Intake manifolds

[Jason Schneeweiss]

I have a 99 gmc seirra with the 5.3L and a whipple supercharger. Would changing the intake have any benifits. Like going with the ls6 or so on. Any help would be great. I am running electric fans.

[va2001ss]

I have a 99 gmc seirra with the 5.3L and a whipple supercharger. Would changing the intake have any benifits. Like going with the ls6 or so on. Any help would be great.
The truck intakes are about 3 inches taller to clear the fan, that's why the LS1/LS6 manifolds don't work on the trucks.

[Naf]

You have to understand the purpose of the intake manifold.

You can always convert to an electric fan which will dramtically open your engine bay and release some hps. But changin the manifold will gain in HP and lose in Torque. The long runners on the GM trucks give the 5.3 more low end torque. Short runners will give you more redline Hp.

Its a balance. If you want there are companies that specialize in porting the intake manifold, smoothing it out etc.

[tmarr11]

Better to go with the 6.0ltr intake than the LS6 intake..... IMO. That's what I did with my LS1 conversion into my 1993 Chevy (formerly Throttle Body Injected 5.7 liter). Sure, LS1, LS6, FAST intake are tempting, but not when it comes to torque and a heavy vehicle. Beside, I had an old magazine which showed the 6.0ltr intake actually only ran about 2hp less than the LS6 in that test, but made better torque.