Spend your time on reliability upgrades, wrong vehicle for performance improvements. Key pm work:

1. Sunroof leak issues - search my post - prevents headliner issues.
2. Coat CPS cover with aluminum foil to prevent CPS failure.
3. Remove door panels and lubricate window regulators to prevent common failures.
4. Lubricate cargo door handle to prevent rust seizing
5. PCV mod to prevent oil leaks
6. Inline thermostat mod to prevent overheating
7. Replace all original cooling system plastic or rubber components to prevent overheating and head gasket job
8. Lubricate door straps to prevent popping
9. Coat rear frame to prevent rust
10. Remove and coat cowl panel with bedliner spray to prevent UV cracking
11. Wax exterior to prevent clearcoat fading
12. Lube front driveshaft and/or replace u-joint to prevent failure
13. Replace shifter boots - make your own with leather and superglue
14. Check idler bearings for wear and replace if necessary
15. Sand and recoat fender flares with bedliner.

Have fun!


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the cost to rebuild one of these motors you are better off finding an LS (aluminum 5.3) gen3 motor, 6L90 trans (run a trans controller), and a NP pass drop t-case. Weld in motor mounts are cheap, you bump up to a 6 speed auto and the ability to run rwd for normal street driving. Lots of wiring but it can be done to play nice and if investing all the time and money then bumping up to the 6L80 or 6L90 is totally worth the extra gears. Custom drive shafts would be the last piece but those wouldn't cost anymore than upgrading the stock shafts to Tom Woods.


If you couldn't tell the work from home has freed up a lot of my time and I'm getting tired of not being able to cruise up the mountains here and swapping 4.6 internals and a cam I'm not sure are worth the headache for more of the same issues. I'm looking to go with a gen3 6.0 motor as it's simpler and less modifications and the trans controller is pricey to run a 6L90 but I won't have to change gas pedals or worry about the VVT (which my wifes 07 denali has and sucks big time).

 

Nice pick-up! It was just an example. I think there was a company supercharging the p38 4.6 in the late 90's......can't remember the name.....

But one could:
get a set of lower comp pistons
MLS head gasket
H beam rods
Cam matched for supercharging
supercharger or maybe single turbo or twin...
port heads
Haltech control....

mmm...sounds like fun!
Not to sidetrack too much but here are two pics of my last turbo build: