i was just wondering if a 3.8 supercharger will hook up to these 4.2's? Because these things are all over Ebay. cheap. Just a question, thanks in advance guys and gals

 

If the Supercharger you are talking about is by Eaton, Yes they do work with the 4.2L engine. HOWEVER, the supercharger unit (S/C) is the least of the problem. You still have to fabricate an adapter to mount the S/C to the lower intake manifold. Then there is the intercooling situation because the air gets heated (a byproduct of supercharging) to somewhere around 425 degrees. Then you need some type of management system so the motor knows what to do with the increased amount of air. Then you will probably need to get beefed-up fuel injectors to be able to provide more fuel at boost. Pulley alignment and a new belt also come into play. I'm sure I've missed a few other requirements but I'm pretty much brain dead after a 14-hour shift.
There are a few people who post here that are attempting to come up with a workable solution for just this situation (me being one of them). Take a look at the Supercharging forum for some more info. Have an Outstanding Day!

 

BTW - How is the MAC intake working for you? I've been thinking about getting one - Best price on the 'Net.