First off...they stopped making grand prix's after 2007. 2007 was the last year for Grand Prix's. But there are different routes you can go. You can try to find a 3800 supercharged motor already (L67) from a 2004-2006 (they stopped the GTP after 2006), like off a parts car (one that has been in a wreck). Or you could go the way of a top swap, which is just taking the top half off a L67 and putting it on a bottom of a L36 (3800 non supercharged). More work tho involved with getting the parts like the M90 Blower, your pulleys, your fuel rails, injectors, etc etc). Or there is a SS M90 kit you can do...which is even different yet from a top swap. I do not know exactly how it works, but a buddy did it on his 98 GT. But here is a link for an awesome 3800 shop here in Grand Rapids, MI. https://www.zzperformance.com/grand_prix/products1.php?id=382&catid=109. I know my information isn't the clearest. If you need more...I can help you with a person who is much more experienced and knows a lot more than I do lol. ..:cAm:..
First off the Grand Prix was made in 2008, '08 was the last year. 2nd, Draw backs to using an older engine is that any state that truly runs emissions testing will fail it. Cartuning make a supercharger kit for the non-supercharged 3.8L, check out https://www.pfyc.com for more info. zzperformance.com and intenseperformance.com are great sites that specialize in the 3.8 liter engines.
After 2004, the Series 3 supercharged engine is the L32. The non-supercharged is the L26. There is alot more work to top swapping then just injectors, fuel rails and supercharger... I will post up a link later that shows everything that is needed for a complete top swap
JUST SO YOU KNOW... They stopped the GTP in 2007, and they made a GP in 2008, but it came in only the GXP and base models, and also were only sold to Fleet operations.. You should do your research first..
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