Without overdrive and a tighter centerline camshaft, forget it..I've had my stroker since 2003 with 2.94s and many combos. Gets 14 hwy with a 1:1 fourth gear in an 833. BTW who drives 55? You'd get killed here driving like that...
That's a nice combo and 14 is pretty darn good--I love to get that. The 3.91 gears cost me at the pumps. Strokers don't need as much gearing, 3.23 would be prefect for many towns and 2.94 for 75 mph zones.
Its rpm's and cam, tight centerlines get fewer mpg. The old 340 cam with 114 lbc got 15--16 mph in those cuda's with 3.55 gears. That cam is too small for any stroker engine. Carb tuning is a must.