400hp on a 5.3? On motor, not the wheels

[SpecV44]

my 5.3/4l60e swap is nearing completion, and I happen to have a 5.3 sitting in my shed that is complete, along with an LS1. between these 2 motors, which is going to be cheaper to make 400hp and be strong enough to tow with? My truck is nothing more than a towing vehicle, but I want it to be able to tow anything I throw at it. I plan on rebuilding the motor with fresh bearings all around, new rings, and probably all the gaskets. Here is a run down of what it is:

1994 GMC 1500 ext cab long bed
2002 Silverado 5.3/4L60E put into it
stock 2002 intake, intake piping, radiator, aux trans cooler, p/s cooler
It will be getting a set of longtubes as well, in the future.

I am interested to hear about cams, and if I need a stall or not. Chances are that the most it will ever tow is 6000lbs total including the trailer. Obviously in a truck this size, it wont be spinning very high, so I would like to keep the cam to 6000rpm or less, but I want it to make a load of torque down low.

I know the LS1 makes more power initially, so maybe I can swap parts between the LS1 and the 5.3 to get closer to that 400hp mark? I know certain 5.3 heads have smaller combustion chambers, which would bump the compression up a bit.

I have HPT Pro, so the tune is no problem.

[keniff]

swap in a 6.0 with LTs, a NNBS intake, a spec'd cam, PRC stage II heads, CAI
411rwhp

[CHEVROLADE]

ls1 would be closer,but that 5.3 can do it too

[Show&Go]

With both motors there. Id vote for ls1 bottom end and heads. truck intake cause it helps with down low torque. And a good cam. Full bolt ons Being you are looking for at the motor and not the ground... that could be decently close. If not mill the heads down a bit....

[SpecV44]

With both motors there. Id vote for ls1 bottom end and heads. truck intake cause it helps with down low torque. And a good cam. Full bolt ons Being you are looking for at the motor and not the ground... that could be decently close. If not mill the heads down a bit....

LS1 compression is ~9.75:1 correct? How about this combo:

98 LS1
LS1 heads milled, bump compression to 10:1, 10.25:1
NNBS intake
underdrive pulley
longtubes
P&P throttle body
P&P heads while they are off for milling
1.7 rockers
full synthetic fluids (oil, trans, rear end)
some sort of cam (I am not good with choosing cams, I may talk with my machine guy about that)

Unsure if it would be worth it, but what about skipping the NNBS intake and going with a Victor Jr and an elbow? We ran one on the 98 LQ4 Jimmy and had good results.

[skeet]

g

LS1 compression is ~9.75:1 correct? How about this combo:

98 LS1
LS1 heads milled, bump compression to 10:1, 10.25:1
NNBS intake
underdrive pulley
longtubes
P&P throttle body
P&P heads while they are off for milling
1.7 rockers
full synthetic fluids (oil, trans, rear end)
some sort of cam (I am not good with choosing cams, I may talk with my machine guy about that)

Unsure if it would be worth it, but what about skipping the NNBS intake and going with a Victor Jr and an elbow? We ran one on the 98 LQ4 Jimmy and had good results.

save money dont port the throttle body, my pinion its a waste of money, go with the nnbs or tbss 90mm intake and full bolt ons with a TT3000 torque converter and youre good to go

stay away from the vic and elbow it will rip all the tq from the lowend!! specially NA and on a small bore motor . for a cam i would look into a custom grind, talk to some cam specialist

[keniff]

hmmm or a Pro-Flo those are SEXAY AS HELL

[keniff]

you can do a 220/224 113+4 cam to be a good DD plus track toy

[Tank]

you can do a 220/224 113+4 cam to be a good DD plus track toy

... but wanting to keep it under 6K and being a tower i would think more of a 212/218...

[txarkitekt]

Yeah, a 212/218 would be better. If he is going with the LS1/heads/NNBS intake, he can cheat up a little...maybe to a 218/220 .551/.542 113+2 LSA.