Hrm for the price of that truck I can buy an '01 Z06 and run circles around it...and still have $15K left over to buy an old truck ('69 Cheyenne&#33 and stuff an LS1 into...



An 8.1 only comes in the 2500HD. RCLB is the only way. But the setup is great. The Whipple is too small to feed it past 8psi. I was telling Allen I thought of going with a 6.0 in my 2500HD I am ordering in the spring vs the Duramax. You can stick an ATI F1 headunit on there to feed a 422 to 15psi easily!

BUT a Duramax can get up to ~750rhwp/1400rwtq and still get 20+mpg. No way in hell will a 15psi 422 get more than 12MPG.

Now if you could put an F1 on an 8.1... or if better heads were made for the 8.1