Fuel Mileage question??????
 

I have a 1970 chevy k20, with 4:11 gears, 350 bored 40 over with 650cfm edelbrock carb and intake and mild rv cam, I have a 700r4 that i want to drop in my pickup. What kind of mileage would i be looking at.

Re: Fuel Mileage question??????
 

Crappy. Lucky to get 10 out of that combo.

Re: Fuel Mileage question??????
 

I dont see were you get that i get 10 now with my 350 trans and thats with out overdrive, and the 700r4 has overdrive...

Re: Fuel Mileage question??????
 

what size tires do you have now and will they be the same with 700R4?

Re: Fuel Mileage question??????
 

There are so many factors that influence fuel mileage, it's impossible to say what you will get. As asked above, what tires are you running? If you get 10 mpg now, you might pick up another 1, maybe 2 at best, but that's about it. The best I ever got with my K20 (350, 4.10s) on a long trip was 11.5 mpg, and that's back when I was still running the stock skinny hard 7.50-16s.

Re: Fuel Mileage question??????
 

I have 33 eldarados, not really bigger than stock, just have an aggressive tread.

Re: Fuel Mileage question??????
 

33s are somewhat taller and certainly wider than stock tires, and that hurts fuel mileage. Wider tires often run lower air pressure which also hurts. Something like a 235/85-16 is probably about the right height (depending on your OEM tire size) and skinnier, and can run higher pressure -- which helps increase fuel mileage.

Re: Fuel Mileage question??????
 

I would get you the exact tire size but the pickup is in the shop at the other house, heres a picture when i was rebuilding the frame.

Re: Fuel Mileage question??????
 

Real world you will pickup 1 to 5 mpg probably with it.