Trouble selecting Pistons for Comptech Setup (CR)
#11
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Alright, I've decided to go with forged stock compression 11.5:1 pistons and use the Cometic headgasket.
I don't have 3 weeks to wait for custom pistons to be made, and I think 9:1 is too low for my application-- probably better suited to the turbo guys.
I don't have 3 weeks to wait for custom pistons to be made, and I think 9:1 is too low for my application-- probably better suited to the turbo guys.
#13
The factory pistons have inadequate lands for high boost. Slow down and do it right. Sleeve the block, use the 9.5:1 pistons and do it the way you really want it. I noticed very little going from factory 11.0:1 to 9.5:1 other than it starts easier due to less compression.
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Originally Posted by AusS2000,May 2 2008, 08:25 PM
Why would you use aftermarket 11.5:1 pistons when you can use the stock OEM pistons (11.1:1, no sleeving)?
Does that change anything?
I can't find any pistons readily available that aren't either 11.5:1 or 9:1.
This is currently my only car... I mean I "could" go out and buy another car, but I just don't want to right now.
I can't afford another 3 week wait for custom pistons, as I've been without a car for 3 weeks already.
My options are limited to 9:1 with stock headgasket or 11.5:1 with cometic (dropping it to 9.8:1)...
The block is being sleeved either way.
EDIT: I'M AN IDIOT... I didn't realize that 11.5 is not the stock compression ratio... So now, I'm even more confused...
I guess running 11.5:1 pistons with a cometic headgasket is out of the question?
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Originally Posted by Sideways,May 2 2008, 08:31 PM
The factory pistons have inadequate lands for high boost. Slow down and do it right. Sleeve the block, use the 9.5:1 pistons and do it the way you really want it. I noticed very little going from factory 11.0:1 to 9.5:1 other than it starts easier due to less compression.
Do you think that say a JE or CP 9:1 piston is too low for my setup (Maxing out at 12psi)?
Thanks,
Matt
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Matt slow down man.DO NOT buy a 11.5:1 Piston. That is .5 higher than the stock compression, you are going the wrong way man. You need to get a 9.0:1- 9.5:1 . Im sorry your car has been down buy its just part of the game. Do not half ass something because you are stressed on time. If you are still using a 87mm sleeve, and you are short on time, go back to the stock piston and put the car back together. If you want to do it right, go with a Low compression piston. The wait time on some 87mm 9:0 wiseco pistons is not that long.
#18
Go with higher boost..not 12 psi if you can. If you want to do all this work and investment, do it how you want to do it. I just don't think 12 psi, and you want more later can cost you more going with pistons.
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Originally Posted by ERL_S2000,May 3 2008, 12:18 PM
Matt slow down man.DO NOT buy a 11.5:1 Piston. That is .5 higher than the stock compression, you are going the wrong way man. You need to get a 9.0:1- 9.5:1 . Im sorry your car has been down buy its just part of the game. Do not half ass something because you are stressed on time. If you are still using a 87mm sleeve, and you are short on time, go back to the stock piston and put the car back together. If you want to do it right, go with a Low compression piston. The wait time on some 87mm 9:0 wiseco pistons is not that long.
I messed up and ordered the 11.5's without realizing that they aren't stock compression.
I really don't want to run much more than 12psi... My goal is to have a fast daily driveable car.
Thanks for all you guys' help... It is greatly appreciated.
-Matt