87mm pistons in a f22 without sleeving

[wed3k]

I want to try this. the iron sleeve is about 125 thick or 1/8" at 85mm

so ideally, a 87mm piston would make the iron sleeve about .085". the aftermarket dart B20 block with a 84.5mm piston has thier sleeves at .060 granted it might be made out of a better material.

if you dont detonate and maybe run a block guard, i want to assume you can run a 87mm piston. using a h22 piston would put the piston in the hole about .020 though. just an idea because if this works, then one could run oem domed pistons. decking the block around .018 wouldnt hurt much as i have milled the heads up to .030 to gain compression and used an adjustable timing gear to correct cam timing.

however if the cylinder wall becomes too thin it could lose its press fit and walk around which would lead to a catastrophic failure. this is a potential for a cheap high compression f22 because i know we are pretty cheap

F22 block
-h22 pistons (10:1 compression or more?)
-stock crank and rods
-needs to be bore/hone
-decked

f22 head
-cammed via bisimoto stage 2 or delta 272
-killer valvejob
-surfaced but dont take too much material off

it would also need a custom headgasket huh? cometic can provide that...

if you can source cheap machine work, you can get it built for 1000 bucks.

To do/Progress:
-Bore and hone (need to take out about .083)
-Call Cometic for custom headgasket
-Make Torque plate
-Order oil pan

Cylinder head
-Guides
-Valves
-Valve job
-Delta 262
-Surface

[sulimed]

it's not IF you can get away with it.

it's how long.

[GhostAccord]

I want to try this. the iron sleeve is about 125 thick or 1/8" at 85mm

so ideally, a 87mm piston would make the iron sleeve about .085". the aftermarket dart B20 block with a 84.5mm piston has thier sleeves at .060 granted it might be made out of a better material.

Granted the dart block probably has press fit iron cylinders & not iron sleeves.

The wall thickness of the F22 cylinder is 8.5mm. Only 3.5mm of that is iron. The other 5mm is the aluminum cylinder casing.

Therefore if you go out to 87mm your only leaving yourself with 2.5mm of OEM Honda iron sleeve. (??? iron content).

My Darton M.I.D sleeves have a wall thickness of 6.5mm w/a total cylinder diameter of 97.5mm. Taking them out to 90mm is the max bore Darton recommends for N/A. That still leaves you with 3.75mm of high quality ductile iron.

I look forward to seeing this build come to fruition. So many people ask about boring F22s out to 87mm. Never seen one done and it's about time someone documents it.

[Supergenius]

in related news Jose bought my extra set of 88mm Wisecos and the will be going into a sleeved F block.

[wed3k]

Granted the dart block probably has press fit iron cylinders & not iron sleeves.

The wall thickness of the F22 cylinder is 8.5mm. Only 3.5mm of that is iron. The other 5mm is the aluminum cylinder casing.

Therefore if you go out to 87mm your only leaving yourself with 2.5mm of OEM Honda iron sleeve. (??? iron content).

My Darton M.I.D sleeves have a wall thickness of 6.5mm w/a total cylinder diameter of 97.5mm. Taking them out to 90mm is the max bore Darton recommends for N/A. That still leaves you with 3.75mm of high quality ductile iron.

I look forward to seeing this build come to fruition. So many people ask about boring F22s out to 87mm. Never seen one done and it's about time someone documents it.

how do you know this, if i may ask?

i think 2.5mm is plenty (.098"), like i said the dart sleeve thickness on thier B20 block is far less than .098
http://www.google.com/url?sa=t&sourc...-SQAL2jxruL2sQ

now this build would be ideal for a budget street driven build. most likely not intended for boost or a race car but who knows?

torque plate hone is critical.

[GhostAccord]

how do you know this, if i may ask?

I have both the F22 block and Darton sleeves right in front of me. With a .0001 tolerance vernier caliper in hand. The Darton specs I got from their website. And the composition of a Honda cylinder is rather obvious once the block deck has been cleaned/surfaced.

i think 2.5mm is plenty (.098"), like i said the dart sleeve thickness on thier B20 block is far less than .098
http://www.google.com/url?sa=t&sourc...-SQAL2jxruL2sQ

now this build would be ideal for a budget street driven build. most likely not intended for boost or a race car but who knows?

torque plate hone is critical.

I'm not aware of the cylinder composition of the Dart block. I see in there spec chart that a wall thickness of 1.5mm is what is left after an 84.5mm bore. They could have another 9mm of aluminum wrapped around those sleeves. or they could be of a higher strength iron composition.

Do you have a Dart block to measure the actual cylinder wall thickness. Or the grade of iron that they use for their cylinders?

I would say that 2mm or 2.5mm of OEM iron left for stock sleeves would be touch and go. If you want to run it for a budget street build. I say go for it. I said I would love to see the technical specs on how it performs. See what effects it has on engine coolant temps and such.

[wed3k]

okay, i thought you might of watched the machinist or asked how much did he/she actually bore because these sleeves are actually rippled inside. they arent straight cut. or you may of somehow sonic wall tested it.

the only thing i have is a virgin f22 block which i plan on saving because it only has 28k milage.

i need to find a donor for this project. if i can get this to work well and reliably it may go down as one of the cheapest f22 builds in history considering cheap h22 replacement pistons go on ebay for 75 bucks

[GhostAccord]

i need to find a donor for this project. if i can get this to work well and reliably it may go down as one of the cheapest f22 builds in history considering cheap h22 replacement pistons go on ebay for 75 bucks

If your going to give it a go, you should look into the type S pistons to gain even more compression. They are a bit more expensive but you can get a set of BB6 Type S stock or 0.25mm OS online for approx $280 shipped. I realize that kind of takes away from the whole cheap deal. But it's still cheaper than sleeving and buying aftermarket forged pistons.

[DJ metadelic]

Like wed said, honing with a torque plate is definitely a good idea. I know the company CHS carries them for around $500 or so? can't remember. A friend and his father used one, and it was a big help.

[wed3k]

If your going to give it a go, you should look into the type S pistons to gain even more compression. They are a bit more expensive but you can get a set of BB6 Type S stock or 0.25mm OS online for approx $280 shipped. I realize that kind of takes away from the whole cheap deal. But it's still cheaper than sleeving and buying aftermarket forged pistons.

or get some used ones

i talked a lot with jose and he says that i should run a h22 rotating assembly because of the thrust that a longer stroke creates. i just dont like the idea of destroking plus i have to buy rotating assembly.

i think im the only one with the advantage here because machining will be free
who would spend around 1k to have something on par with a h22?

[immeraufdemhund]

man, when i thought about doing that The machine shop I was going to go to was going to charge $10 per cylinder to bore it to 87mm, and He said that he'd put the pistons on the arms for me for free if i put a sticker on my car... but i never did end up doing that before i got rid of my h22, wasn't sure if i was going to use the whole rotating assembly or just switch the connecting rods... just didn't have enough info, but i think i would have broke your cheap record because it would have been about 200 with the gaskets, and boring, and buying a f22 block. oh well. so it goes

i hope this does work for you because if it does i'm going to get a f22 and bore it out and get it ready for 87mm pistons.

oh and just a thought, if 87mm doesn't work try a f23 piston (i think 86mm??) that might pick it up a little

[wed3k]

86mm is what i have my 12:1 Arias F22 bored out to. so i know for a fact that it is good.

[trah]

just use a h block with a f22 head... Been done I can tell ya if YOU ARE SERIOUS! weeeeeeeee

[wed3k]

but a h block is harder to find than a f22 and more expensive. 200 dollars to get me a bottom end could potentially get me type S pistons.

plus, i have to worry about headgaskets and all that wierd shit. it's all about keeping it simple because a headgasket is the last thing i want to run into when im trying to diagnose.

[PR CB7]

if machine work is free, and you dont want to sleeve, im pretty sure, there's a few members here that would sell a h block for cheap

f22 stroke on an h with an f head will be basically what you'll be doing

95mm stroke on 87mm bore w a 50cc head

hell if your going to be using a 50cc head, you're better off using an h23 head (you dont have to modify oil ports)

but its going to get expensive, also you want to keep in mind longevity, saving money is out of the question when a motor doesnt see even 4k miles