[Streetwize]

I have a 427 Windsor at 10:1 with with ported Trick flows that flow 252 @.400 and just over 280 @.500. with a .68 o/d tremec and 3.50 gears and 305/50-R15 tires it turns about 1800 @ 65mph but still has PLENTY of roll-on torque. I'm getting right at 21 mpg on the highway in od but if I run it like a 4 speed 1:1 4th it would drop to maybe 14.

Picking the right cam makes all the difference in the world, if you got great heads on the motor you don't need too big a cam and still make great power and very broad torque, an overcammed or under-compressed motor can pull a light Cobra below 2000 RPM but it's not always in a good efficiency zone for part throttle MPG efficiency. Intake port cross section and vacuum make a huge difference too.