ok i have a 63 c-10 with a sbc 400 and a 3 speed trans this is a swb truck and im just wondering if anyone has a good set up for 18+ nmpg set up that would work for my truck or just any ideas to make it more fuel efficient
I think it’s going to be near impossible to get 18 MPG or better out of a setup like this. My memory is real fuzzy on this but I think these trucks had rear axle ratios in the high 3s (3:70s-3:90s). Combined with a 3 speed the RPMs are going to be up there.
Your best options are to change the rear axle ratio to something like 3:08s and consider using a 700R4 automatic transmission (assuming you have a 3-speed auto now).
If the engine has a Quadrajet carb these can be tweaked a bit along with bumping the ignition timing up a few degrees.
I’ve owned a number of small block Chevys over the years (283s-350s) and managed to get 20-21 MPG highway out of all of them; although one old Monte Carlo was cantankerous and fought me tooth and nail all the way before getting it where I wanted it.
well its got a 3 spd manual and i was planning to put a 283 sbc in it that has just been rebuilt that has double hump heads and the 350 hp 327 cam. It has a l-79 67 intake also with a 600 edelbrock and the truck has headers and im gonna run a 2.5in exhaust. Im not sure of the rear end gear yet
i got a few of the 63-72 chevy trucks so i should be able to find a lower gear if it has a high gear
and the truck has a 32in tall tire for now
High performance parts like the Duntov cam are not conducive to getting good mileage.
I get about that on the highway with my ‘76 C10 with the 250 engine and the 3-speed, but that’s mostly because the third gear is so freakin’ low it doesn’t like to go much over 55.
I agree with Caddyman.
Please be clear on your goal. Is it power or good mileage?
well he 327 cam is only a 447 447 lift cam so its not as big as you think and its in a 283 otherwise it just has flat top pistons and 64 cc heads
but im thinking about the holley pro-jection for the truck to get a lil more out of it
ive even talked to a few people about turbocharging it so that that would help that little 283 and get a lil better fuel miliage