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View Full Version : 27 mpg (imp) and that's fine by me!



junior
09-28-2014, 09:06 PM
Never stopped to calculate mileage on my Stude before, but today put over 100 miles on it and it returned 27 mpg imperial which I reckon is just south of 23 mpg US. I'm ok with that, never figured it would get anything close to that...usually it sucks (gas that is), but today most of the driving was steady-state 72 to 75 mph with the engine loafing along at 2200 to 2300 rpm. Drove with economy in mind today so my right foot never found the floorboard once. Pretty strong headwinds for about half the driving, likewise pretty strong tailwinds for the other half of the drive so I figure wind really didn't matter all that much. oh, no Stude powerplant either, but mild 40 thou. over 283 chevy with 4bbl, dual exhaust, and factory lame-ass 305 cam. What gets me is this mileage is just under my weak-kneed chevy Colorado with 4cylinder/5spd. combo that routinely get 28 mpg at those speeds. cheers, junior

Jim B PEI
09-28-2014, 09:19 PM
I got 30 mpg (imp) so nearly 25?? US driving my 57 185 automatic (!!) 4 door from Toronto to PEI a few years back. Not fast, but competent at 100 kph/60 mph+. If it had been a 55 185 with a DG-200 lockup, or a 3 with O/D I'd have been less amazed

70Avanti2
09-28-2014, 09:23 PM
That's really very good gas mileage. Most full size chevys of the 80s / 90s with overdrive trans got 25 mpg us.

JoeHall
09-28-2014, 10:48 PM
Good MPG makes us more likely to drive our Studes.

My bro-in-law gets around 11 MPG in his 46 Stude pickup, with SBC350, TH350, and 2.79 rear gears. He says something has got to change, and has been playing with the Edlebrock that came on it. I am sure he will dial it in eventually. Problem is, he does not know what the motor was built with, i.e. cam, heads, etc.. He' figure it out though.

Congrats on yours Junior. A person can live with that kinda MPG, huh?

Joe

junior
09-29-2014, 10:52 AM
Good MPG makes us more likely to drive our Studes.

My bro-in-law gets around 11 MPG in his 46 Stude pickup, with SBC350, TH350, and 2.79 rear gears. He says something has got to change, and has been playing with the Edlebrock that came on it. I am sure he will dial it in eventually. Problem is, he does not know what the motor was built with, i.e. cam, heads, etc.. He' figure it out though.

Congrats on yours Junior. A person can live with that kinda MPG, huh?

Joe

Joe, on this forum you must be the guy that drives their Studes the furthest and has the best idea of real-world fuel economy with your GT's...please refresh my memory with the mpg you regularly see. thx, junior.

tbredehoft
09-29-2014, 11:50 AM
I get an honest 17 mpg (US) with my '55 land Cruiser with a 289 and 250M transmission. That makes it cost abut $1 (US) per four miles. Makes it hard to rationalize a trip into town for a loaf of bread, round trip is 20 miles. A lot better mileage would mean a lot more driving.

JoeHall
09-30-2014, 11:06 PM
Joe, on this forum you must be the guy that drives their Studes the furthest and has the best idea of real-world fuel economy with your GT's...please refresh my memory with the mpg you regularly see. thx, junior.
I get around 17 MPG on the two GTs, with town & country driving; on the interstate ate around 70 MPH, they both get around 20-21. The 56J gets around 15 MPG with town & country, and 19-20 on the interstate at 70. With a fresh rebuild, the 56J gets a little better, but currently has around 95,000 on the bottom end.

Buzzard
10-01-2014, 02:12 AM
We drove our '83 Avanti 305 to a few meets on several long trips this summer. We averaged about 25 MPG (Imperial). As stated the 305 is lame ass.
Just got back from a 1700 mile trip on rural two lane back roads in Washington & Oregon in our Dodge Magnum SRT 8, 6.1L 467 HP. As long as I could purchase premium with NO ethanol we returned 21+ mpg (US) which equates to about 25 mpg Imperial. With ethanol, mileage plummeted to about 18 US. We weren't holding back anyone averaging 75+ mph and no one passed us.
It seems that ethanol is the real killer of mileage.

Studeous
10-01-2014, 07:40 AM
What carb are you running Junior? Does it have any modifications? What ignition?
Thanks

junior
10-01-2014, 10:06 AM
What carb are you running Junior? Does it have any modifications? What ignition?
Thanks

Brand new Edelbrock 500cfm with manual choke...good old ancient GM HEI. The new carb is stock out of the box, no re-jetting at all. The reason I checked the mileage was because I was getting the feeling a tank of gas was lasting a lot longer than the old AFB I pulled off of it, and the off-idle throttle response was big-time improved. The old AFB was a GM application and about 625 cfm. The only negative thing about the new carb is it does'nt feel like the engine pulls as hard to 6000rpm at full throttle, but that's just a gut feeling and when its all said and done it really doesn't matter that much because the cam starts laying down at 5500rpm and the old glory days of whipping this poor engine are just about over for me (and the engine too)...mostly just a cruiser now. A few years back with more of a cam and the 4.56 gears the car was not so fun on the highway and the mileage was so bad it was'nt worth measuring. cheers, junior

52-fan
10-01-2014, 12:04 PM
On the way to Branson, the 259 in my 52 got 22 MPG and a bit above 20 on the return trip. This is with a 3:42 rear gear and the overdrive not working. I was surprised and pleased. I hope the overdrive may add a little, but on that particular trip there was a lot of hill climbing where the overdrive would not have been engaged anyway.

plwindish
10-01-2014, 01:29 PM
This past weekend, I drove to the Upper Mississippi Valley Zone in Menomonie WI. I traveled with another Blackhawk SDC member driving a 64 Cruiser, who's only request was to keep the Avanti under 70. I complied and ran about 67 mph, giving me a 27.3 mpg (US)on the 325 mile trip up to Menomonie with my 76 400 and 200R4 combination. We ran faster coming back with him leading and "misting" me with his poor rear seal, but I averaged over 23.5 (US) for the entire weekend.

The oil mist should have helped with the air flow right?