So my block took a crap on me and now i have to go with 85.5 mm pistons in a gsr.. I have a 6265 on it.. But my question is how much could I push it.. I tuner said 550 at max.. What u guys thinks.. Does anybody have experience with big bore on boost? This is not a full race car.. Just weekend driver..

 

85.5mm seems REALLY large... What sleeves?

Im running 84.5mm on Darton sleeves and Im a bit worried about doing 600+

 

its in the tune.

 

tune matters a lot... but if theres almost no area for the headgasket to seal, the best tune in the world wont matter

 

 

Im also running a 84.5mm On Darton sleeves. I tell you these sleeves ARE SO HARD!!! of course i run about 480. but i wouldnt be worried at 600, maybe 700. I swear you cant crack them...

 

Yea.. But i wanted 650ish.. But don't want to crack my sleeves.. They are darton sleeves

 

That I's exactly what I'm thinking.. Thats why I'm was going to stay in the 550 range.. For that reason

 

I'm getting really fed up of hearing this crap. Theres only so much a mechanical a part will take before it lets go. People go on like theres some kind of black magic behind tuning that will save your engine from failing. Well i hate to burst you bubble but there isnt. With tuning its either the car has been tuned correctly by someone that knows what he's doing or it hasnt.

 

well if this is only a weekend driver, why do you need 550 hp? i have lots of suspension and a LSD with 480 and i even break loose.

What kind of darton sleeves do you have? MID's or the inserts?

Last question, what do you mean by "your block took a crap"? drop a valve, broke a ring, maybe rods let loose? because a 84 mm bore is just fine. im sure boring it 60 over will not be worth the trouble lol

 

ummmmm you contradicted yourself when you stated this..."I'm getting really fed up of hearing this crap. Theres only so much a mechanical a part will take before it lets go. People go on like theres some kind of black magic behind tuning that will save your engine from failing. Well i hate to burst you bubble but there isnt." and then you go and say this right after..."With tuning its either the car has been tuned correctly by someone that knows what he's doing or it hasnt."... is the same damn thing that other guy said... go change your tampon!

 

I do distinctly remember that Darton states that 85mm+ should ONLY be used for all-motor applications. I'd say that 85.5 is a SERIOUS gamble when it comes to a boosted 500hp engine.

Do this: measure the thickness of the sleeve inbetween #2 and 3 cylinders and subtract whatever the difference is going to be from your previous bore size(84-85.5=1.5mm). How thick are they now(85.5mm)?

 

Lol no its not. I hear this "its all in the tune" all the time and 9/10 its to with some certain tuner been superior to all the other tuners out there. Meaning he will some how save your engine from blowing up by casting a spell on it which no one else can do. Of course non of them actually have a clue... Sorry i guess i went on like a bitch a bit. Its been a looooong day. Tampon is been sent to your door via first class post with your name on the packet

 

lol you cant take an argument and turn it around to make me laugh haha.. yummy

 

I was just trying to explain what i ment... I got the impression it was like that over there to. Never mind anyway. Enjoy your bloody tampon.

 

you arent going to crack a darton sleeve.....

 

have a nice day

 

its not boooooooooost that will kill your motor. people have made 450 on stock b20 blocks so yes you can do it but the man issue is head gasket failure a gasket the big will have to be custom made it really pointless to go that big cause there isnt a huge power gain. if i were u id just resleve the block again, tunning makes power. jeff even made over 600 hp on a type r stock block 81.5 mm piston