scottyf is quite correct; the issue is one simply of space in the front end of the car. A GT is essentially a 147; a small hatchback. No-one in their right mind would try to ram a traditional 3.2 V6 (rather than a fancy compact footprint VW VR6) in there, it would be madness. Huge packaging problems, drastic heat management issues, compromised suspension design, difficult servicing access..... But who cares, they did it anyway; that's why it's so great.
I worked as a consultant to the automotive industry (aerospace these days) for many years and have driven hundreds of cars, plain to exotic. The GT has one of the worst turning circles I have ever encountered (along with MK 2 Nissan Primeras) but one blip of that throttle and I just don't care, it's a drug!