What kind of mileage are y'all gettin'?

I just took a little trip Saturday to a model club thing in my 48 Ford. It's running a 53 Merc flattie with a Rochester 2 Jet and a cam and stock 3 speed and rear. I Mapquested the trip to get the miles and figured out that I got just short of 32 mpg at 70 mph! How the hell did that happen????? My Hyundai doesn't do that good! Anyone else doing that well? Robert

 

Holey moley................wish i got that..........i run a Flatty with Isky bumpstick, all the other goodies,and a 39 trans in a 24 track t roadster..........if i get 11 or 12 i am lucky

 

I would guess Mapquest is a little off, and that's how it happened.

 

Although mapquest *could* be a little off on the miles, that just goes to show that the new technology is either not what it should be or not used as it should be. I always got just as good of mileage with old 318 Dodge pickups as most folks do today. It's just a question of setting everything up for maximum efficiency. You can't tell me a Hyundai couldn't be getting 50 mpg.
~ Paul
aka "Tha Driver"

You talkin' dirty or hep?

 

Flatty, big cam, 2 94's, 4:11 rearend, 5speed.
30-35 depending on how heavy my foot gets.

 

I just did a rearend gear swap in the 55, I'm solidly back into single digit mileage now..and the rear tires ain't gonna last long either.

 

Sounds like you need to re-figure your numbers. I doubt that you would get that unless it was down hill all the way!

 

With the single 4 barrel on the '55, I was knocking down almost 9mpg.

We'll have to do a little more testing to see how she does with the tunnel ram!

My 10 second Chevy II could get a little better than 13mpg if I kept my foot out of it.

 

It's easy. MPG is a component of weight of car, wind resistence, and how efficient you have the carb/carbs set up. Adjust the accelerator pump/s back, easy on the gas during accelleration, You can work toward/expect to get 30mpg with any car that weighs less than 2,000 pounds. On my 250, with dual Rochester pot-bellys, cruisin' around 65, I get 28. Arond town, stop and go, I get 21. I had it running leaner than that to start with but had to increase because it tended to run above the thermostat.

 

Another factor is how fast the engine is turning...that's why those big heavy late model GMs can get close to 30 on the highway. overdrive combined with an engine that is set up to run efficiently at low rpm can work wonders.

 

You left out rolling resistance & gearing for efficiency. Skinny tires pumped up tight, & a gear that puts the engine right at the beginning of the power curve will help mileage tremendously. 2,000 lbs.? I would be trying to get 50 or 60 mpg not 30 (if I was building for that purpose).
~ Paul
aka "Tha Driver"

Since I gave up hope I feel much better.

 

hey you got some secret formula....i cant get anywhere near that with mine and it weighs nothing,also running 4:11's maybe the tranny difference i run a 39 tranny..........just sayin...........

 

On the highway, with a slightly heavy foot, it gets 16.6 mpg.

305 w/ 2GC
TH400
3.54 gears
in a 3600 lb car.

 

'Bout 1500 lbs w/me in it, and overdrive. It kicks ass. On the e-way I can cruise at 70+ and turn maybe 1500 rpm. With the new pipes, I created a little more backpressure so I expect a decrease from that.
Anyways, who builds a hot rod for mileage anyways? Thats what small Jap cars built by 8 yr olds are for.

 

well not that i give a shit about the mileage......its the fun that counts.i was just curious..i only got a 10 gallon tank and NO SPEEDO, so its a guessing game at best when to stop for gas{no fuel gauge either} mine weighs about the same as yours

 

[
Anyways, who builds a hot rod for mileage anyways? Thats what small Jap cars built by 8 yr olds are for.[/quote]


AMEN!!!

 

AMEN!!![/quote]

 

That '57 poncho rear with the 5.13 posi is staying in the '55; it won't hurt the mileage at all, right?

 

Ha, the semi annual HAMB "Liar's Club" post has arrived again. Must be spring soon.

 

Gas mileage is a component of efficiency, a result of good design and brain-power, a subject many good mechanics ponder. When asked by an interested party, people are always talking about gas-mileage, I like to talk intelligently about it, instead of blowing them off with some thumb-sucking retort. My pipe sounds more bitchin', runnin' lean.

 

HA-HA The first one didn`t have a chance!

 

Last liar says, "What ever your mileage is, I get better. Oh, and I have more horsepower than you too!"

 

That's another thing..........no power!! Seriously, my Flatty makes maybe 120 hp to the wheels (was 112 with stock heads, new Offys never on dyno).

Just gotta have the tune right for max performance and mileage. With a properly performing engine comes better efficiency.

 

Big pontiac, 472 Caddy, th400, stock Poncho rear, I get 7 on the highway! Dont even want to know what it gets in town!





.

 

If it weren't for the tree-huggers, and EPAs phony agenda, if the focus were on actual efficiency instead of adding equipment that takes more gas to run so they can dilute the exhaust gas flow to obtain phony numbers, oh well, no point in be-laboring................

 

That's the point the nay-sayers are missing, because of ignorance. If you're wasting gas, at cruise, you're losing Horsepower to the wheels. The leaner the burn, the more horsepower, Just short of burning holes in the pistons (of course!).

For standing on it, for maximum horsepower, that's where power enrichment comes into play.

 

283 \ th350 and not sure what the gear ratio is, 15 mpg. the car only weighs 1700lbs.

 

yeah, we can always blame the do-gooders for conspiring to enforce the laws of physics!

no, wait....

 

Squirrel you hit it on the head.
A big factor to getting optimum milage is keeping you engine in the powerband.

My old chebby gets consistant 16-17, city or highway. I don't lug it around town. On the highway I cruise between 2800 and 3000 rpm. Right at the bottom of my torque curve.

A friend and fellow HAMBer has another old chebby, 235 with a 5 speed and a tall gear. Probably not the original carb, but an original type of carb. On the hiway he's turning probably around 1800-2200 RPM. On a good day he gets 12, but he's not spinning into his torque curve,or no running effieciently.

OD, less HP and less cubes also less gas milage. Go figure.

 

My 6000lb car hauler gets 22mpg on the highway with the stone stock 77' 351M someone swapped in. It does have dual exhaust and a recurved distributor. 3.54 gears, 215/85R16 tires, and no overdrive. 140hp rating on this toad of a motor.

Its a slug around town and gets maybe 6 mpg do to having to floor it all the time just to get it moving. On the highway on steady state 65-70mph driving with a 49' chevy on the back - it cruises quite nicely right at its torque peak and gets great gas milage.