The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - What kind of mpg should I expect after a engine swap?

RaysK20 · 08-03-2010, 01:30 PM

Cant comment on the over drive, but my 73 k20 gets 13 highway with a well worn 350 edelbrock performer intake and carb, stock manifolds and dual exhaust. I am running 235-85-16 tires threw a th350 and 4:56 gears. While the truck is not lifted, I just swapped off the wide 33-12.50 tires to the 235 and my mileage went from 11 highway to 13. I am currently planning on a 350 rebuild similar to above but raising the compression, a comp 260 cam and headers. I expect to be up around 14-15 mpg with a fresh setup.

08-03-2010, 01:30 PM	#5
RaysK20 Registered User Join Date: Jan 2010 Location: Sweet Home, Oregun Posts: 49	Re: What kind of mpg should I expect after a engine swap? Cant comment on the over drive, but my 73 k20 gets 13 highway with a well worn 350 edelbrock performer intake and carb, stock manifolds and dual exhaust. I am running 235-85-16 tires threw a th350 and 4:56 gears. While the truck is not lifted, I just swapped off the wide 33-12.50 tires to the 235 and my mileage went from 11 highway to 13. I am currently planning on a 350 rebuild similar to above but raising the compression, a comp 260 cam and headers. I expect to be up around 14-15 mpg with a fresh setup.