Well, unless you've got a 928 or Cayenne.
If you want to put a V-8 into a 914, 912, or 911.... This would probably be a sweet deal.
http://www.h1v8.com/page/page/1562068.htm
engine weighs 200 pounds, 2.8L V-8, 400hp, mates to a 6speed sequential transmission, 10,000 rpm.
based on the Hayabusa engine.
SPECIFICATIONS:
75 degree odd fire V8
2.8 LITER, 170 cu. in. displacement
84mm Bore X 63mm Stroke
4 cams, 32 valves via internal silent chain
530mm wide x 485mm long x 530mm high
400HP @ 10,000 rpm with stock street cams
245 ft-lbs torque @ 7500 rpm
200 lbs engine weight
Billet nitrided steel 180 degree crank
4340 Carrillo H-beam rods
Billet 6061-T6 aluminum crankcase
Dry sump oil system with 4 stage pump
7.25" or 5.5" Twin disc clutch
DTA S80 full sequential ECU
Unique cylinder offset and cam drive arrangement yields a compact design- Patented