I have a 2001 Pontiac grand prix 3.8 but i wonna know can a hemi fit???
You could probably fit a 5.3L LS4 V8, which came in the 2005-2008 Grand Prix GXP.
Anything will fit if you have the time and money to totally rebuild the car from the ground up. But no, a hemi won't bolt in if that's what you're asking. If you want a performance car buy one and them spend your extra time and money modifying it for added performance. GTPs are everywhere and usually they are cheap (supercharged). There are a few GXPs around as mentioned above. "Making" a performance car out or an '01 GP will be an exercise in frustration.
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