304 or 345

[grandslam]

Hi all, new here and looking for some info.
I recently got the bug for a Scout II- to drive hunting, and for my second job (part time- visiting farms in two counties). I know gas mileage won't be great, but I was wondering if the 304 got a little better mpg than the 345. I was planning to leave it stock height and run 31's on it. Will there be any noticeable difference? I'm guessing from what I've read they get around 15 mpg.

Also, I've found a '78 304, auto- needs rear brakes rebuilt, exhaust, gaskets from sitting, tires, and the body is rough (needs body mounts, floor pans, rockers, one door, quarters, area between hood and windshield both sides, all wheel wells have rust-some holes). Engine, tranny, 4wd- all ok. He wants $600. Does that sound about right?

Thanks

[WarlordX]

Yeah that sounds good, 600 is a good price id buy that if it were in my area ha ha but bear in mind its gonna need a lot of body work. If your ok with doing it urself and it not looking incredibly nice, then no problem.

[booboy]

you might consider a 2bbl as opposed to a quad you def get better mileage and little drop in performance at least that s my experience on a daily driver

[lindstromjd]

you might consider a 2bbl as opposed to a quad you def get better mileage and little drop in performance at least that s my experience on a daily driver

Actually, that's backwards. 4bbls get better MPG than 2bbls because the primaries are smaller than the 2bbls (as long as we're talking stock carbs here). Of course, it depends on how you drive it, too. If you're always opening up the secondaries on a 4bbl, you're never going to see better than 9 MPG on a Scout v-8.

[Allan E.]

The 345 has stock 4 barrel manifolds available. Better economy. The primaries on a 4 barrel are just like having a smaller 2 barrel. The IH engines do not need much carb.

For a 2 barrel, 275 cfm is about right for a 304. 300 is about right for a 345. The 4 barrel allows you to get that and still have the higher cfm for when you open it up.

Gearing matters. If you are geared too tall, the 345 might give you better economy. If you are geared lower, the 304 might be better. Part of the equation is how hard the engine has to work. I have run 266, 304, 345, and 392 engines in mediums, and there is a definite correlation between size and economy, but I believe that is because I was running them all at the same rpm, 3000-3500. At the same rpm, size is the primary thing. If you have enough power at lower rpm, your economy improves. If you do not have enough power, you use much more fuel, so the lower rpm does not help you.