gearheads and monkeywrenches

beautifullyengineered:

BMW S63 sans block/head castings

BMW say the S63Tu in the new M5 is rated at 560hp. However, it is probably much closer to 600hp.

Why?

The non-Tu (technical update) S63 in the X5M and X6M is rated at 555hp, and runs 17psi of boost and a 9.3:1 compression ratio. The S63Tu motor runs 22psi of boost and a 10:1 compression ratio, employs a Valvetronic system instead of throttle bodies, and has much larger intercoolers.

A 5hp gain for 5psi more boost, almost a point of compression, less intake restriction and cooler intake temperatures? I think not. Try 50+hp.

-B.E.

(via that911)