AO Platinum Member
Join Date: Feb 2002
Location: The land that Time forgot
The thing with racing camshafts is that they alter the valve timing, typically increasing the overlap and extending the inlet valve duration (so the valves open more aggressively and for longer).
That's good for power but then you ask yourself why Mr Romeo didn't do that in the first place?
The answer is that aggressive valve timing affects the bottom to mid-range pickup as a nice leisurely valve timing scheme is best for fuel/air with a low velocity (at low revs).
So, a "hot" cam will invariably increase your fuel consumption as you will lose efficiency at low revs and your car will be less tractable as a result.
At the same time, the cam profile is usually steeper to open the valves more quickly and this causes more pressure on the followers, so you will get more valvegear wear.
Go for a mild cam if you're tempted and use a good oil but avoid being tempted into a crazy cam - the downside isn't worth it.
No bullets for Chaingun..