HELLABRYAN

ok im going to run a high compression turbo setup with a b18a1 with a 82 mm bore with a 11:1 ratio on 10 lbs. with with 82 mm rsmachine itr piston and gsr crank and rods, port and polished head with Crower stage 2 turbo cams 550 injectors we are targeting 310 on 10 lbs.this set up is like boosting a gsr or type R? running 93oct. pump gas. my friend said its never going to last i need some input?? should i trade the pistons for lower compession ones or just keep the ones i have? im not looking for really high boost just around 10 lbs.

Westrock2000

Compression is fine, well more precisely many modern 4 cylinder engines can do that at 10 PSI or less. However it won't be just like a b18c1/5. As your upper RPM efficiency won't be the same (without some work) and since HP is a function of horsepower you may have to use more boost then a VTEC motor for a given power level.

EsotericImage

iTrader: (8)

It will last if you do some homework and find a really good tuner.. Its all in the tune!

I wouldnt get too boost happy either.. 7 would be max i would push on it with that CR, but the tuner would know for sure. I take it your running ARPs in the rods and head. If not, i would look into it.

092eg6

isnt a 82 bore on a ls make the sleeves too thin to boost?

samuraijackass

If your motor is already built you could just get a ticker headgasket to lower the CR. Then you could turn up the boost.

EsotericImage

iTrader: (8)

nope, boost that all day long
tru, i didnt think of that

AlexDphoto

you are right, alot of it is in the tune. however using the term PSI isnt exactly accurate.

If you are replacing the pistons with higher comp ones, why not go forged? It would be pointless to take apart the motor only to replace the internals with stuff that isnt stronger.

AlexDphoto

It would be thinner than some people care to run, but wouldnt make it too thin to boost. However the walls would be weaker than if you had just left it stock bore.

turbociv910

i ran 18 psi on 82mm stock sleeves with a 35r, obviously had piston/rod combo

AlexDphoto

what kind of power did that make??

EsotericImage

iTrader: (8)

im running 10 on stock B20 (84mm) sleeves w/o a problem. NepTune'd