What supporting mods do i need so i can put a 3.4" pulley on a Grand Prix GTP?

(2010-05-30 12:18:02) 1. SMG Says: What's the stock pulley size? If it's a 3.5" probably very little. It would be nice to upgrade injectors and the mapping (not to mention the header(s)/downpipe) but not really necessary unless it's an aggressive drop. Keep in mind you'll run a bit lean on this setup and should monitor it (injector efficiency and a/f ratio) and not go any lower without upgrading your injectors. Tag: What supporting mods do i need so i can put a 3.4" pulley on a Grand Prix GTP?