, but working cautiously and paying attention during this process is critical.
- Filing rings before initially measuring end gaps.“Some people assume the rings are already too small and start filing away without a baseline measurement. Always measure first.”
- Count your turns if using a manual ring filer.“This will help you understand how much material removed each turn on the filer equates to.”
- Not being aware of the material of the ring you are filing.“A steel ring is going to need significantly more turns on a ring filer to remove material than a cast ring. A steel ring might require 30 turns on the filer to yield .005in of gap increase, where a cast ring requires 10 turns. I made this mistake 10 years ago and filed an extra .020 from a cast ring and had to buy another ring…”
- Not squaring your end gaps off.“Make sure your ring end gaps are square and perpendicular to the cylinder wall surface. You do not want a taper, as the measurement of the end gap will not be correct.”
- Not taking your time.“This process is boring and requires back and forth measuring so you can be precise. Take your time and start filing little at a time. Once you are a few cylinders in, you will have an idea of how much each ring requires as far as turns.”
related info.
every part you choose is a compromise , and may require changes,
that cost you in time, money or performance to some degree,
and almost every part will require a bit of fitting or clearance work,
or adjustment to fit and function to get the best results
if it drops out of the package and bolts together as it drops out of the package,
its almost certain its not functional to nearly its full potential
your job is to think things through carefully and make sure parts fit and function to their full potential,
little things like checking piston ring end gap, verifying bearing clearances, and ccing the heads and checking piston to valve clearance, degreeing in the cam and verifying the valve train geometry, polishing combustion chambers, getting a decent 3 angle valve job,verifying the piston to bore clearance, MATTER's
http://garage.grumpysperformance.com/index.php?threads/bearing-clearances./page-2#post-
http://blog.wiseco.com/everything-you-need-to-know-about-ring-gap
http://garage.grumpysperformance.com/index.php?threads/bearings-and-oil-flow.150/#post-
http://blog.wiseco.com/engine-building-practices-you-need-to-know
http://garage.grumpysperformance.co...ed-holes-in-bearings-shells./#post-
http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools./
http://blog.wiseco.com/how-to-file-fit-and-install-piston-rings
From the February, issue of Circle Track
By Jeff Huneycutt
Piston Ring Prep
It can be a hassle filing...
read full caption
Piston Ring Prep
It can be a hassle filing three sets of rings per cylinder, but when done correctly the results can mean more power and less fall-off before the next rebuild.
Most of us consider piston rings little more than a necessary evil. That's probably because grinding rings is a time-consuming chore. And who hasn't accidentally ground a gap too large and wasted both time and money ordering up a replacement?
But when done right, piston rings can...
https://www.carshopinc.com/product_info.php/products_id//SPG1-12
read the links don,t skip them, youll likely save a great deal of cash and time knowing whats involved
http://garage.grumpysperformance.com/index.php?threads/block-prep.125/
http://garage.grumpysperformance.co...k-after-a-cam-lobe-rod-or-bearings-fail./
http://garage.grumpysperformance.com/index.php?threads/engine-block-cylinder-wall-thickness.976/
http://garage.grumpysperformance.com/index.php?threads/why-build-a-383-vs-a-350.715/
http://garage.grumpysperformance.com/index.php?threads/blocks-from-summitt-or-comp-products./
http://garage.grumpysperformance.co...s-why-doesn-t-anyone-ever-ask-or-check./
viewtopic.php?f=53&t=247
viewtopic.php?f=51&t=588&hilit=honing%E2%80%A6
http://www.bhjproducts.com/bhj_content/ ... pplist.php
viewtopic.php?f=53&t=
http://www.hastingsmfg.com/ServiceTips/ ... ishing.htm
http://www.enginebuildermag.com/Item/38 ... rings.aspx
viewtopic.php?f=69&t=&start=240
GET THE RING END GAP TOO TIGHT ,OR PISTON SIDE CLEARANCE TOO TIGHT,OR NOT PAY ATTENTION TO THE LUBE SYSTEM DETAILS,AND WHEN THE RINGS EXPAND WITH ENGINE HEAT THE ENDS TOUCH THE RINGS LOCK IN THE BORE AND THE PISTON LANDS SHEAR OFF, it RESULTS IN EXPENSIVE FAILURES GET THE GAP A BIT TOO LARGE AND YOU MIGHT BURN A BIT MORE OIL OR LOOSE SOME COMPRESSION, YOU'LL SEE A CHART LATER IN THE THREAD, BUT GENERALLY YOU'LL WANT .-. PER INCH OF BORE DIAM. FOR A RING END GAP
The truth here is that if the ring end gap is anywhere in the .016-.030 the rings will work out fine,
the piston ring manufacturer's know from testing that compression and oil control,
emissions and all other test results tend to show ring gaps under about .040,
have nearly zero effect on how the engine runs, how much oil it uses or its ability to pass emissions,
that .016 is the IDEAL end gap on a daily driver engine , remember as the pistons heat up the rings expand,
and the end gap narrows significantly. a .016 end gap should result in having the ring ends almost,
but not touch under normal operating conditions, almost all ring manufactures strongly suggest a bit larger end gap,
if you use any power booster , as that tends to noticeably increase operational heat and result in tighter end gaps. the piston alloy the fuel you use your fuel/air ratio and ignition advance curve all effect the engines operational temps, and as a result the true operational piston ring end gap.
keep in mind a piston even at only about 800 rpm,has a compression stroke 13 -14 times a SECOND, now get out your feeler gauge and look how thin a .030 feeler gauge is and remember the piston to bore wall clearance at operational temps is under .001, thus the potential end gap can,t potentially allow much flow through what is in effect a fast moving oil filled pin hole thats being slamed from bdc to tdc 13 times to 60 times per second depending on engine rpms
HONE WITH HONE PLATES to duplicate the stress the head bolts place on the cylinder walls to get a true round bore wall surface
use of a deck plate allows the head bolts to be torqued ,this duplicates the stress the heads when installed exert on the block and allows a much better ring seal
BORING and HONING a blocks bore are best done at a local machine shop where clearances and surface finish are more accurately controlled, BUT, IF your going to be honing the bores for MOLY rings I,d suggest a 240-280 grit hone a 45 degree cross hatch angle and a constant flow of flushing liquid washing over the stones and bore surface to keep the stones from clogging with micro grit trash, that gets removed from the high points in the bore surface.
Ive used both a flush of 90% diesel fuel mixed with 10% marvel mystery oil, as a flush and Ive used hot water with a couple teaspoons of dawn dish washing soap, both work, but I think the hot water and dawn solution produced the most uniform result, on the bore surface but that requires a good deal of cleaning and washing the block just like the diesel fuel mix as you darn sure want to remove all traces of grit and prevent rust forming from moisture so after hone work I power wash the block with a pressure washer,, flush the surface with alcohol paint thinner as it tends to get under and lift out micro crud and speed surface dry time ,then I spray it over with WD40 and heat it with a heat gun to remove moisture traces then re-spray it with WD, 40 [/b]
washing the blocks surface with alcohol, and drying with high pressure air helps dry a lock after a pressure washing
http://www.harborfreight.com/-watt- ... .html
http://www.circletrack.com/enginetech/c ... for_speed/
one factor I find amazing is how few guys realize that the rings MUST have space both above the ring and behind the ring in the piston grooves simply because its the hundreds of PSI of cylinder pressure that first forces the ring into the bottom of its groove then the pressure gets behind the ring and tends to expand it and hold it into the bore that is a huge factor in how effective the ring seals combustion pressure in the combustion chamber, if the clearances are filled with carbon build up the rings loose a great deal of there ability to seal.
ideally the pressure above the piston gets behind the top compression ring and increases the force holding the ring face to the bore surface, noticeably;y more than the ring tension alone can do.
http://www.sjdiscounttools.com/lis.html
measure carefully as the piston groove depth and back clearance must match the rings you use or youll have major problems
viewtopic.php?f=53&t=&p=#p
viewtopic.php?f=53&t=&p=&hilit=tool+groove+piston#p
viewtopic.php?f=53&t=509&p=632&hilit=tool+groove+piston#p632
viewtopic.php?f=53&t=&p=&hilit=ring+compressor#p
viewtopic.php?f=53&t=&p=&hilit=ring+back+space#p
yes thats a VERY commonly over looked factor, the chipping seeming to be sensitive to how aggressive I pushed the ring into the grinding wheel, and how agreasive the grit used is, the slightly higher cost diamond grit wheel IS worth the cost difference and how fast its spinning all effect results, even the direction the grinding disc spins effects the cut, it generally works best is the wheel , on the ring filer disc is rather smooth and the rings barely moved into the cutting disk with minimal resistance
BTW, most piston compression rings have a dot on the upper surface to indicate the side designed to face the top of the piston
http://www.tooltopia.com/fowler-72-646-300.aspx
https://www.youtube.com/watch?v=gjN0fGfUzl0&t=71s
https://www.youtube.com/watch?v=LcOHsZxuqAM&t=23s
yes as always theres cheap,functional, and theres expensive precision ring filers
http://www.abs-products.com/specialty-t ... nder.shtml
Indycars posted these GREAT PICTURES OF HIS RINGS UNDER MAGNIFICATION SHOWING THE MICRO CHIPS IN THE MOLY RING FACING
http://www.speedwaymotors.com/Precision ... ,.html
NOTICE the two totally different OIL ring scraper ring widths in this picture above,OIL RINGS come in dozens of designs so, you can not use all oil rings on all pistons and you can,t swap expanders and wipe rings thru different designs, and you must verify piston groove measurements , measure carefully as the piston groove depth and back clearance must match the rings you use or youll have major problems
http://www.summitracing.com/parts/SUM-/
http://www.muller.net/sonny/crx/rings/index.html
http://www.teglerizer.com/triumphstuff/75w_newrings.htm
http://www.summitracing.com/parts/PRO-/
http://garage.grumpysperformance.co...gine-project-dart-shp./page-12#post-
http://garage.grumpysperformance.co...g-and-installing-connecting-rods-pistons.247/
your going to need decent feeler gauges
if the ring gaps, or piston to bore clearances are not carefully checked, or not correct your engine could easily get screwed up
Due to machining tolerances on both pistons and bore sizes theres always some minor differences between components,
when your assembling any engine, youll file fit the ring gaps to individual cylinders,and youll,
generally you'll want to carefully measure each individual piston diameter and each individual bore diameter very carefully,
and match the larger pistons to the larger bore sizes to keep the average side clearance as consistent as possible
most applications would have a ring gap of about .004-.005 per inch of bore diam.
but tests have shown even a .050 end gap has only a marginal effect on engine power or blow by, simply because at even rpm theres slightly more than 8 power strokes per second, and the pressure is near max mostly in the 10 degrees before and 30 degrees after TDC, theres very little time to force much thru a .005 or less piston to bore clearance and two .050 end gaps even if that was the case
here is where you, or your machine shop can screw things up on ring to bore seal,Don’t get crazy trying to get the minimum end gap.
if you have a minimum possible end gap for the piston rings, they will not provide a significantly better seal than the correct or slightly larger end gap, do not push it to minimum spec. the saying goes like this: if the gap is too big nobody will know, but if it is too small everybody will know, be cause if the end gaps too small the ring ends touch, lock the piston in the bore, shear off the ring lands and destroy the engine, a but to large results in not much but a tiny bit more oil being used
Often filing rings is required, so be sure to clean the filed area with sandpaper to smooth the burr then wash with soap and water. Little horsepower is lost through the increased gap and what good is horsepower if your rings come together and break a piston or two
when you hone the bores,get and use block deck hone plates, during the hone process , keep in kind you want to use the same (STUDS OR BOLTS) the machine shop used and the same torque settings they used when the cylinders were honed with deck plates or the distortion of the bore and ring seal won,t be identical (exactly round)or ideal , ring tension helps seal the bore on the intake stroke but on the power stroke cylinder pressure forces the rings hard against the lower ring land surface, the space above and behind the ring is nearly instantly filled with hundreds of psi of cylinder pressure forcing the ring out against the bore wall.
think about this a second,before spending your cash on gap less rings.that can cost 3 times what standard gap piston rings do,
With the engine temps up to operational levels the ring end gap is generally in the .007-.005 range and actual piston to bore side clearance is in the .001-.002 range, that's not counting a film of oil covering and filling much of that remaining clearance,and piston temps that can easily exceed 400f , now consider that at even just rpm, theres 25 compression strokes per second, which are taking up 1/4 of that rotational time frame, so in effect, to get gas leakage past the rings you have to forced the compressed gases past two piston ring end gaps (FIRST AND SECOND COMPRESSION RINGS) located in a randomly staggered location, thru a pair of ring end gaps that are about .002 x.006, in less than 4% of a seconds time.
when they do those impressive leak down tests the piston and rings are stationary, not reciprocating at and changing between high cylinder pressure and several dozen inches of exhaust scavenging vacuum,25-60 times PER SECOND, like rings in a running engine, nor is the engine operating at anything close to operational temps and pressures
while theres zero doubt that the gap less rings in theory will seal a bit better,if properly installed, the real world advantages, are minimal during true operational conditions, because you can,t force much compressed gas forcing its way past the piston ,down thru a hole on a set of staggered ring gaps, over that very brief time frame, thru what is effectively the size of a hole in a needles eye.
watch this and read thru the linked info, posted below, there's only a few ways to screw up an engine rebuild faster than NOT having the rings installed correctly or gaped to match the application, and heat range.
run the ring gap too tight, and the ring ends touch and the ring can lock against the bore, frequently busting ring lands or pulling the top of the piston ring land clear off, resulting in,having chunks of busted piston ring land compressed into the quench area, or results in bent connecting rods and cracked cylinder heads, bent valves etc.
BTW when you go to buy a ring compressor....this type(ABOVE & BELOW) works far better than the others, but its specific to a very limited range in bore size applications
http://store.summitracing.com/partdetail.asp?autofilter=1&part=PRO-&N=700+115&autoview=sku
Proform $31
remember to dip the piston and rings in high quality oil just prior too or before assembly I,ve used MARVEL MYSTERY OIL FOR DECADES
https://www.summitracing.com/parts/sme-90a
https://www.summitracing.com/parts/sme-90a
https://www.summitracing.com/parts/sme-90a
https://www.summitracing.com/parts/tsr-rc-
https://www.summitracing.com/parts/tsr-rc-
having a decent set of piston ring compressors available in your tool box helps
make engine assembly far easier, using the type posted above makes the job rather easy
using the type below could make a preacher cuss up a blue streak
the #$%%^^& things are just prone to allowing rings too catch and potentially break, as they enter the bore, yeah they work at times but they are not nearly as easy or foolproof
https://www.summitracing.com/parts/lil-
this style ring compressor below has a nasty habit of not keeping the rings evenly compressed and not seating evenly on the block , Ive used them but the type above is much easier to use
http://store.summitracing.com/partdetail.asp?autofilter=1&part=PRO-&N=700+115&autoview=sku
http://store.summitracing.com/partdetail.asp?autofilter=1&part=SME-W&N=700+115&autoview=sku
http://www.sswesco.com/ss/sssugges.htm
viewtopic.php?f=53&t=
http://garage.grumpysperformance.co...gine-project-dart-shp./page-12#post-
http://www.babcox.com/editorial/us/us.htm
https://www.engineprofessional.com/EPQ2-/mobile/index.html#p=17
http://www.circletrack.com/enginetech/c ... index.html
http://www.kb-silvolite.com/article.php ... ad&A_id=56
http://www.wiseco.com/PDFs/Manuals/RingEndGap.pdf
http://www.stockcarracing.com/techartic ... index.html
http://www.riken.co.jp/e/piston/b/b_1.html
http://www.carcraft.com/techarticles/pi ... index.html
http://www.aa1car.com/library/ar293.htm
http://www.gmhightechperformance.com/te ... ation.html
http://www.aa1car.com/library//eb.htm
http://www.jepistons.com/dept/tech/dl/p ... rc.pdf
http://www.aa1car.com/library/ring_end_gap.htm
http://www.aa1car.com/library/ring_end_gap.htm
http://www.circletrack.com/howto//index.html
http://www.chevyhiperformance.com/howto/ch_file_fitting_pistons/index.html
http://www.popularhotrodding.com/en...em_building_the_short_block/piston_rings.html
http://kb-silvolite.com/article.php?action=read&A_id=56
http://www.sswesco.com/ss/sspow.htm
http://www.racetep.com/totalsealframe.html
http://www.cdxetextbook.com/engines/com ... rings.html
http://www.dragracingaction.com/index.p ... press=
http://www.federalmogul.com/korihandboo ... ion_18.htm
http://kb-silvolite.com/article.php?action=read&A_id=32
http://moodle.student.cnwl.ac.uk/moodle ... rings.html
you have the option of ordering slightly over sized rings and carefully file fitting the end gaps,
no mater what size rings or end gap , you use the rings will normally take 5-20 minutes or so to lap into and perfectly seat and fit the bore walls
obviously the closer they match the application on start-up the more rapidly you could expect that to happen.
remember a properly honed bore using deck plated helps the process a great deal.
http://garage.grumpysperformance.com/index.php?threads/finding-a-machine-shop.321/#post-
http://garage.grumpysperformance.co...ore-clearance-on-your-block./#post-
http://garage.grumpysperformance.co...on-ring-info-youll-need.509/page-2#post-
http://garage.grumpysperformance.com/index.php?threads/piston-to-bore-clearance./#post-
http://garage.grumpysperformance.co...plate-honing-makes-a-differance.588/#post-869
http://garage.grumpysperformance.co...ing-piston-to-bore-ring-seal./#post-
http://garage.grumpysperformance.co...ng-piston-ring-grooves-and-related-info./
http://garage.grumpysperformance.co...block-cylinder-wall-thickness.976/#post-
BTW I recommend THIS TYPE of piston ring compressor (below)as the type in the video can and occasionally does allow the rings to pop out and jam, or break far more frequently .
the picture lacks detail, but the interior of the compressors tapered, you tighten to a slide fit on the piston diam. and the rings compress fully as they are entering the cylinder entrance and only expand after entering the bore.
http://www.amazon.com/KD-Tools-850-Diam ... STSMG/
this type (ABOVE) handles many applications but the cheap versions are a P.I.T.A. to work with
Installing the pistons & rods into the engine block... Having fun with this Performance 454 BBC engine build, and the next step is to assemble the bottom end...
BTW when you go to buy a ring compressor....this type(ABOVE & BELOW) which is an adjustable diameter and tapered design, works far better than the others,
but its specific to a very limited range in bore size applications
so youll need to buy the correct matching size
http://store.summitracing.com/partdetail.asp?autofilter=1&part=PRO-&N=700+115&autoview=sku
BTW I recommend THIS TYPE of piston ring compressor (below)as the type in the video can and occasionally does allow the rings to pop out and jam, or break far more frequently .
the picture lacks detail, but the interior of the compressors tapered, you tighten to a slide fit on the piston diam. and the rings compress fully as they are entering the cylinder entrance and only expand after entering the bore.
BTW when you go to buy a ring compressor....this type works far better than the others
http://store.summitracing.com/partdetail.asp?autofilter=1&part=PRO-&N=700+115&autoview=sku
Proform $31
you'll be surprised at how much easier they slide into the bore if you BOTH pull/guide and push the pistons into the cylinders rather than just beat them in with a hammer handle, it takes some practice but a few taps to get them moving with a fist, while pulling and guiding the rod into its journal is usually all that necessary with a well oiled piston and that type of ring compressor.
IVE dunked my piston/ring assembly's in a can of MARVEL MYSTERY OIL just before installation with a ring compressor and have never seen the slightest indication of problems either on ring sealing getting the rings broken in, or on tearing the engines down later for inspections.
be sure you, measure EACH bore and EACH piston,
(CORRECTLY with the proper tools in the way the tool and piston manufacturers suggested)
and number them on an engine build sheet indicating the bore and piston diam.
from large to smallest on each and install them on each cylinder to get the most consistent piston to bore clearance's
yes the difference may only be a few ten thousands if the bores are machined correctly, but you'll get the best results , most consistent lubrication, best durability and less heat build up that might result in detonation issues that way. its the little things that add up to making a good durable engine assembly,
BTW check rod orientation, so the beveled sides don't fact the adjacent rods, and check the bearing clearances with plasti guage
piston to bore clearance
ok first some facts (1)cylinders will not be honed to true round as they will be in use with out the use of a deck plate to simulate and duplicate the bolt clamp stress on the cylinder walls, bores in blocks without a head or deck plate with the bolts or studs torqued to spec are not nearly the...
garage.grumpysperformance.com
don,t guess on clearances and journal surface
So I decided to buy a couple of worthless old 283s to learn how to build engines. If I acquire the appropriate skills, I'm going to build a torquey 383 out of the anemic '77 350 in my C30. It tows cars, but it doesn't exactly set the road on fire, if you know what I mean. Anyway, I bought two...
garage.grumpysperformance.com
ring gapping and basic piston ring info YOULL NEED
YES YOU NEED TO READ THRU THE LINKS THAT'S WHAT THEY ARE THERE FOR...AND THERE'S A GREAT DEAL OF USEFUL INFO IN THOSE LINKS, don,t get over whelmed, make a list and test adjust correct or replace each problem, and check it off the list then move to the next issue, its a finite list and theres...
garage.grumpysperformance.com
assembling and installing connecting rods/pistons
look closely at the connecting rods one edge of the main bearing are is beveled noticeably more than the other that beveled side faces away from the rod its paired with because it matches the slight radiased bevel of the crank journal many builder class pistons are designed to go in, in either...
garage.grumpysperformance.com
KEEP IN MIND
any ring compressor design you use regardless ,of the design MUST have its lower surface kept firmly in contact with the block surface and parallel to the bore to allow the rings to smoothly transition from the inner surface of the compressor to the blocks bore, and IDEALLY the compressor internal diameter will be marginally smaller in internal diameter that the cylinder bore the pistons sliding into from it!
youll be surprised at how much easier they slide into the bore if you BOTH pull/guide and push the pistons into the cylinders rather than just beat them in with a hammer handle, it takes some practice but a few taps to get them moving with a fist, while pulling and guiding the rod into its journal is usually all that necessary with a well oiled piston and that type of ring compressor, btw IVE dunked my piston/ring assembly's in a can of MARVEL MYSTERY OIL just before installation with a ring compressor and have never seen the slightest indication of problems either on ring sealing getting the rings broken in, or on tearing the engines down later for inspections
if you have oil ring expanders with the plastic bits,they are there to prevent you from over lapping the ends of the oil ring expander, theres some oil ring expander s that are vertical ,some horizontal, but all have the ends butt , none over-lap
btw heres typical detonation damage, and in this case, resulting from a bit of nitrous, that boosted the pressure, but the results would be similar on a high compression engine subjected to crappy fuel and high loads at high rpms without nitrous, notice the sugary/frosted appearance and rounded edges of the melted areas
Are hypereutectic pistons bad? Keith Black Pistons? Watch this video to prevent total engine failure on your build. *Tools Needed below*Please Like and Subsc...
damage to the ring lands can be caused by detonation or just the ring gaps set too tightly, if the piston shows no frosted appearance its usually the ring gaps too small, or excessive heat, to lean a mix, to much ignition advance,etc.
most applications would have a ring gap of about .004-.005 per inch of bore diam.
but tests have shown even a .050 end gap has only a marginal effect on engine power or blow by, simply because at even rpm theres slightly more than 8 power strokes per second, and the pressure is near max mostly in the 10 degrees before and 30 degrees after TDC, theres very little time to force much thru a .005 or less piston to bore clearance and two .050 end gaps even if that was the case
damage like this is rather frequently the result of the piston rings gap being too tight, the rings ends touch as they expand,
due to excessive heat and with no clearance the rings temporarily lock against the bore wall, the result is a broken ring, and fractured piston ring groove
obviously if you've been around engine rebuilds, long enough, your aware that you'll eventually see guys installing rings in piston grooves by spiral twisting them into place, like the picture below depicts
the 80MM-120MM tool fits almost all chevy V8 engines
the problem, with that method is that its not at all difficult to leave the piston ring twisted permanently,
or warping it to the point it either breaks ,
or its bent ,degrading its ability to seal against the bore wall.
yeah! I know all your buddies do it that way! its still a potential problem and has and will continue to cause problems
so its a good idea to carefully use a expander tool, but only expand the ring enough to install it.
http://www.summitracing.com/parts/shc-
these threads have good related info, that you should read thru before starting the block prep, and rotating assembly process
Id point out that measuring the combustion chamber seal at TDC , during a leak-down test, has the obvious advantage of easily duplicating the test results giving you a base line to compare the cylinders from, yet I'd also point out that you'll occasionally find the rings and valves do function correctly at TDC but the bore walls are not consistent in size and shape thus as the piston descends down the bore the rings tend to loose seal. cracks in the lower cylinder and out of round bores can in theory pass a leak down test done at TDC. Id also point out that an operating engine has combustion chamber pressure and heat levels that far exceed the test pressure and
the dynamic movement of the piston and ring to bore seal in an operational engine can be happening repeatedly ,from 450 to times a minute, and thats 8- 66 times a second
at a peak pressure frequently exceeding 600 psi,and temps easily approaching 450F or more clearances are far tighter than on a cold engine, which means the very reduced time factor, and far tighter clearance significantly reduce the volume of trapped compressed gasses getting out of the combustion chamber so a static test at 80psi-120 psi while helpful won,t tell the full story.
BTW heres a bit more ring info
http://www.federalmogul.com/korihandboo ... ion_18.htm
Rectangular Ring:
A piston ring with a rectangular cross section. This ring with its geometrically simple shape performs the necessary sealing functions under normal operating conditions. With a peripheral coating and appropriate barrel face the rectangular ring is today used mainly in the top groove in passenger car gasoline and diesel engines. Besides service in internal combustion engines, rectangular rings are commonly used as rotary shaft seals, e.g. transmission seals [1].
Taper Faced Ring:
Owing to the tapered running face the ring contacts the cylinder bore with its bottom outer edge. This shortens running-in and improves oil scraping. The gas forces acting initially at the running face provide a degree of pressure relief (especially when used in the top groove). Taper faced rings are chiefly installed in the second groove in passenger car gasoline and passenger car and truck diesel engines. In passenger car gasoline engines they are also used in the top groove.
Internally Bevelled or Stepped Ring:
By providing an edge relief on the top side of rectangular and taper faced rings a twist effect is achieved which, in all operating phases without gas pressure loading, brings the ring into bore contact only with its bottom outer edge while the inner edge contacts the bottom groove side (positive twist). This helps to improve oil consumption control. Under operating conditions the gas pressure forces the ring flat against the piston groove, creating an additional dynamic behaviour of the ring. Rings of this kind are used in the top and second groove of passenger car gasoline and passenger car and truck diesel engines.
Taper Faced Ring with Inside Bottom Bevel or Step:
In the installed condition this edge relief causes a negative twist, i.e. in the opposite direction to a ring with the relief on the top side. The taper must be larger than on a taper faced ring without twist or with positive twist so that the top outer edge is prevented from contacting the cylinder wall.
The effect of the negative twist is to make the ring contact the groove and create a seal with its outer bottom side and its inner top side [8]. This type of ring is installed in the second groove in passenger car gasoline and passenger car and truck diesel engines.
Keystone Ring:
A compression ring with a wedge cross section. With its tapered sides, radial movement of the ring in engine operation will cause the axial clearance in the groove to increase and decrease. This greatly reduces ring sticking, as the ring continuously works its way free of the combustion residues. These rings are designed with an overall side angle of 6° bzw. 15°, the larger angle being more effective against the tendency to coking. The keystone ring is used in the top groove in passenger car and truck diesel engines where ring sticking must be expected.
Half Keystone Ring:
A compression ring with only the top side tapered. Like on the keystone ring, the tapered side (keystone angle 7°) causes the axial clearance to vary as the ring moves radially, and thus reduces ring sticking. Owing to its asymmetrical cross section the ring has a positive twist when installed.
A half keystone ring is used in the top groove of passenger car and truck diesel engines when a rectangular ring is no longer adequate in regard to ring sticking but a keystone ring is not yet warranted. Another application is in 2-stroke gasoline engines, e.g. for snowmobiles and ultralight aircraft.
L-Shaped Compression Ring:
This ring is used mainly in small 2-stroke gasoline engines as a "head land" ring, the vertical arm of the L being flush with the top edge of the piston crown [9]. With gas pressure acting behind the vertical arm, this ring will also seal when in contact with the top side of the piston groove.
Besides being used in 2-stroke engines, in some cases it has been installed in automotive diesel engines in order to minimize crevice volume in the combustion chamber [10].
ALWAYS READ THE DIRECTIONS VERY CAREFULLY THAT COME WITH ANY ENGINE COMPONENT...ESPECIALLY RINGS
AS VARIOUS MANUFACTURERS HAVE VASTLY DIFFERENT DESIGNS
The Smooth Science of Cylinder Honing
BLOCKS SHOULD BE HONED TO SIZE WITH TORQUE PLATE SIMULATING HEAD BOLTS STRESS ON THE BORE WALLS
By Larry Carley
Larry Carley
The basics of honing cylinder blocks hasn’t changed much in recent years, but what has changed are the type of abrasives being used by many engine builders.
Silicon carbide and aluminum oxide honing stones of various grits have long been used in power honing machines and portable hones to finish cylinder bores. These types of abrasives are popular with engine builders because of their flexibility and low cost.
But in recent years, a growing number of performance engine builders and custom engine builders have started using the same type of honing stones that production engine rebuilders and OEMs use: diamond abrasives.
Conventional vitrified abrasives cut cleanly and do an excellent job of finishing cylinders – provided the right honing procedure is used to achieve a bore finish that meets OEM specs or the ring manufacturer’s requirements. But as the stones work the surface, they experience a lot of wear. In fact, the stones wear almost as much as the metal surface in the bore. Consequently, the honing machine operator has to constantly monitor the honing process and compensate for stone wear to keep the bores round and straight.
Tim Mera of Sunnen Products Co. in St. Louis, MO, says conventional abrasives require a balance between cutting action and stone life. As a rule, harder metals require softer stones. A softer stone requires less honing pressure, produces less heat and causes less bore distortion. So the bond that’s used in conventional abrasives is designed to wear quickly and expose the abrasives for good cutting action.
OEMs and production engine builders, on the other hand, don’t have the luxury of being able to baby-sit their honing equipment. Because of their higher production volumes, OEMs and PERs have to run their honing operations at higher speeds and with less operator supervision – which means diamond honing stones in most cases.
Diamond has long been the material of choice for high speed, high volume honing applications because of its excellent wear characteristics. Stone life depends on the hardness of the abrasive, the hardness of the substrate that holds the abrasives, the hardness of the engine block, honing speed, load and the amount of metal that’s removed. Diamond is the hardest natural substance known, so it can hold a cutting edge much longer than a conventional abrasive. This means the bond that holds the diamonds can also be harder because it doesn’t have to wear away as quickly to expose fresh stones on the surface.
Typically, a set of conventional vitrified honing stones might do up to 30 V8 blocks (240 to 260 cylinder bores) before they’re worn out and have to be replaced. A set of metal bond diamond honing stones, on the other hand, might do as many as V8 engine blocks (12,000 cylinder bores) before they have to be replaced. That’s a huge difference.
However, diamonds require a sizable up-front investment. A set of stones can cost $600 to $700 – which is a big jump from $15 to $35 for a set of conventional honing stones. Consequently, many small custom engine builders say diamonds are too expensive for their purposes. They also say they can’t afford to buy several sets of diamond stones to cover all the different bore sizes they do.
Even so, when the longer life of diamond stones is compared to that of conventional abrasives, diamonds may be more economical in the long run, even for a small shop (assuming an operator doesn’t overstroke a bore and break a stone!).
Pim van den Bergh of K-Line Industries, Holland, MI, says he sees more and more shops switching to diamond for a variety of reasons. "We were one of the first to offer diamond for honing machines because we saw its many advantages." He says it gives very consistent results with minimal stone wear.
Pros & Cons Of Diamonds
Because diamond is a harder material and wears more slowly than conventional abrasives, it cuts differently and requires more pressure. Diamond tends to plow through a metal surface rather than cut through it. This can generate heat and distortion in the cylinder bore if the wrong type of equipment, pressure settings or lubrication is used in the honing process. When done correctly, though, it can actually improve bore geometry by producing a rounder, straighter hole.
Diamond is also good for rough honing cylinders to oversize because it can remove a lot of metal fast. But finishing requires at least a two-step procedure. Otherwise, the surface will be too rough.
If you’re switching from conventional stones to diamond, you’ll generally have to use a higher grit to achieve the same Ra (roughness average) when finishing a cylinder. For example, if you have been using #220 grit conventional stones to finish cylinders for chrome rings, the equivalent diamond stones might be a #325 grit. If you have been using #280 grit conventional stones to hone for moly rings, the diamond equivalent might be #550 grit stones. The actual numbers will vary somewhat depending on the brand and grade of the stones.
A cylinder bore must have a certain amount of cross hatch and valley depth to retain oil. However, it must also provide a relatively flat surface area to support the piston rings. Ring manufacturers typically specify a surface finish of at least 28 to 35 Ra for chrome rings, and 16 to 25 Ra for moly faced rings. These numbers can be easily obtained with diamond stones and brushing, say those who use this honing technique.
One rebuilder we spoke to says he uses #325 grit diamond stones to end up with an Ra finish in the 20 to 25 range, which he feels is about right for moly rings. For some applications, though, he uses a #500 grit diamond to achieve a smoother finish in the 15 to 20 Ra range.
Final Finish
Something else that’s different when honing with diamond is what diamond does to the bore surface. Diamond tends to leave a lot of torn and folded metal on the surface, causing sort of a smeared appearance that doesn’t make a very good bore finish. Consequently, finishing the cylinder requires a second step to remove the damaged material.
One way to get rid of this material is to plateau the surface with a fine grit conventional abrasive (like a #400 or #600 grit stone). All that’s needed are a few strokes to shave off the tops of the peaks. But, the most popular method for finishing the bores when using diamond stones is to sweep the bores with a flexible brush or a nylon bristle plateau-honing tool. Brushing helps remove the torn and folded debris while improving the overall surface finish.
Chris Jensen of Goodson Tools & Supplies in Winona, MN, says, "there’s a lot of confusion about how to finish cylinder bores when using diamond. Since diamond leaves a lot of folded and torn metal on the surface, the bores need to be brushed to remove the debris. Many different names are given to the same tool and process. Some call it a plateau hone, a soft hone, a whisker hone or an ultra-fine hone. But they all do the same thing: they sweep across the surface to remove jagged peaks, folded and torn material."
Bristle style soft hones consist of mono-filament strands that are extrude-molded with a fine abrasive material embedded in the strands. The filaments can be mounted in different types of holders or brushes that can be used with portable or automatic honing equipment.
When finishing the cylinders with a brush, only light pressure is required. The rpm of the brush should be similar to that which the cylinder was originally honed, and no more than 16 to 18 strokes should be applied (some say 8 to 10 strokes are about right). Too many strokes with a brush may produce too smooth a finish that doesn’t hold oil.
Reversing the direction of rotation while brushing helps to remove the unwanted material on the surface. The end result should be a cylinder that provides immediate ring seal with little if any wear on the cylinder wall or rings when the engine is first started.
Sunnen’s Mera says, "brushing the bore after honing makes a huge improvement in the surface finish, whether diamonds or conventional honing stones were used to hone the bore. You can get the overall Ra down to 8 to 12, with RPK (relative peak height) numbers in the 5 to 15 range, and RVK (relative valley depth) numbers in the 15 to 30 range."
Equipment Requirements
Something else to keep in mind about diamond is that it works best in power honing equipment that has been designed to take maximum advantage of diamond’s honing properties. There are a number of companies that make diamond honing heads for use with various honing machines: Rottler, K-Line, Kwik-Way, Peterson, Winona Van Norman, Sunnen and others. But because of the increased loads, diamond may overtax some older power honing machines and increase the risk of stripped gears. It may be better to buy a new honing machine that has more horsepower and rigidity to handle diamonds.
"Most of our customers who hone with diamonds use a CK21 machine," says Sunnen’s Mera.
As for portable honing equipment, conventional abrasives are the better choice for this type of application. Most of those we spoke with say diamonds require too much pressure for portable honing equipment.
Another difference with diamond is the type of lubricant that’s required. A synthetic water-based lubricant is usually recommended instead of honing oil.
K-Line’s van den Bergh says, "water-based lubricants are easier and cheaper to dispose of than oil-based lubricants because they can be evaporated down to reduce their bulk. On the other hand, they occasionally require make-up water and have to be monitored to prevent bacterial growth.
"The type of lubricant you choose is very important because it can make quite a difference in honing performance. With conventional abrasives, you want a good quality honing oil. A lot of people run into honing problems because they’ve diluted their honing oil or tried to use something else like diesel oil or kerosene," says van den Bergh.
Anthony Usher of Rottler Mfg. in Kent, WA, says the OEMs all use long-lasting superabrasives with metal bonded honing stones. But the equipment and controls they use are very expensive, which makes it difficult to bring the same technology into a typical aftermarket job shop.
"About 12 years ago, we decided to change that. If new engines are originally honed with diamonds, why can’t we develop the same technology? So we set about developing honing equipment, controls and stones that would put the same technology into the hands of a job shop," says Usher.
"Diamonds last a long, long time. Because the stones don’t wear away, you can control the size of the bore more accurately," Usher explains. "This allowed us to build an automatic control system that allows us to size bores exactly the same every time."
Usher says for under $30,000, a job shop can buy a diamond honing machine that substantially reduces running costs and gives better results.
"The HP6A power stroking automatic honing machine is our newest product. It runs with diamond abrasives and has a programmable load control for both rough honing and finish honing. When it is finishing the cylinder, it automatically reduces the load because some cylinders have very thin areas that may distort if the load isn’t changed. The HP6A has a base price of $23,900 and a fully equipped unit goes for $28,000 to $35,000."
Plateau Finish Is Best
Regardless of what type of honing equipment or abrasives are used to finish cylinder bores, more and more shops are finding a plateau finish provides the ultimate finish.
A plateau finish is one that closely resembles a broken-in cylinder bore. When the bore is honed, the surface of the metal will have microscopic peaks and valleys. Peaks don’t provide much ring support, so as soon as the engine is started the piston rings start to scrub up and down and shear off the tallest peaks. As the engine continues to run, the peaks will be gradually shaved down until the cylinder bores are relatively smooth and flat (except for the valleys in the crosshatch that must be there to hold oil).
The normal engine break-in procedure will eventually produce a plateau finish anyway. But until it does, the rings and cylinders will experience unnecessary wear and the engine will experience increased blowby, oil consumption and emissions until the rings have seated – which might take several hundred or even several thousand miles to complete.
A better approach is to precondition the bore surface so the rings don’t have to "hone" the cylinders. A plateau finish will provide maximum compression right from the start, and eliminate most ring seating and sealing problems.
One recipe for achieving a plateau finish is to bore or hone to within .003Ë of final size. Then finish to final dimensions with a #220 or #280 grit conventional abrasive and follow up with half a dozen strokes of a #600 grit stone, cork, or a flexible brush or nylon bristle plateau honing tool.
If diamond stones are used, bore or rough hone to within .005Ë of final size. Then hone the cylinder to final dimensions with #325 to #500 grit diamonds, followed by six to eight strokes with a flexible brush or plateau honing tool. Many experts recommend leaving a little extra metal in the bore for final finishing if diamonds have been used to rough hone the cylinder. This is because rough honing with diamond leaves a very rough finish (over 100 RA depending on the grit of stone used).
Honing Hard Materials
In recent years, Nikasil coatings have provided a challenge for engine builders. Nikasil is a hard coating of nickel and silicon carbide about .Ë to .003Ë thick that is applied to cylinder bores to improve wear resistance. Invented by the German firm Mahle, Nikasil was originally developed for the Mercedes Wankel rotary engine. It has been used by BMW and Porsche in some of their engines, and is also used in many chain saw engines, some motorcycle and marine engines, and even many NASCAR Winston Cup engines.
Goodson’s Jensen says PERs have had success honing Nikasil treated cylinders with diamond. But for smaller shops that have only portable honing equipment, you can’t exert enough pressure with diamond to hone Nikasil. The best advice here is to use #220 silicone carbine and just do a couple of strokes to deglaze the cylinder. If a cylinder has to be bored to oversize, cut it out with a boring bar and then hone in the usual manner to achieve the desired dimensions and finish.
Ed Kiebler of Winona Van Norman in Wichita, KS, says new harder coatings on cylinder walls are forcing shops to change to diamond honing and to upgrade their equipment.
"I see a lot of shops who are interested in diamond but who don’t fully realize what’s involved in the diamond honing process. Diamond takes a lot of pressure to cut. Some people use diamond on portable hones, but realistically you can’t get enough pressure to make the diamonds perform well. Having said that, I truly believe the new harder cylinder coating materials are going to force people to go to diamonds," says Kiebler.
"The two-cycle stuff is all Nikasil. Now the outboard engines are going to Nikasil, too. All the NASCAR Winston Cup shops are using Nikasil cylinders. If it’s good for NASCAR, it’s not going to be long before you start seeing it in OEM engines," Kiebler explains. "The time is coming when you’re going to have to use diamonds if you’re going to hone Nikasil cylinders."
Kiebler says all most shops do is slightly roughen Nikasil cylinders. "You don’t really remove much material. The Winston Cup shops are running some of these motors five races before they redo the cylinders. The Nikasil coating really extends ring life and cuts down on ring wear."
OEM TRENDS
Dave Riley of Gehring L.P. in Farmington Hills, MI, a supplier of honing equipment to original equipment manufacturers, says almost all OEM internal combustion gasoline engines in North America today are being rough honed with diamond abrasives.
Riley says the OEM focus is on using water soluble synthetic honing coolants, which means diamond abrasives because vitrified conventional abrasives require honing oil. The other industry trend he sees is that cylinder bores are being respecified to smoother finishes.
"We’re talking 0.15 to 0.3 Ra finishes that are extremely smooth," says Riley. "They’re doing this to further reduce emissions. A lot of this is being driven by ring technology because rings can now survive in conditions that provide much less oil. However, in my opinion these new surface finish specifications are reaching the limits of technology."
One of the things that the OEMs do to achieve high quality bore finishes is to use computer numerically controlled (CNC) honing machines. The cutting speeds of these machines are 50 to 75 percent faster than what was used 10 years ago. Faster cutting speeds allows the abrasives to cut smoother, and finer abrasives can be used for a smoother finish without sacrificing cycle time.
Riley says there’s a dramatic difference in the amount of time the OEMs allow to hone a cylinder versus what a typical aftermarket engine builder or production engine rebuilder spends on the same process. He says OEMs typically spend only about 15 to 20 seconds to hone a bore with automated honing equipment. By comparison, it can take up to several minutes to manually hone a bore using a power honing machine.
"The OEM machines are completely automated and automatically control bore size and shape. They also measure and inspect 100 percent of the bores, and can sort by bore size if they run bore grades," he says.
"As the need to reproduce OEM finishes in the aftermarket grows, so too will the demand for honing equipment that can meet these specifications. This will obviously have an impact on honing costs," Riley explains. "We are developing a low cost, CNC-controlled single spindle honing machine for the aftermarket. The operator would load the block and the machine would automatically hone the bores to OEM tolerances."
Riley says Gehring also offers custom honing services for low volume engine prototype development and performance engines.
Cylinder bore quality plays a huge role in reducing friction and blowby for improved engine performance and durability. Better bore geometry also contributes to better sealing and more usable power. Riley says a lot of performance engine builders are hot honing their blocks to more accurately simulate actual running conditions. They also use torque plates when honing (some with simulated manifolds to further stress the block), and may even bolt a bellhousing to the block to reproduce the stresses and loads the block will experience in a vehicle.
"For OEM production applications, we have developed clamping and other methods to stress the block while it is being honed," says Riley. This is done to further improve bore geometry and sealing.
Aluminum Engines Soon
Riley says another OEM trend is the development of future engines that use various types of bore surface coatings in aluminum blocks. The coatings are sprayed-on powder metal or steel wire alloys that create the surface characteristics of a traditional iron bore.
"Last year, about 15 percent of the prototype engines we saw had some type of coated aluminum bores. This year, the percentage is up to 67 percent. So there has been a dramatic shift toward aluminum blocks with coated bores."
Coated aluminum bores have a number of advantages, one of which is better thermal conductivity between the cylinders and water jacket. Another is less heat distortion for better sealing. The coating provides wear resistance and allows the use of larger bores within a given block size for more total displacement.
Riley says the OEMs are currently acid etching the bores to finish them. But acid is environmentally unfriendly so the OEMs are developing alternative ways to finish coated aluminum bores that do not require acid etching. Diamond honing is used for roughing, but the finishing step is being done with nonmetallic bonded abrasives such as vitrified abrasives, rubber or brushes. The goal is to come up with a process that will work using water-based honing fluid.
How will the aftermarket refinish coated bores in aluminum engines? Riley says the most likely approach will be to hone away the original bore finish, then reapply the surface coating and refinish it back to OEM specifications.
Laser Structuring
A number of years ago, Gehring developed a unique process called "laser structuring" to enhance engine durability. The process uses a laser to burn small pits into areas of the cylinder bore surface where ring loading and wear are highest. The pits improve oil retention and ring lubrication, and significantly reduces ring and bore wear.
Riley says the new laser structuring process is now being used in Europe on diesel engines. "At 150,000 kilometers, the bores are showing almost no measurable wear (only 1 to 2 microns) and the emissions performance is the same as new," he says.
Riley says the laser structuring process can be used to create almost any kind of pattern imaginable in the bore surface. Typically, a series of dots or dashes 25 to 60 microns deep and 40 microns wide are burned into the top third of the cylinder by the laser after the bore has been semi-finished. A final honing step is then done using fine stones to remove any buildup of material around the pits and to finish the bore.
The laser part of the process takes about 9 to 15 seconds per cylinder and uses a special machine that rotates and lowers the laser beam as it is projected onto the surface of each cylinder.
Riley says the laser structuring process is ideal for hard blocks or those with special surface coatings that make them difficult to finish with conventional honing techniques. "It’s a perfect application for high performance, diesel and aircraft engines," he says.
Remember To Clean The Bores
As we wrap up this article on honing abrasives, one final point to remember is the importance of cleaning the bores after honing. Honing leaves a lot of metallic and abrasive debris in the bores – which must be removed before the engine is assembled. Washing and scrubbing with warm soapy water will remove most of the loose debris. Some engine builders follow up by wiping out the cylinders with automatic transmission fluid. The point is get the cylinders clean so there are no contaminants to damage the rings or to get into the oil.
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WHY DIAMONDS ARE SO EXPENSIVE
If you’ve balked at the high cost of diamond honing stones, here’s a brief explanation why they’re so expensive:
Diamond is a special form of carbon that is formed naturally under extreme heat and pressure deep inside the earth. As such, it isn’t very plentiful or easy to find. Subsequently, man-made synthetic diamonds are mostly used for industrial abrasives.
Scientists realized that if they could duplicate the heat and pressure that formed natural diamonds deep in the earth, they could transform ordinary graphite (another form of carbon) into diamond. They estimated it would require temperatures in excess of 6,300 degrees F and pressures of approximately one million pounds per square inch to make the transformation occur. But as the scientists discovered, it wasn’t so easy. Try as they might, they couldn’t get graphite to change its crystal structure and become diamond – until General Electric researchers discovered the secret in .
A catalyst was needed to make the change happen. The catalyst turned out to be a mixture of molten iron, nickel and cobalt. The various proportions of ingredients in the catalyst are still a closely guarded secret, so only a couple of companies in the entire world have the expertise to produce synthetic diamonds. In the U.S., synthetic diamonds are produced at GE’s plant in Worthington, Ohio. Several years ago, we were given a plant tour – but nobody except a trusted few are allowed to see inside the room where the diamonds are actually made.
GE says they can create different types and sizes of synthetic diamond for various industrial purposes by varying the temperature, pressure and type of catalyst. Man-made diamonds typically have a yellowish tinge and are as small as grains of sand. Even so, they’re ideally suited for their intended use as an abrasive. They’re just as hard as natural diamonds and actually perform better because of their custom-tailored shapes and characteristics.
Standard cast iron works but wouldn't be my choice
Moly rings are best if your machinist knows how to hone for them.
Chrome rings are old technology for when roads were dirt and air filters were not as efficient as today. I don't use them as they are more difficult to get to seal up and wear the block.
Most of our Studebaker vendors carry all three.
As to brands, in standard rebuilder rings, there really isn't a lot of difference. The Studebaker 3." bore is shared by the Chevy 194" and 235" 6-cyls, so they'll always be available from most manufacturers, even if they don't have a Studebaker listing any longer.
jack vines
I would probably go with moly, and hone the cylinders with 400 grit. Unsure about longevity, but moly is a coating that provides a quick seal, with minimum friction; it is available on both chrome and cast rings. At east that's what my favorite machinist (now deceased) said when offering me choices for rings on the last 352 Packard motor I rebuilt. The 352 uses small block GM rings, so modern choices are available. The last 352 I rebuilt used "Chromoly"; they seated quickly, and when I switched over to Mobil 1 after a couple thousand break in mile, there was no problem. They are the most expensive.
As for regular cast rings, if the cylinders are honed with 320 grit, they seat fairly quickly, but will usually wear out in 75,000 miles or less. But they are soft, and easy on cylinder walls, so you'll likely be able to just re-ring the motor in 50,000-75,000 miles. I used them once, and will not use them again. But if you do not foresee many miles on your car, they cost the least.
Chrome, on the other hand, seats best if honed with 220, and even then takes 5,000-10,000 miles to seat. Once seated however, they are good for 100,000 plus miles; the payback is that they are hard, and wear out (cut) the cylinders, so you'll likely need oversize pistons the same time you need new rings. The last 289 motor I rebuilt (finished last April) got chrome rings. I swapped over to Mobil 1 after only a couple of thousand miles, and it was too soon (excess blow-by). I recently hit 10,000 miles on the motor, and just swapped over to Mobil 1 again, this time no problems with blow by. They are mid-priced, between moly & cast.
As JV mentioned, all the above are available from our vendors.
Jack. Thanks for the note about chev rings being the same I've been going to get out the books and see if anything else would fit. I guy should be able to buy two sets of chev stock rings from a jobber and still save a lot over what they want for stude ring sets.I know when my dad had his rebuild shop in the mid 90's I could get rings from him at cost in cast for about $15-20 per set and their good rings. He brought detriot gaskets for small block ford and chev for under $15 a set.