Just did some mileage testing on my YJ. Its an 87 that I built from the chassis up. I put in a stock 305 Chevy V8 and a SM465(granny low)4 speed tranny, NP231, 4.10 gears, 35's, about 6 inches of lift.
The engine had been sitting for 8 years, maybe started once a year. When I put it on the road a month ago, I burned $60.00 for a couple runs around town.
So, I started picking at the engine. I ran some Seafoam through it, rebuilt the carb, new Distributor cap and rotor, NGK wires, and regular plugs gapped to .045, Quaker State high Mileage 10w30 and half a bottle of Lucas oil stabilizer.
I ran the engine like that for about 1000 kms, and it starts and runs, dare I say, Perfect!
Took it on the highway today, and clocked the mileage twice, and boy was I pleased. On both fill ups, I averaged over 22 MPG, which I think is good for a V8 and 35's!
That was at about 90KM/Hr or 50 Miles/hr, with the engine at 3100 rpms, which is buzzing for a V8. So overall, Im very pleased. Now if I can just get the oil pressure a little higher.....Hmm
How often do you hear someone say their 4X4 is great on gas!!!???