I figured since this is the racing board that maybe some members have put a scat 3.75 stroker crank into their 350 engine. My question related to the gas mileage that you get from putting a bigger crank in. Does the Mileage really go down alot. I heard in the past that a 350 bored .030 got 15 mpg then with the bigger crank to make it a 383 it only got 9 mpg. Is this true? thanks!

 

If you changed nothing but the stroke of an engine you would increase the fuel required for operation to feed the extra cubic inches. The crank alone would not drop it by 6 mpg though.

 

Everything is all relative. The engine may be sucking in more fuel, but it's also putting out more power, which means less opened throttle blades at PT cruising, which can translate to increased gas mileage. Don't always expect drops, and don't always expect gains.

 

Fuel Economy, Engine Efficiency & Power

http://www.viragotech.com/fixit/Fuel...encyPower.html