Interesting thread topic................the 360 has a longer stroke and shorter rod.............383 has longer rod, shorter stroke. Lets overlook the 23 more cubes to the 383 for moment...........

typically that 383 will get you better efficiency/mpg at a slightly higher rpm. The 360 will give you more torque off idle/low rpm with the longer stroke and more agressive rod/stroke ratio...............

where is this going???? With the 2.94 gearing and LOTS of mileage..........I'd be looking to do the 360 UNLESS it's all interstate travel.

I, personally, wouldn't want to feed a thirsty V8 on a high mileage daily basis. If I had to, I'd build it for max mpg and big torque down low where it's going to spend all of its time.

I put LOTS of hours into porting a set of 516's for a .060 over 383 in my 69 RR. Did the MP porting templates. Went 1.74 exhaust valve too. Just gasket matching, opening up the bowls, working the valve guide boss can all run into lots of hours. And I think with a mild cam it would raise the efficiency of the motor such that it isn't a detriment to mpg. My RR got 14 mpg hwy to Indy from MI with a 750 AFB, single-plane, 484MP cam and 3.91 gears. Not a gasmizer deal at all but it did like to run at 3000-3400. I gained 2-3 mph thru the traps too!