www.gnttype.org
Spend a couple of days reading through everything...Pretty much everything you need to know is there...Any other questions can usually be answered here...
For the block(casting #25526109), is basically just a standard Buick 3.8L V6 block...86-7 GM G-body cars had them(Mostly Regals, Cutlasses, and Grand Prixs)...It is the internals that make the difference...The turbo motors use a pressure rolled fillet crank(rods and mains)...Stronger pistons(factory are excellent, but discontinued), most run forged...The standard NA rods, heads(with slightly stiffer springs), and block are all basically the same...
I can usually find a good, used, rebuildable 109 block at the local U-Wrench-It yard for about $130 complete...Finding the correct crank is a little tougher...
There are many GN/TRs out there with well over 100,000 miles that are running 11s-12s on original factory unopened motors and minor bolt-ons, some with 100s of passes on the quarter...The key to making these motors live at these power levels is to not have any detonation and have the motor built correctly(don't take this the wrong way, but most builders of Chevy motors are lost with the Buicks, completely different animals, Buicks need tighter tolerances, no more than .002 clearance on the rods and mains...If you build with Chevy clearances, you won't have enough oil pressure and the motor will self-destruct)...
You won't need the Accel DFI to run those numbers or for gas mileage...The factory computer has been deep into the 10s with the proper chip programming...
Most factory stock GN/TRs can get into the 12s with about $500 in mods...All on factory internals and turbo...
If you have any more questions(you will!!!
![Big Grin :D :D](https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f600.png)
), ask away, and people will be happy to help you without any BS answers...