Jalopnik listed the craziest five engines you can purchase today.
Mercedes-Benz AMG 6.2L V-8 (C63 only)
451 hp @ 6800 rpm
443 lb-ft @ 5000 rpm
Cadillac 6.2L “LSA” V-8 (CTS-V)
556 hp @ 6100 rpm
551 lb-ft @ 3800 rpm
Porsche 3.8L H-6 (911 GT3 only)
435 hp @ 7600 rpm
317 lb-ft at 6250 rpm
Ferrari 4.3L V-8 (F430 Scuderia/Scuderia Spider 16M)
503 hp @ 8500 rpm
347 @ 5250 rpm
Lexus 4.8L V-10 (LFA)
553 hp @ 8700 rpm
354 lb-ft @ 6800 rpm
I would make the list a little longer and add the VR38DETT and the LS9.