I'd go with the 2.4L V8 found in the Caterham RST-V8 Levante. I love small displacement V8's. Simon, I think the engine you posted may be a close cousin of this one. By the way it comes in at 200lbs. as well and that's including the supercharger.

Engine 2.4-litre, 40-valve RST-V8 supercharged
Max Power 500+ bhp @ 10,000rpm
Max Torque 300lbsft @ 8500rpm
Supercharge boost 0.8 psi