I purchased a new N* throttle body from Ryan Hess but you will need an adapter plate to utilize it. Ryan is on this forum. . My associate Brian makes adapters that will enable fitting the generous 75mm N* TB to the series III w. series V supercharger that is on your 3800SC engine. Brian is on vacation for the next week but you can reach him at brianteel@l67swap.com for one of his well made adapter plates. The fit finish and precision of Brians adapters are great.
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87GT 3.4 Turbo- 0-60 5.2 seconds
2006 3800SC Series III swap in progress
Engine Controls, PCM goodies,
re-programming & odd electronics stuff
" I'M ON THE LOOSE WITHOUT THE JUICE "