I just blew the head gaskets and prob warped the heads so its time to upgrade, I saw they make cams for the 01 4.3 which do you recomend?, I want more fuel to the motor I can't find a bigger spider is their one? I will be milling the heads either the originals or another set I figure .010 is safe( I think I have that right).

 

Don't go crazy milling the heads. Coolant leaks from the intake gaskets are common on stock engines. The more you shave off the heads, the worse the intake will fit, (intake to cylinder head angles change when you mill the heads). If the intake doesn't fit properly, the crankshaft bore alignment can be tweeked when you torque the intake bolts down. Here's a warning straight from the GM "dealer issue" shop manual:



The stock fuel delivery system is capable of supplying over a quart of fuel in 30 seconds. You'd need some type of forced induction, (blower or turbocharger) to force feed that much fuel into this engine. There are companies that make bolt on kits for the 4.3 engines... $3500+

The poppet nozzle diameter and PCM pulse width are matched to deliver the correct fuel flow. For example: a 3ms pulse width delivers a given amount of fuel: If you open up the nozzle diameter, the PCM will not be able to accurately control the fuel mixture, without reprogramming it. You're better off buying a PCM performance tuner. The manufacturer would need to know the specs on the new camshaft such as lift, duration, overlap, etc. It's possible to squeeze 500+ HP out of these engines, but it has to be done right, and it's not cheap Seems like at least one of our members has a turbo, can't remember who though.

 

I think I have to mill the heads or find a new set I drrove it at 260 for 5 miles and it got to 260 three times now. Cam wise I'm just looking for a nice bump up.