blue t said:Robert why do you always suggest a t6? In this case wouldnt some thing like a 76gts be better suited and much more street friendly. Also as far as gears go I would run 3.08 or 3.23 trust me when I say you wont need any more than this. Plus with the engine you have they will keep the rpm's down if you run 1/4 mile. You can and I would go L/A in the intercooler and you can do this and keep room for a passenger.
T-6 over T-4 P/R.
The smaller say S475 will out perform the larger 76GTS. Part of the performance is from reduced back pressure.
A 360 + cid motor with the gts made little over 600hp at 22psi with nearly 50 psi of back pressure.
A 357 cid motor the an S475 T-6 made 712 hp at 18 psi with 25-28 back pressure.
All the power was not from reduced b/p, some not all, the balance is from a better compressor moving more air and creating less heat. AIT are a killer also. The smaller turbos often have nasty temp issues.
Last is spool. The difference may only be a couple hundred rpm maybe 400. The big T-6 will be making boost by 3k. Do you need to go lower. Most guys don't have enough Con Rod and oil pump to support 7 psi of boost at 2k much less the fuel to run a diesel type speeds. A gas motor need some rpm to keep the parts alive.
You'd never hit a 225 shot of N2O at 2000 rpm! Cylinder pressure and tq would fold the rods.