BrettM
NAXJA Forum User
- Location
- michifornia
So the time will come in the next year to rebuild my '88 4.0 with about 230k miles. I have 33s for the street and 35s for the trail because I notice a significant difference in power and gas mileage. I would like to run the 35s all the time. Oh, and I have 4.88 gears.
Now some would say that "if you want to run 35" tires you better not care about MPG". I understand the reasoning here, but I'm set on 35s, and I'm set on rebuilding the motor, so why not save myself some money on gas (being $2.20 per gallon). I should also mention that even with the tired old 4.0, I've never had much desire for more power, so I have no problem focusing more on MPG than extra HP.
I understand there are MANY things that influence MPG, but I would like to focus here on engine internals.
My thoughts:
I have no problem keeping it to 65 or 70 on the freeway, which puts my RPMs at 2300-2500. A little lower on the gears would probably be nice, but I'm sticking with 4.88s. So would an "RV cam" be a good choice?
Is the stock (242) displacement best, or could I possibly get better freeway mileage with a mild stroker?
what about injectors? those seem obvious as far as MPG. what's the stock injectors rating? would any of the Ford ones (19s?) be a better choice?
Beyond that, I'm not sure what else could benifit me. Throw some ideas at me please! Of course if it's something that will benefit me 1 mpg, but costs $1000 more, I'm not interested.
thanks
brett
Now some would say that "if you want to run 35" tires you better not care about MPG". I understand the reasoning here, but I'm set on 35s, and I'm set on rebuilding the motor, so why not save myself some money on gas (being $2.20 per gallon). I should also mention that even with the tired old 4.0, I've never had much desire for more power, so I have no problem focusing more on MPG than extra HP.
I understand there are MANY things that influence MPG, but I would like to focus here on engine internals.
My thoughts:
I have no problem keeping it to 65 or 70 on the freeway, which puts my RPMs at 2300-2500. A little lower on the gears would probably be nice, but I'm sticking with 4.88s. So would an "RV cam" be a good choice?
Is the stock (242) displacement best, or could I possibly get better freeway mileage with a mild stroker?
what about injectors? those seem obvious as far as MPG. what's the stock injectors rating? would any of the Ford ones (19s?) be a better choice?
Beyond that, I'm not sure what else could benifit me. Throw some ideas at me please! Of course if it's something that will benefit me 1 mpg, but costs $1000 more, I'm not interested.
thanks
brett
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