Gas Mileage

nvrstuk said:

That's the problem I wouldn't mind having but I wouldn't mind a little bit of "attitude" ! I wonder if someone has a recording of a big block him with those super 50s?

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I have often wondered if you were running really high compression would it make the 50's sound meaner.

nvrstuk said:

That's the problem I wouldn't mind having but I wouldn't mind a little bit of "attitude" ! I wonder if someone has a recording of a big block him with those super 50s?

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Well responding to this part is off topic but I'll post mileage as well to keep it in line. I have a 70 series and it is quiet enough cruising around but still has a bit of attitude when you open it up. I think it's about the best of both worlds that you can get.

My mileage which is all town driving, up to 60 mph and I averaged 11 mpg before I adjusted the carb. Still waiting for numbers from those changes but I wouldn't expect too drastic a difference but my idle was really high and my timing a bit late so we'll see.
302, stock cam, shorty headers and a 600 holley, 2.5" lift, 30's, AOD, 4.11 gears.

I learned this, you can't even begin to compare the same exhaust system with two different engines... even with the same block. My stroker has to be at least twice as loud as the 351 was! So if you're listening to the Internet to see what your new exhaust system will sound, like good luck! ; )

Back on mpg topic, if your figure mpg by not driving at least 200 miles your accuracy won't be very good...too many factors to account for when you're only travelling 50 or 100 miles and then doing the math...

I usually factor a whole tank in my mileage figures, but am happy to play with numbers based on 100 miles as well. If I'm only trying to determine "highway" mileage, and not a combined mileage, I don't mind using the lower numbers.
This way your peak mileage reading is still at least a valid number for your setup. If not completely consistent over time.

I've used as little as 65 miles for testing different things. When I had the time to waste (hard to remember a time...) I would literally go out late at night to avoid the traffic slowing and speeding thing, and run the same route using different setups, with mostly using cruise control.
Different speeds, tire pressures, overdrive vs 1:1, oil viscosities and fuel octane ratings. Just to see if they made any differences.
Sometimes they did, sometimes they didn't.

One interesting note was running my '96 K1500 when it was stock, and after the lift and 35" tires. When stock, it would get it's max mileage (17.5) in overdrive at 60. Shifting to Drive would lose a tiny amount. But after the 35's were installed (same 4.11 gears) my mileage went down to 13 and would not change whether in overdrive or just drive. At least between 60 and 70 anyway.
If I remember it was only about a 400-600 rpm change between the two at 65, but that was a long time ago and I don't really remember.

The biggest gain in fuel economy came after re-tuning it with an early version of the Hypertech OBDII tuner. Never got back to original stock mileage, but at least it got 2mpg back to 15.

Paul

Hey Paul I'm sure you've got a good system worked out and you're pretty accurate but the average guy is not pulling up to the same gas pump, at the same station, facing the same direction so the Bronco is leaning the same amount every time so that way you could easily figure you could end up being 10% or more off as there are so many factors influencing mpg, that's why I was suggesting a couple hundred miles... I polled my students several times over the years while doing the in high school teaching gig and the majority don't even know how to figure miles per gallon -- they say just look up at the LED lights on your dash! It's pretty sad LOL

Even have a matched set, pocket protector and propeller head cap!
Filled up at the same station right at the on-ramp to the freeway even. No city driving to spoil with my numbers.

And yeah, we're not talking about EPA regulated numbers to show someone spending 100grand on the new ride. Just something for comparison purposes.
Funny about those old mileage ratings from Ford though. Wow, never would have imagined 20-something from these stock with a V8. And lucky to be even close with one of the sixes too.
No wonder people complained about the discrepancies with their early ratings! For me though, in the modern times (since that '96 Chevy) I've never failed to get more than the rated mpg on the sticker. Not sure what all the hullabaloo was about that made them revise their estimates down again this last year or so, but apparently they get a lot of complaints from people who expected no less.
I bet most of those were not being very careful though.

paul

Hah! Yeah, that's why we often say around here the best theft deterrent devices on a Bronco are the three-on-the-tree, and the manual fuel selector valve on the floor!
Sad, yes. But look at the fancy and safe new cars that kids get to drive these days.

And let's not forget the fancy gadgets that the kids get to play with these days too. That's sad in that these are going to be the quickener of the onset of autonomous driving cars. 'Cause the young'uns just can't stay away from their gadgets long enough to do something as pedestrian as driving a car..%)

Paul

Them 3 on the trees can be cornfusing to that new generation, that's for sure.. lol