I average 15 mpg with 258. The 4 low kicks butt!! I love the torque. What do you average with the V8? Considering a engine swap. No MOD's installed yet. Just stock. with 1 bbl carter.
- posted
20 years ago
Gas mileage 258 vs. 304?
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- posted
20 years ago
Likely real close to the same.
The 4 and 6 are pretty much the same too. You are pushing a brick through the air so the 4 banger has to work hard and the 6 or V8 can work easier.
I have the 2 bbl carter carb on my 78 engine in my 86 CJ7 and running at
70 or so mph turning 2300 rpm in 4th with 33" tires and 3.31 gears gives me a sweet 19 US mpg pretty consistently using 91 octane 'gasoline'. My spedo is calibrated right on too via my GPS.If I use 5th, my rpm drop to 17-1800 or so and the gas mileage sucks.
If I use any alcohol mixed gas or regular gas, I drop from 350+ miles per tank down to less than 250 miles.
My only mod is an Accel SuperCoil with the engine manually tuned and a ported vacuum advance. No computer. The 2 bbl carter and intake as well, but stock with a stock exhaust manifold. I also just have a straight pipe and a high flow muffler on it. CJ's don't need catalytic converters here in Canada for emissions, they are 'utility' vehicles.
She will bury the spedo in 4th and hit over 50 mph at 4500 rpm in second. Who needs a V8? LOL!
Though I just built a clutch linkage for a Mustang 5.0 4 bbl and Mustang Borg Warner T5 in a friends CJ7 and well... It is insane for power....
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT'sPaul Brogren wrote: