Has nothing to do with the engine heat.

I believe rear engine cars are more expensive to manufacture. Nissan, ingeniously, put the transaxle in the rare of the car for the AWD, distributing the cars hefty weight. The electronics driving the setup, turbo V6, AWD stability control, etc., is also ingenious, robust and reliable.

When the GT-R was first offered in the US, 2009, it cost $70K. Today the cost is over $100K. A 2009 GT-R in good condition can fetch $60 to $65K. What other car do you know of that can be driven for 4-5 years and be sold for almost the same price as you paid for it. Nissan keeps raising the price because they know they can get it.

 

Just opinion: I think they wanted to continue the Z-car front-engine tradition, and also keep 4-seat practicality. The rear seats in the GT-R are actually usable for (moderate-sized) adults - mid-engine means no room for passengers, rear-engine means huge levels of development just to make it drivable (cf. 911).

I've always felt that Nissan was trying to send the message, "A supercar doesn't have to be a stupidly expensive impractical toy, it can be your everyday car". I'm not sure they quite succeeded, due to the ride issues, but it's still a good car.