I suggest a Part 2, where you build 2 complete engines, identical except for the bore finish. Then put them on a DYNO to test power, compression, oil consumption, etc.
It wont work that easy... Tolerances matters. One will be done in minimum, second will be little bit looser but still in toleration and whole test would lie... :) But it's an intresting concept. I guess mirror finish will be better if You have some really hard shell like nicasil in BMW, otherwise honing will be better, living longer with same preformance.
@@KenjiDev There is a reason why cylinders have been honed for the past 100 years. Mirror finish gives the oil a hard time to stick and lubricate the pistons.
@@KenjiDev You could actually prepare bores with identical TOLERANCES, but different finishes. Different rings require different "RA" numbers. This determines the grit of the finishing stones. Achieving a "mirror" finish would entail using something much finer and smoother. But the final bore sizes could theoretically be made identical.
I want to see another tear down after 20 000 km. of daily driving. It appears 1000 km largely motorway driving wasn't enough to show the very small difference.
Back in the 80s, I rebuilt an engine in the parking lot. I hand honed my cylinders not knowing what I was doing. When I first started driving after the "rebuild", the engine was really down on power. It took about 1000 miles for the piston rings to seat and the further I drove, the power slowly increased.
Rings and especially diy honing tools have come a long way. Now a days a flex hone can give you a killer finish if you go roughly the right speed up and down, and make sure you clean them real good. Rings now a days don’t have any problem sealing
The problem there was that the bores don’t wear round, they wear into a tapered egg shape. Rings can’t follow those cylinder walls. Out of curiosity, was it a Chevy 350? They used soft cast iron like the Ford Windsors did, but had a taller deck height and longer stroke in the 389 and 302, so they don’t wear as much as the Chevy. The 351W’s were not as plentiful so I don’t have much experience with them. Maybe one a year would come into the shop.
I ran 5hp. Briggs and Stratton engines on a race kart. I would rebuild several with hyperotective pistons with zero gap rings and use them at my home and shop for a year to break in the rings. then tear them down come spring and put the billet rod,loose fit by .005 over stock. long poly oil flipper, tuff ride crank. It was amazing the difference then just honing, build, race…..
The homing effectively creates Labyrinth seals allowing oil retention that creeps back onto the aspirites where the reduced area metal to metal contact occurs between rings and cylinder. The unanswered question is how many km before all the bores present the same compression and what would the comparative ovality of bore look like? Higher compression would reasonably wear faster but might suffer increased ovality over the lower loaded cylinders in my estimation. Carbon build up would also lead to higher compression and reduce the equilibrium wear indication needed so maybe then do a decoke and check again would satisfy the conjecture nicely.....
Which is why engines need constant(ish) oil changes. Because the oil thickens over time. (There's ten replies about viscosity, go read those before replying.)
no matter what you have, though, without the crosshatch, there's no way for the oil to get up to the rings. And it rotates the rings to keep the wear even.
@@jwalster9412depends on the oil. I’ve seen thermal breakdown where the oil gets too thin to hold pressure in the pump. I’ve also seen some cars turn it to sludge. Toss up?
When i was young i used to hear guys talk about ' chrome plated rings ' taking a long time to ' break in '. I thought that sounded like it had to wear through the chrome plating and sounded dumb like it defeated the whole purpose of the chrome. I then had a 350 chevy short block to rebuild and miked it all out. It had mirror finish cylinders with almost zero wear so i thought i would try something. I installed chrome plated rings without touching the cylinder finish. When i had 7 pistons in i could still turn it over by hand on the crank weights. I didnt need a wrench until i had all 8 installed. I put it all together and it ran clean and fine right from the start. It ran well and at about 20,000 miles i drove it across country getting terrific gas mileage.
@@sp33drr it meant a lot to me. I used to watch friends rebuild short blocks and be lucky if it worked at all. For mostly backyard engine building I went on my own knowledge of engines plus a few ideas of my own and I drove my engine across country towing things. Sorry if I didn't have proper flow charts and proper records. I did mic everything and made sure all my rod caps were as ' round ' as possible. I was 21
@@solarsynapse There is way more to that, than simple ringed or not. ABC linears are chrome plated or made of chromium. Chrome is very hard and have low friction. They run on premix so lubricating oil comes from both sides. They run on high revs so blowby isn't big problem. Most important, they don't last very long.
the honed cylinders had less deposits on the valve than the polished cylinders. i was aware that you want to hone cylinders before installing new rings for best results, but it's nice to see it confirmed.
The two angle cross hatch pattern has two purposes. The first is to provide lubrication to the rings. And the steeper angle causes the rings to rotate to keep the cylinder wearing evenly preventing premature wear.
@@WhatsIncluded With an offset, gasses do not have a direct straight line to flow past the gaps, they do all spin a little, they don't spin the same amount, so after some time they would probably fix themselves at least a little, but it does help.
My understanding is that the honing serves 2 major purposes: 1) it traps oil against the cylinder walls for lubrication. The oil also helps the rings seal. 2) it helps the rings wear in when the engine is new (or fresh rebuild) and helps them seal better. A mirror finish would be better with a soft o-ring because the texture of the honing will shred the o-ring.
@@NotAnonymousNo80014 We need cars like this in the US. Our auto industry has let us down in a major way by putting their efforts into making cars that are needlessly expensive, difficult to repair, and that have features that are unnecessary, such as complicated audio systems.
@@NotAnonymousNo80014 Lada engines are built on very old porsche tech and Russians are quite experienced with metal casting. Lada's problems stem from poor fit and finish which are quite easily corrected if one has any idea how cars work. The other downside is they are quite uncomfortable to drive since everything is made simple as possible, no sophisticated undercarriage. Plus side is Lada's are pretty much bulletproof, you will always get from A to B.
As an engineer, trust me you need honing on the cylinder wall because of the lubrication, polished cylinders cause increased engine wear because the oil is not staying on the wall and lubricating it. That also worsens the thermals.
You talk about Teflon in a pan? Your ideal finish is probably sandpaper. Air presses past the rings through the drainage groves and pushed the oil onto the pan.
And what are you talking about, one time drag race ? Maybe for the extreme performance but if you want longetivity of the engine you need good lubrication and cooling effect.
@@patrickday4206 I learned that the lowest piston ring is there to remove oil from the walls. I guess that you could have a 4-stroke with a single piston ring and no lubrication problems. It would just drink a little more oil. Race engines have less rings because they get fresh oil before every race anyway.
Your guys do a fantastic job working on the engines you direct them to modify, I really like you and the channel, I wish there were as many old Ladas here in the USA, they seem to be really dependable reliable.
I swear these guys can read minds... I was wondering exactly this yesterday while thinking about sleeveless alloy engines (like Briggs and Stratton Koolbore) requiring a mirror finish in order to not eat themselves to death. I think it's a 2 stroke trait though, whereas a 4 stroke requires the honing to hold oil on the walls.
I knew the extention one because we did it at tech school. We put 16ft of extentions on a torque wrench and it was exactly where it should be. On the other hand, I did not know about the anti-seize. That's really good to know.
This was an interesting test. I suspect that the greatest advantages of crosshatch honing are: 1) Increased oil-film adhesion resulting in reduced cylinder corrosion during long periods of storage. 2) Increased oil-film adhesion resulting in reduced cylinder scuffing during startup, after long periods of storage. 3) Reduced piston-ring friction resulting in greater power and fuel efficiency. Reduced friction is partly due to oil adhesion, and partly due to reduced contact area and normal force. 4) Reduced piston-ring friction resulting in reduced coolant temperatures.
Back in the early 90s, I did a ring job on a 4 cylinder engine that had stuck rings on one cylinder and a cracked piston in another I honed the cylinders and after a week of regular driving, I took it for a 350 mile round trip that took about 6 hours. That engine never used any oil after that. It used half a quart during break in and that was all it ever used during the time we had that car.
I guess it does matter on what type of rings you're using . But the 22 degrees (roughly) is important for proper oiling . But a standard nodular quick seater ring will have a hard time getting a seat on a polished wall texture, where as a chrome ring will be more at home with a polished surface . I figured 1 and three would have a better time with oil control . I built a lot of engines over the years though . Good work guys . :)
I really like the off the wall ideas being put to test from this group!! Seem some stuff that you'd never think would work actually work! I bet this group can actually fix anything that thrown at them.
@@Skaadi89 Not if you're a professional lol. They use surface profilometers to measure the actual microscopic peaks and get the finish exactly how they want it. You don't want to have to break in a race engine cause now it's lost a bit more of it's already short life. You fire it up, check the tune, maybe check a two-step if you're drag racing, then you quickly shut it off. You want to run it as little as possible unless its actually racing.
I'M A MECHANIC HERE, and I know of a problem that Audi suffered by making the cylinders with a mirror finish, the lack of honed caused excessive oil burning in the engine of the Audi A4 sedan, a friend of mine who worked at Audi spent almost a year reworking these engines, dismantling and grunting and assembling these cars, and the results match the video demonstration, so it's decided that honed is necessary
@@midgetrace My dad's car with 250k miles still has it's cylinders honed in a cross pattern. Definitely went not away within breakin period, as they shouldn't
My Chevy 350 had 266k miles on it and when I took it to the shop they swore that there was no way it had more than 150k miles on it. Seven of the eight cylinders had the factory crosshatch and perfect compression. Only one was smooth on one side, where the head cracked and dumped coolant in the cylinder, thus the rebuild. All I did was regular oil changes with a good quality filter and high rated cheep oil every 3k.
@@rsemrad2 basically the smooth creates more carbon in the heads from the piston rings removing hundredths or thousandths of metal from the cylinder walls and themselves through contact. A smooth bore would allow equal distribution of pressure around the cylinders but momentum would mean the pistons have just enough wiggle room to touch the cylinder walls where as with a honed bore, you would have those pockets of unequal pressure filled with fluid and fluid is dynamic which means the pressure would force the oil into the low pressure pockets, thus creating a smaller area for pressure to build up and equalizing the pressure. In the smooth bore that pressure only sits in one area and is dispersed on the 3rd stroke instead of every stroke in the process. It means your rings will wear out faster and if there's blow by, then it's just as hard and as fast going the other direction as it is going in the intended direction
@@doopiej yes and as the brother explained, when your cylinders get hot enough, they’ll burn deposits away, which means those rings have a higher chance of failing in those cylinders
Honing is about durability not compression. It's main purpose is to create a film of oil under the piston rings in the valleys trapped.oil in Shiny cylinders will get wiped right away by piston rings.
The way ive been told about honong - you can only get so good of a machined finish. So adding in the cross hatching (in addition to letting it retain some oil during break in) allows the rings to essentially machine themselves to the cylinder - implying a mirror finish is what you're going for, but you'll never really achieve if you need specific tolerance
You are lucky, your dream car is easily achievable. For me it was the opposite because they only built 400 of my dream car. and it cost me waay more than its worth to get it here I even had to ship it from another country/continent. If I can do it so can you.
Depends on the ring package more than anything else. For best performance (and will use some oil): Typical cylinder bore finish readings of Pro Stock or Comp Eliminator, or NASCAR engines are as follows: Rpk 4 to 6; Rk 18 to 22; Rvk 18 to 32
I was watching the hydraulic press channel, where they were showing some huge bearings. It would be cool to see you guys fit those to a Lada to make some kind of wheel for it.
Dont support sexual changes, support ppl accepting how they were born. Thats what gender affirmation should be, not the inverted and harmful meaning deceptive ones use.
The honing holds a small amount of oil in the crosshatching. Compression is maintained with this. As in when loss of compression due to worn rings adding oil increases compression.
The polished cylinders will probably need around 10,000Km before rings seat properly. Honed cylinders will bed in rings faster plus, the 'scratches' allow an oil film to lubricate rings.
I think the differences have occured between the pistons because the honing and polishing was done by hand rather than on a machine. those slight variences are then multiplied by the thermo-cycling of the engine giving rise to those differences seen in the engine.
Carbon deposits don't necessarily come from burning oil. Gasoline is a hyroCARBON fuel. Incomplete combustion can leave carbon deposits. Too little air can make the engine smoke, right? Love the video!
There was a Fascinating video the other day on daves auto Centre RU-vid channel where they had a guy on discussing this exact topic. He's a specialist in the field and scan the bore after honing to see how many troughs it has for oil!
@@Dannysoutherner GM jumped the shark with that aluminum 140 cubic inch engine in the Vega. In 1976, they finally worked out the bugs and called it the Dura-Built 140 but, the car's reputation was toast at that point.
@@BlackPill-pu4vi I had a 77 Vega when I was a teen. It moved under its own power and price was right so it was a great car to me. Blew a head gasket, my fault. Fixed that and learned a lot along the way. My mom borrowed it one night and piled it up. Todays rolling iPhones I have no use for. Give me pre 90s any day.
@@JeffKopis Yes. The 2.0 Cosworth engine that did get put in the Vega has massive tuning potential. It was choked by the smog equipment of the time. Some car magazine (don't remember) desmogged a Cosworth Vega and that engine really woke up. New non-smog camshaft, fuel, timing, that engine's power really came out.
@@Dronohthrow that Lucas crap in the bin and just use fully synthetic oil. Modern cars don't like that thick goopy crap in their veins especially with the vvt engines and small bearing tolerances that Lucas stabilizer is just too thick. Might help an old ( pre 2000s) engine but keep that crap out of a modern engine.
Wellll, hone finish depends on the ring material. In the 1960s chrome plated rings were common. These required a fairly coarse cylinder wall finish to enable the rings to wear into the cylinder walls. On initial startup the friction was high and it may take 30.000km for the engine to break in. Then we progressed to a molybdenum infill in the top ring face. This required a smoother cylinder finish applied using finer grit stones. Now cylinder walls are initially honed with diamond stones of about 400 grit to about 0.0003" from final size. Then 800 grit stones are installed and 5 or 6 strokes are made to knock the high spots off the cylinder walls. The rings and piston skirts ride on the flat surfaces left while the deeper scratches hold oil to lube the skirts and rings.
Honed is good for break in as it's rough and allows for a custom piston ring fit and better compression faster thus isolating wear to the rings, you also use break in oil to do this for a small amount of miles. After you switch to normal oil. Polished I can see less resistance overall and a break in oil could still be used and logically speaking it may take longer but once the rings break in and you switch oils it should allow for a smoother run engine with minimal drag, but the difference would be very minimal as either engine with wear a pattern into the cylinder walls but on honed the rings will be formed faster but have more overall wear... Engine wise break in is the most crucial time and reducing the time spent in it is ideal(just like warm ups daily). I've rebuilt my race engine a few times and I think break in oil is a scam, just like I feel 8f warm up times being shorter us the goal, a moderate throttle run warms up the engine faster than a low load warm up and thus you get into efficiency faster. Honed vs mirror, I'd say mirror would be best if you drive a longer break in period while honed you drive much less and change oil. Either should be the same once you change oil to a good synthetic with plenty of zddp.
I've twice deglazed/honed motorcycle engines by hand with sandpaper. 100 grit perhaps. Quick to break in and never had any oil blowby. Just worked it at that same 40/45 deg angle. FWIW.
The fuel used is a big factor when it comes to the carbon buildup as well. The carburetor maybe running rich as well. Put 5km on the engine then recheck for the compression, oil consumption, and carbon buildup. Also check for even heating and cooling in the block. You may have cold spots or hot spots in the head and block
There’s a good reason we keep the engine’s and engine bay spotlessly clean in racing. If oil appears on anything we know where it is coming from leaks or spray. It’s all instantly apparent. Why not steam clean everything under the bonnet it’s cleaner to work on too. The last time I polished a cylinder by hand. I was 11 years old and knew no better it was on my 125 motocross bike. The only saving grace was I probably I didn’t do that good of a job. Honing traps minuet amounts of oil and stops wear on start up a tiny bit of 2-stroke in the fuel world be a good idea if you intend to polish the cylinders. I get why you would want to do it. Less friction equals a cooler engine so you can raise the Rev limiter and get more brake horsepower. But you become more reliant on the lube and would need to warm up the engine carefully. Because of the expansion and less cylinder surface oil Interesting I’d like to know what is the fuel. 98 octane. Or E5 E10 fuel. Does it have detergents or octane boosters maybe stabilisers. Scratching the surface. I would have tested with two different cylinder blocks took dyno readings after 1500 miles and then checked for wear. I think out of the two the polished would be best performance but show wear. And the honed slightly less performance but would have longevity. And that’s why the motor industry does it that way. But well done proper mechanics.
I always honed then cleaned with dawn dish soap with red scotch bright pad lightly just knock the edge off of the hone. I would bet the honed cylinders wore the rings more than the polished cylinders. All my engine rebuilds ran and lasted very long some of my tractor over hauls have over 25 years on them.
Honning is better only by the means that since in the tiny groves is always some residue of oil, it is much harder to seize the engine in extreme situations (like oil pump failure, overheating or so).
It really depends on the ring type as to what the best finish is for new ones on a good engine. Lake Speed Jr. of Total Seal has a few videos on this over on their YT channel.
Hone is preferable because of the peaks and valleys concept where, the oil has microscopic areas for lubricating the cylinder wall while on the mirror finish the base line all across the board. This will shorten the lifespan of the engine significantly
The hone marks or scratches hold small amounts of oil for lubrication and also help wear the new rings to exactly match the shape of the cylinder. A new engine would come with its cylinders finish honed, if that was a bad thing to do, the engine manufacturers would not do it. Keep in mind there are different grit honing stones, a less course stone is preferred for finish honing.
Rings will never seat with shiny finish. Usually your ring maker will say what hone to use. After watching, actually I am pretty impressed. Wonder how it would do long term.
My old mechanic used to dump VIM abrasive cleaner through the carby to rough up the polished cylinder walls on the new Ford Falcons in Australia 🇦🇺 in the 70ties.
Honing and new rings that can bed into the cylinder would be the better option in my guesswork, on top of properly seating valves as well, cos they can lose compression if they're not seating cleanly... :)
Honed bores, compression will be different with smooth bores and oil wont stay and id imagine more scratch damage would happen, I'm commenting before finishing watching the video. Good video so far
The honed cylinders allow for oil to remain in the very small grooves protecting the tv walls and rings. That’s it’s primary function. The mirror cylinder would be theoretically capable of a better seal but the friction would increase wear and shorten the life of the parts.
It all depends for what you use the engine,for racing and high performance engines they use mirror finish,for every day and for long lasting they use honed cylinders
Do a compression check. That is the best way to see if polished or honing is better.The way you guys polished the cylinders doesn`t mean they are round though. You can machine to a mirror finish if you have the right toolbit and the proper speed of the cutter.Honed cylinders keep a thin film of oil on the walls and this might keep the engine to last longer.
Only 2x very important reasons that I know for honing the cylinder, with new piston rings, 1= the honing in "cross hatching" patterns will wear the new piston rings into the exact shape of the cylinder, taking the rough casting edges off the rings to seal up and give better compression. 2= the honing in a cross hatching pattern will always pick up and keep oil on the cylinder, giving better lubrication and less friction and wear. but otherwise the mirror finish would be awesome if the rings were ground and polished to fit the newly machined bore exactly, like formula one engines.
I would say somewhere in between. the striations will hold oil in them giving them more lubrication and a honed cylinder won't hold oil as much but the friction between parts will be less anyways so honestly I think it might just be dependent on the kinds of loads you'll have on the car. For a torque motor honed might be the way to go for when you have to load up the engine and for higher rpm speed and racing applications it might also help to just have less friction in general and at that rpm you're def getting oil so really just might be on a case by case basis. With no extreme benefit one way or another without extensive testing with at least 20,000mi on each test.
There are a ton of video by some very successful people that cover this. I will paraphrase the industry standard now. Honing provides a texture for the oil to adhere to. Not only does it provide grip but distribution. The cross hatch allows the oil to cling and then be distributed as evenly as possible by the hydro dynamic forces at play. This presentation allows the rings to do the job of sweeping and sealing the contact points. If the walls are smoothe the pooling or capillary action and surface tension would negate the even distribution of oil across the entire sleeve surface and reslult in expected wear do to spotty lubrication. End rant. I have never in my life heard about this debate.. cool video and what ever that man driving cirlcles in the center of the track is getting paid, it is not enough 😂❤
Interesting video. Thank you. As I understand it, the valves with the honed cylinders were dirtier. Assuming I understand this correctly, the test suggests that the honing is working to do a better job of keeping the cylinder wall lubricated, but the tradeoff is that a little more oil is burned. Again assuming I understood the results, the honing vs. polishing question is about whether the slight increase in oil consumption in the honed cylinder is justified because the engine will run longer because of better lubrication.
Ok...Honing and ridge reamer ready...Semi Retired Mobile Mechanic/ Ex Street Racer..Combo of Tech Factory/Aftermarket/Promachist Shops is a great set of knowledge..Study all....
I know when I used to race the flathead Briggs & Stratton engines in go-kart racing We done a mirror finish..They would use oil but it didn't matter because it got changed after hot laps and then after the main race.. those guys claimed the engines would spin up quicker and turn more RPM.. and to help the compression seal they would drill gas ports in the top of the piston.. seem to work well..
Should have done a leak down test to see where the compression loss was going, past the rings or valves , which cylinders cleaned down past the rings more, honed or mirror.
A increase in Pressure is due to the oil being pumped into the chamber. it increases the compression by a lot. thats why 2 kept rising and 4 sky rocketed. Bruning to much oil means higher egt. A mirror finish is the worst you can do.
Vacuum leak causes the shake in the engine, yes I do believe the compression test, less friction, less cutting by the rings on the polished cylinders, but they will allow oil to pass by the rings on the highly polished cylinders. Increased compression because of less ring groves cut into the rings and cylinders.
