IDK, Both the Green and The GT30 make over 400WHP on pump gas, which is pretty much what you are limited to on a daily Basis. Race gas the Green has made High 10 second passes along with a 20G. The GT30R may be a better turbo, but you make it sound like it will Beat the Green like it is a T-25 or soemthing smaller. Be careful, you'll reach the End of your Rods before the end of your turbo. Why not build a 2.2 Block? That would be nice.
Nice car. How is the spoolup on that turbo? What manifold do you use?