Can you put A NON supercharged 3.8 in A previously supercharged 2002 GrandPrix without A lot of problems?
It's probably not a good idea. Why do you want to make that sort of a swap? You will have to change the fuel pump as well and likely the computer. That could generate problems with the transmission since the GTP uses a heavy duty version. If you're just doing this because your engine has failed, save your time and energy and invest them in your new car. An '02 is not worth that much and there are lots of good ones around for a good price.
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