Originally posted by POWER2BURN
If you have gone from a 350 to a 454 big block.

Was there a big difference in gas mileage?

Could the Big block go 80% as far on the same tank of fuel?
I had a 72 Chevy 3/4 Ton truck that got 10 miles to the gal. made little or no difference if you drove with the wind, - against the wind - empty or loaded.
I'll bet there are 454's out there that would do as good or better.