99 7.4 cam replacement

[BowtieBrody]

Believe me, going from a stock muffler to jones max flow 22" and a single 3" tail pipe made a world of difference. To me it was like driving a truck with the 4.3 and then driving the same truck with a 5.7. Not blow you out of your seat different but I could finally do dually burnouts afterward...

I hope it'll be a difference when I redo my entire exhaust, shorty headers, no cats, full 2 1/2 inch piping through either a Magnaflow or probably my Jones that's currently on the truck and 45'd out the back.
Of course then again it'll have a tuned PCM and a ported throttle body, so it might not be as noticeable...

I know when I cut the stock muffler off my old Suburban, it ran like a ***** ape with close to 247K; recently the old muffler me and my friends rigged on fell off when my brother was driving it to school and he's been driving it around straight piped, and it STILL runs like that with 252K now.

 

[Tom P]

Anything is an improvement over that stock choke factory. They must have figured that out because the mufflers on the GMT800 trucks don't seem to be as restrictive and I don't remember there being much of an improvement when I put an exhaust on mine.

 

[Christian Steffen]

The factory shift points suck big time. The 7.4s definitely have enough torque to keep the rpms down when cruising, and even passing, as long as you get the dumbass tuning out of the way.

 

[Christian Steffen]

One word of caution to head porting, don't go too crazy opening up the intake ports, or you will hurt your low end torque.

 

[Supercharged111]

One word of caution to head porting, don't go too crazy opening up the intake ports, or you will hurt your low end torque.

I don't think that's where the power is anyway. Usually near the valve and in this case those stupid ramps that the small blocks got rid of in the Vortecs.

 

[Christian Steffen]

I don't think that's where the power is anyway. Usually near the valve and in this case those stupid ramps that the small blocks got rid of in the Vortecs.

My heads are currently stock. I've been thinking about pulling them to do some cleaning up in there. If I do, I will be sure to do some before and after runs to compare the power.