Okay, I realize this has probably been covered before, hell I've asked it before just not here... Anyway. I REALLY need to know what the EXACT compression rarion is for Type-S pistons in an otherwise stock H22. I have been told anything from 10.6:1 all the way to 14:1 that guy was an idiot... anyway. Does anyone have the cold hard facts? I don't want to go forged pistons because it cost to much with the need for sleeving but, I am aiming for about 12:1 compression and I need to know how many tricks it'll take to get Type-S pistons there(flat valves, spoon head gasket, decked block, etc...)

Oh yeah, and on a sidenote when I see .02 oversized Type-S pistons for sale are these from Honda or what? I mean did Honda really make a few of them oversized?

 

Compression is 11.0 for Type S piston.

I believe all the Honda pistons are made by some other company. None of them are made by Honda whether it's oversize or not.

 

Really? just .4 points above a JDM H22... Okay well, I might be able to squeeze 12:1 outta that.

 

If you want to be exact I think it's 11.1:1. Search for a trhead I started a while back on calculating CR.