Best Compression ratio pistons for SR20 rebuild

[Doofer]

I'm rebuilding my Sr20 engine in the next few weeks and Im not sure which ratio pistons to buy.. It'l have a HKS GTRS turbo if that makes any difference? Also what size gasket should be used? It will be standard size bore, ACL bearings and A.R.P bolts top and bottom.. Blacktop non vvt. Anyone have advice for me?

[Driftma]

I'm rebuilding my Sr20 engine in the next few weeks and Im not sure which ratio pistons to buy.. It'l have a HKS GTRS turbo if that makes any difference? Also what size gasket should be used? It will be standard size bore, ACL bearings and A.R.P bolts top and bottom.. Blacktop non vvt. Anyone have advice for me?

it'd be kinda pointless to go putting new pistons into old bores, i'd be getting it overbored if i were you

[Famous jh]

it'd be kinda pointless to go putting new pistons into old bores, i'd be getting it overbored if i were you

What the Wang said, for the love of god bore it!

Is on of the bores surely not damaged anyway sure didn't a ring landing shit itself or something?

[Doofer]

They were just about to go John. I seen the hair line cracks when I took out the first piston. I literally pressed it with my finger nail and the side of the piston fell apart in me hand.. Insanely lucky not to break before that and destroy the bore.. 5 minutes with a honer and it would be brand new again.. How much of an advantage is there of goin over sized. What extra horse power or torque would be gained by an extra mil or two over sized? Genuine question I'm not bein smart

[trevormcae86]

definetly want a bore , or at very least checked , your engine over 15 years old at very least every engine has wear , i definetly wouldnt order anything till bore is measure properly

[Doofer]

And if I was to bore it how much bigger should I go to keep it safe

[Stonie]

0.5mm oversize, no way would I leave it standard size!

[Doofer]

Ok sound.. So when that's done what ratio's and size gasket should I be lookin at? I presume it's not as straight forward as aiming for the lowest compression possible

[Famous jh]

Ok sound.. So when that's done what ratio's and size gasket should I be lookin at? I presume it's not as straight forward as aiming for the lowest compression possible

As said about anyway, bore it, standard bores will be worn by now.. You'd only end up with an engine breathing heavey and spitting its guts out the breather when ya work it hard and prob use oil too...

And if anything a touch higher compression might be nice..

[Dunnedriftin]

They were just about to go John. I seen the hair line cracks when I took out the first piston. I literally pressed it with my finger nail and the side of the piston fell apart in me hand.. Insanely lucky not to break before that and destroy the bore.. 5 minutes with a honer and it would be brand new again.. How much of an advantage is there of goin over sized. What extra horse power or torque would be gained by an extra mil or two over sized? Genuine question I'm not bein smart

0.5mm oversize, no way would I leave it standard size!

As said about anyway, bore it, standard bores will be worn by now.. You'd only end up with an engine breathing heavey and spitting its guts out the breather when ya work it hard and prob use oil too...

And if anything a touch higher compression might be nice..

Im sure you know.., but incase you dont, the standard bores will be worn oversize already, honing the block with further oversize the bores even more... so then your fooked anyway for STD size pistons, so boring the block is the way forward as you can already see...

honing the block makes the bore increase im sure you already know! Iv seen lads not realise this when there doing it, just honing away, making the bore bigger, thinking its grand sure its perfect now & infact they made a balls of it and then had to bore it oversize....

Then you got lads who dont listen, throw it back together, it runs like a bag of sh!te, burns oil & then is woundering where did the fuck up because they dunno how to use a bore gauge

bigger is better... oversize is the way forward & she be mint