i have to replace the piston rings and valve seats, so i'm gonna go ahead and replace the pistons to bump up the compression ratio. 11.3:1 would be had using USDM B16 pistons, whereas i could spend more money and get 10.8:1 with USDM B18C5 pistons. question is, is 11.3:1 too high to run daily? i know the timing will have to be turned back to stock, plus i already run 93 octane anyway. any downsides to this? any input would be appreciated.

 

 

from what i understand, increasing CR's means that the likelyhood of engine damage by detonation is increased.

this likelyhood for damage is then reduced by the use of correct tuning and timing adjustments.

i would suggest that anything under 12:1 is fine for a daily driven car, as long as the fuel is OK and the tuning is kept upto date...

others here know HEAPS more than i do about this so maybe someone else could help...

t..

 

yea keep it below 12:1... but again, it all depends on how strong your bottom end is built... if you go with 12:1 CR, personally, i would go with new valve springs, and maybe bigger injectors.. are you building it for turbo? if so, you'd want a custom ECU program for fuel mapping purposes..