A Gen 2 to Gen 3 top end swap is a good way to help wake up an engine in a 87-94 MFPI-equipped vehicle. This article is kind of old, but there are still people out there doing it, so might as well post it. It describes what is needed to perform the swap, as well as why it is beneficial.
If you have questions on your own swap, check out the forums for other member experiences, as well as to post your own questions.
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