Need to make a decision fast 5.7/6.1/340

on an old school 360 stroker, 408 with a manual trans or lockup converter you will get comparable gas mileage to the hemi. it's not the motor or EFI that gives the 21mpg. it's the lockup converter or OD. the 727 with old type converter is the gas hog. not the engine or the body of the car.

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Cannot and do not agree with this - as Ive run both types of motor thru a 3400 PTC stall , 727 full race trans and 8&3/4 diff.

14mpg vs 21mpg highway over two hundred miles st 70deg - 80 deg F

If I was asked what made the difference, Id say infinitely superior combustion in a better designed alloy head, better breathing through much better designed ports, MAP advance ( my old LA ran a mech advance dist only) , and superior ignition characteristics plus a smaller hyd roller camshaft making more power than a larger flat tappet.

Id be appalled if a modern motor only showed the MPG return of a 50 year old design - race spec or otherwise.