why not jdm itr stuff?

 

CTR is way higher CR.

 

So will higher compression pistons give big gians in power on say my gsr? I keep reading about people with after market pistons with higher compression ratios but no one ever tells how big of a diff. in power they made.

 

When you up the CR its usually to help an already built motor run better. Higher compressions ratio for NA builds, lower for turbo. Thats general. I wouldnt suggest buying high CR pistons without other stuff already done (exaust, intake, cams, etc). And you'll need tuning. Otherwise if you tear the block down, replace them, and put it all back together without changing anything from stock, its gonna be a big waste of money.

 

I'm not stock though I have all of that. Figured pistons could possibly be the next step if they help out a lot.

 

You are gonna need to tear the block down to get at the pistons. Pretty much you're gonna rebuild your engine. While you're in there, might as well upgrade everything (I hate having to take stuff apart multiple times when I could just do all of it at once). I'd suggest saving up for some forged rods and forged head bolts to go along with your forged pistons. And since you'll have it apart might as well replace the valves and vale springs with titanium ones (if you feel you're up for the challange). Basically, if you want to keep it simple dont get high compression pistons without solid rods to back up the power.