Quick ques, ive been haveing people ask me alot about the difference in horsepower when compression is lowered. this is an interesting subject to get your opinion on cause im also curious as to the power decrease. for example: prelude type s with 11:1 was rebuilt and now has 9:1 or 9.5:1, how much did the horsepower decrease on a stock motor? Right now i have a jdm h22a that was built with endyne fi 9:1 pistons as oposed to the 10.6:1 pistons i removed. ive never really thought about the diff untill now. like i said, im just curious if anyone knows. Thanks.

 

Probably not a whole lot. 10whp at the most

 

well the usdm VTEC's are 10:1 190hp whereas the JDMVT4K's are 10.6:1 200hp

A difference of 10hp with a .6:1 higher compression ratio.

I couldn't guarantee the math on that would be the same with every
motor though