Just my $0.02, but I think adding turbochargers to the Evora engine package would be a big mistake. Having owned a Noble for 5 years (from new) I can say that 95% of the issues with that car are directly related to poor engine/exhaust heat management, and that in turn is a result of the packaging of the drivetrain.
It's clear that the Evora's drivetrain is very tightly packaged into the chassis in order to optimize size and weight distribution, and, IMO, adding turbos to that package (which was never designed for them) will create enormous heat management issues that will not be solvable without significant R&D effort and cost. DON'T DO IT!
+1 I agree.
I think the best F.I. option for the Evora is a Rotrex SC with an intercooler (preferably air-to-water with a front mount heat exchanger).
- Turbos store a tremendous amount of heat energy, as you discussed.
- The 3.5L is torquey enough that a roots SC is not really needed.
- Rotrex adds power nice and linear increasing toward the top end.
- Power delivery is smooth and predictable
- Less heat, self contained lubrication, and quiet operation (just makes the motor sound meaner).
- The packaging allows for easy engineering even in tight configurations.
- Easy to run an intercooler for more power and safer states of tune.
I had a Rotrex on the 1zzfe (1.8L) in my Spyder prior to installing the 2GRFE 3.5L. It was great! I only sold the setup to fund my 2GRFE swap, otherwise I would still have it. I don't plan on ever adding boost to the 2GRFE in my Spyder, but if I did I would definitely use a Rotrex again.
Here is a dyno for my old 1zzfe Rotrex setup. (note the 1zz originally made around 125rwhp)!! Imagine what a bigger one would do for a 2GRFE.