Thanks guy's, that's good info to keep on hand.

As far as the car set up, Tech, this is what I've got going: the cam is not stock from my understanding (the guy before me installed it and it sounds and feels heavy), it has a 3.91 rearend, Edelbrock performer rpm intake and 750 cfm carb. As for the heads and valves, I have no idea. The trans is a 727 torqueflite and engine is a 440.

I have been shifting @ 5,200 rpm's, does that sound right? Another thing I notice is my rpm's at about 45 mph is around 2,500 cruising.

Also, the valve body I have been looking at is a Turbo Action "pro street" valve body which allows you to cruise in "D" but get better responsive manual shifts if/when needed.