Orangemagic

iTrader: (2)

I am working on gathering all the parts needed to finish my setup. I'm going to be running a gt-88 turbo, 50mm waste gate and 60mm bov all jgs. Its gonna be a front mount custom setup. My plan was to have my 408 finished but its looking like its gonna be a little while till its ready to go. I have a high comp 347 in the car now running eagle rods and diamond pistons "flat top -2cc"
My question is how much will these pistons hold up to with a 317 head with a thicker head gasket? I'm up in the air about changin to a weisco low comp piston. Would it be worth it?
My goal for the 408 was 800+hp. I was hoping for 700 or more with the 347 but don't wanna push the comp/piston limits. I have the fuel system, Turbo, and all misc things taken care of I just need to know what direction to head.

TurboAv

iTrader: (6)

Need more info. Have the 317 heads been milled at all or are they stock combustion chamber size? What is the compressed thickness of the head gasket you want to run? How are the pistons installed in relation to the deck? For example mine are .015 in the hole. Bore and stroke are also needed. Once you have all those numbers plug it into a compression calculator and get your new compression. Using a .050 compressed head gasket, .015 in the hole, and 71.06cc combustion chamber it comes out to 9.26:1. You would be more than good with your current pistons.

http://www.race-cars.net/calculators...alculator.html

Casting Number 317
Head: 2001+ LQ4 6.0 Litre Truck
Material: Aluminimum
Part Number:
12572035
Combustion Chamber Volume: 71.06cc
Compression Ratio: 10:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

black98ws6ta

iTrader: (77)

The off the shelf Diamond pistons are .010 out of the hole. On pump gas you would be close to your limits, you could always run methanol injection, or a better fuel. E85 maybe? If it was my car it would have the -2cc pistons, 317's, a mls gasket, and e85. I guess my decision would also depend on how important it was for my car to make over 650 rwhp and how long it till be untill you can build the motor you want.

Orangemagic

iTrader: (2)

Thanks guys. Just so i everyone is understanding I'm running my 347 not the 408 yet. The compression is 9.5 to 1.