I've searched a fair amount online about this topic, but I wanted to ask the same question here to see if anyone else has run this setup. I have a set of Vitara pistons/rods (https://www.speedfactoryracing.net/p...a-piston-combo) that I was going to use for a turbo build for my 1997 Honda Civic DX (d16y7), but I decided against the turbo.

I'm pretty sure I know the answer to this, but will installing the Vitara pistons/rods, while keeping everything else stock, including the ECU, create a lean condition? I think the answer is yes since the compression ratio will go from 7.6:1 to 8.5:1.

Still, I wanted to ask because I plan on completely rebuilding the d16y7, and I already have the Vitara pistons/rods in my possession. Has anyone ever tried this setup? If so, how did it go?

 

I don't think you'll necessarily be lean, however without being tuned and with the lower CR pistons, you'll actually lose power. Unless you plan on forced induction or nitrous (either option with a proper ECU that is tuned), I'd leave it alone.

 

the compression ratio you are comparing is vitara pistons on stock length rods to vitara piston on extended length speedfactory.

what you should be comparing is your stock 9.4:1 to 8.5:1


there is no benefit to lower the compression ratio below stock if you are not doing any forced induction.

the car is already slow, why make it slower?

 

Thanks so much. I didn't realize that. I thought 7.6:1 was stock. I appreciate your reply.