If you put the 3.8 intake manifolds on the truck, you can add the 3.8 super charger kit. Super Six Motorsports has the stroker kits to run you up to a 4.3. They also have in stock the CompCams camshafts that will get you a bit more power. They are made for the 3.8 but the only things that are actually different are the cranks (same block, same bore, different stroke). I believe the heads are the same with the only other difference being the intake manifolds. However, 3.8/4.2 parts aren't cheap. In the long run, and engine swap is almost cheaper.
2002 4.2L XL
*Wanting 2006 5.9 Cummins or LBZ Duramax
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