400 is doable with the stock 317's a good cam a good tune and good exhaust. Pretty much a cam and assisting bolt ons

 

from reading around the net i thought the lq4's had 300hp stock? how is a cam and tune going to net 100hp? were there other variations of the lq4 power wise? i thought lq4's came in the "HD" trucks and the lq9 that made more hp came in the ss/denali/caddy/tbss?

 

lq4 iron heads: 300hp & 360lbft

lq4 aluminum heads: 325hp & 370lbft

 

a donkey dick cam with good headers and good tune will net 400+ wheels

 

Yeah do the math, a stock engine 6.0 with boltons in a single cab with a stall can break 12s, do you think you could go 12s in a 4200 lb truck with less then 400? cam only 6.0s have gone 12.0 at 110ish.. you will need every bit of 450 to 500 to do that. you do not need a cam to make 400 weather corrected hp in a lq4!

 

The LQ4 only had iron heads for 2 years(99-00)
Only the Lq4 in the Denali was rated at 325 hp, then in 2005 it went to 335.

the LQ4 with aluminum heads in the HD trucks was rated at 300hp up to 2007.

Difference between an LQ4 and LQ9 is about 5 hp if the same tune is used, due to the slight difference in comp ratio.

peace
Hog

 

I have a lq4 with a 226/226 and ls6 heads and full boltons and put down 397 and 446 torque at the wheels so that's another route u could think about taking

 

If you wanna see 400hp on a chassis dyno its gonna take more coin. If 400 flywheel is what your after its cake. To many variables out there to just throw numbers. I prefer to measure my success in E.T.'s...