[twobjshelbys]

My comments embedded

Originally Posted by jhv48

■Are assembled with larger operating clearances
Probably so
■Will likely have a rougher idle due to the high performance camshaft design
Absolutely. The lopey sound from the cam was way cool though!
■Will likely make more mechanical noise
Rattle trap at idle. Sounded great at operating speed
■Will likely consume more oil during normal operation
Yep, about a quart every 1000 miles.
■Will generate more heat due to the increased power level
Not a problem with the king sized radiator in the Cobra, but... The heat in the passenger foot box was intolerable.
■May exhibit non-production-like drive characteristics at various speed and load conditions
Yep, but that was because the fuel injection controller was not set up properly. That was purely a Roush issue and their failure to resolve it is why I wouldn't uy another. Nice engine, not so nice support.
■Will likely consume more fuel due to the increased power level
Actually I got pretty good mileage with mine. 13-15 in normal driving and 18-19 on the highway in 5th gear. I think it was one of the pleasant surprises.