well i was just wondering if anyone is using the 086 head with a turbo setup . ive read that it pushes the compression way up, so im not really sure if its possible. what compression would the pistons have to be to run about 8:5 compression ?
well i guess the .074 is the biggest one right ?
I am interested in this too. I have this head gasket already and all the 2.4 head goodies but I know im not going to get the flow i want out of the 2.4 head.
what will the compression ratio be using the .074 gasket, 086 head, and say 8.5cr pistons at 0.02" over
calculator anybody?
^umm.....no he meant what he said, 0.020" or 20 thousandths over.
0.20" would be 200 thousandths which would not be possible on a LD9.
I got a 90 thou copper one from SCE. That will help a little more than the .074. Higher compression isn't really a bad thing with boost. As long as you keep your higher static in mind when your assembling your setup.
- 97 Z24 Racecar work in progress
- 04 WRX STi
ATR Crew Member
^ How much did that run you and where did you get it from?
bored .020" over, .074 gasket and 086 head what pistons will need to be used to maintain a low compresion like stock or less
I don't recall the price. The machine shop that built my motor got it for me. I would assume straight through SCE.
Are you 96-98 or 99+. Just figuring with a stock head gasket (.050) your going to be either 11.7 or 11.5 with the 086 to get down to stock your going to need to go with a 2 point lower piston. 7.5 or 7.9. Now thats going with just piston. You get a little thicker head gasket and do a little combustion chamber deburring that might get you close to another point of compression. So you will need around a 8.5 piston. I know those are an off the shelf part so that might be your best bet. I don't know how easy some 7.5 pistons will be to come by.
Keep in mind if your running HO cams your going to need a slightly dished piston for valve clearance. That means no sock compression pistons unless they have valve reliefs.
- 97 Z24 Racecar work in progress
- 04 WRX STi
ATR Crew Member
Does anyone make those pistons or would they need to be custom made? What exactly cr pistons do you need to run low compression with the 086 head and .074 headgasket?
Talk to Karo at www.carcustoms.net he deals directly with Weisco and can get anything you need. Tell him what you need and he can get it, valve reliefs, dished, stronger wrist pins, ect.... skys the limit.
