Max MPG- slant vs 318/340

The conditions of the day effect mileage some no doubt.

I'm surprised some of the slant 6 guys didn't blow more smoke up your *** with some of the ridiculous reports the have me of north of 35mpg's. A few Bafoons report and swear they got 40.

Here is a case of real life & no bull **** with the parts used.

A 3700+lbs.. 1979 Dodge Magnum. 360 cid. Best of 20mpg Hwy.
Parts used on this good running condition mill were;

An OE trap door air cleaner '72 or '73 model year IIRC???
K&N air filter
Carter 625 AFB
OE iron 4bbl. Intake from '79
MSD ignition coupled to a OE vacuum advance distributor
(Not a stock distributor on that year.)
Dual exhaust off the manifolds @ 2-1/4
(Due to the law....)
An H pipe was used with Twin high flow cats into cheap Thrush turbo mufflers
(Quite and no droan, loud enough to raise and eyebrow when you mash the go pedal)
904 trans - stock, deep pan added.
8-1/4 rear with 2.76 gear and 245/60/15's

Things I wished to get but never did get a chance to get and experiment with we're;

Headers
Split duration cam (in a useable power band fitted for the cars set up)
An LD-340 intake manifold
A TQ carb with it's tiny primary side