Quote: The real point behind this wasn't finding the absolute best mileage. It was to find the best RPM to push 5200+ lbs of car down the road. The aerodynamics of a vending machine will not make the job any easier.
I want to cruise at a low enough rpm to reduce engine noise and save fuel while still having the torque to go up minor inclines at 60 mph. Running too low of an engine speed with a container vessel like this will bog down the engine. At what point will that happen with a mild cam with specs similar to stock stuff?
I'd gear it like my old ram, which turned ~2000 RPM at 75, and I didn't have to downshift going up and down typical highway hills doing 60mph in my 4700 lb truck with only a stock internals 5.2 magnum....
which would be ~3.55's, ~30" tires with your 518....that gives an OD cruise RPM of 1650 at 60 mph, 2050 for 75 mph.
3.73's would increase those RPM numbers by ~100, 3.23's decrease them by about 100-150 rpm....
3.91's with 30" tires still give you a 60mph cruise of 1800, and 75mph of ~2300, and may help getting the mail moving from a stop better....
you could also use a relay or something to trigger lockup/unlock based on your MAP sensor, or use a vaccuum switch to do the same thing, too...
for a heavier street car, I like the combo of a loose/high stall lockup converter and tall gears....the high stall gets the motor up into the meat of the powerband quickly even with the tall gears, adn the tall gears make for a nice freeway cruiser.
what might be fun would be to try adapt an LX A580 and maybe some 2.94's...the 580 has a deeeep first, and a not so tall OD...
1976 Spinnaker White Plymouth Duster, /6 A833OD 1986 Silver/Twilight Blue Chrysler 5th Ave HotRod **SOLD!*** 2011 Toxic Orange Dodge Charger R/T 2017 Grand Cherokee Overland 2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)
