Gotta say, the 2.3L turbo isn't a bad motor, and decent horsepower can be had with the stock head. 200-250 at the rear wheels isn't all that difficult (a boost controller, and the right ecm and injectors), and if taken care of, the engines are reliable. One 2.3l turbo guy runs sub 10's in a Pinto. Gotta be more than 300 hp at the rear wheels.
The limitation is in bottom end torque. A decent displacement v-8 makes torque at a much lower rpm, which really shows at the strip. The 2.3L, however, is much lighter, giving better handling. I'm not into drag racing as much anymore, but I do appreciate the slot car handling of my SVO, and its all stock suspension.
The 2.3 Turbo is a great engine. The bottom end is indestructable. Just some porting, a few minor mods and crank the boost! 250-300 HP! Well yeah is doesn't have a bunch of torque down low. But drive it like an over cammed small block engine and you will get the idea!
I would go with the V8 in the Porshe. The 2.3 is a popular swap in older RX7s