patgizz wrote:
so i've been thinking the last day or two.
my 91 caprice wagon had a 305 TBI v8 and 700r4, 2.73 gear, 215/75/15 tires, and would knock down 26mpg highway in the mountains and 27-28 on flat highway trips.
so - what if i put in a 350 TBI/700r4(both rebuilt), 2.73 gear, same height tires, in something much smaller and weighing 1500# less. would i be too far off in expecting similar highway mpg from the little sonoma? there is no mpg difference between a 305 and 350 90% of the time.
The weight has very, very little to do with highway mileage. You've overcome the momentum of the vehicle's mass and are just fighting friction and wind resistance. So a 1500 pound weight loss will only help mileage in the city. The less aerodynamic body would result in lower mileage on the highway.
MythBusters reference again: their aero experiments on a Taurus resulted in massive efficiency gains at steady speeds despite having added hundreds (or even a thousand, i can't remember) of pounds to the car! They covered it in clay and sculpted it and scooped out golf ball like divots.
Yeah, if you're looking for gains on the highway, it's all about aero.
I would think rubber garden edging or something like that would be useful in closing the gap between the bed and cab. Electric fan setups shouldn't be very costly with a walk through a decent junkyard.
Wondering about ignition tweaks (hotter coil/coils, wider plug gap, etc) to try and wring out a little extra.
With a little truck with such an upright windshield, I wonder if a "bugshield" at the leading edge of the hood might help.
I can not stress enough adjusting the nut behind the wheel, the nut is you. Your eyes must have just glazed over when reading that part of my first post. Cruise at 70 on the highway is your problem, especially anywhere where it is even slightly hilly. Quit using cruise except on the flattest of roads and don't drive above 65. If you swap in a newer engine you can take advantage of OBDII with a scangauge to give you instantaneous mileage.
Going along with the efan you can try an ewater pump
They make thick rubber gaskets for filling the expansion joints in bridges. That would fill the gap between the bed and cab pretty will and lasts FOREVER.
The trick is finding some...
tuna55
UltraDork
3/22/12 1:46 p.m.
pres589 wrote:
Electric fan setups shouldn't be very costly with a walk through a decent junkyard.
If you already have a good thermal clutch fan, don't bother.
I had a half ton, carbed longbed 350 auto non OD Chevy. I got 19 mpg highway with my new thermal clutch can. I swapped to an e fan from something else. I got 19 mpg highway. I drove with no fan. I got 19 mpg highway.
It just doesn't matter.
