Are you swapping big inch to little inch?

rumblefish360 said
As said in the OE post, a lot of stroker combos of rod which I can’t think of a singular stroker with a small cam and tall gear being built here yet.

“Oh yea guys! I have a 408 that gets 22 mpg with that factory dual plane and TQ! The real secret is the Isky “Mile-O-more” cam I have in there. What a broomstick!
I can’t wait to try the OD trans and 2.45 gears with my 3.15X15’s!!!!!
:rofl:

What’s decent mileage from a stock ‘70-440?

I might actually do that. Good heads, probably a dual plane (Performer RPM or M1) intake, mild roller cam, TQ carb...2.94 or 2.76 gears and OD. Might top 25mpg highway in a Duster. Friend did it...has a 408 stroker with I think the old MP aluminum Magnum heads, in an Aspen wagon with a low gear 999 and 2.76 gears. Done by just past 5000rpm...but pulls from 1500 and will top 20mpg on a road trip.

And looks like a 318 down to the vacuum lines and Lean Burn box. :steering:

Professor Fate said
Reminds me of an old saying from my days in engineering school (something like):
"It's more efficient to run a larger engine at low loads than a smaller engine at high loads". Within reason.

Spot on. That's how GM F bodies got such good MPG ratings in the 90s. That's how my 470hp, 4700lb Challenger managed 24mpg on a road trip despite 70mph speed limits.