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What can you reasonably expect for fuel economy?

moparedtn said:
Boy, don't that help a bit! :)

You know, it's funny - back when, we never really were want for an overdrive gear in these critters....
not that I can remember, anyways.
Society now has had entire generations of vehicles that came with O/D transmissions and we're all so
used to them now that these old cars damn near demand one from us now, though.
The automatics are one thing (and to me, boring as hell) but cars I've had like the '89 5.0 Mustang
with the T-5 B/W though - you could enjoy banging gears in that thing (first through fourth were PARTY
GEARS) and then pop it into 5th (O/D) when it was time to chill and cruise. :thumbsup:
Click to expand...
O/D's became the norm after the 70's fuel crisis and the government mandated better mileage from manufacturers. Then in 1988 when the federally mandated 55 mph was done away with and cars were cruising at 80, not 60. That necessitated super high rear gearing or an O/D. My '67 383 TF727 w 2.9? gears turned 2,200 rpm at 60 and 3,000 at 80. Upgrade engine, throw in steeper gears, 3.73, add GV O/D at 0.78 and I'm at 3,100-3,200 rpm at 80.
 
Sounds like "Fred" is running well and getting a decent average mpg. I have a 68 gtx also, she's a 440 auto car that probably gets around 12 mpg. If I had a 4 speed in her like my Coronet I would be down to around 8 mpg simply because I can't help but get on it and grab some gears! Gas cost is just the price of having fun in these old machines, cheap entertainment.
 
I have lots of cars but just a few that I drive on a regular basis. The '91 Ford F-150 sucks gas like a whore. The '97 Camaro does really well with its 6-speed double overdrive. Advertised at 24 mpg highway. The little Pontiac Vibe, really a Toyota Matrix can get 34 combined.
 
33 IMP said:
Good luck finding tires for those wheels, Joe.....
Click to expand...
I am converting to 5 lug so thats a moot point... My sister bought this 83 in 84 and had to put a set of tires on it... I remember her crying.... LOL
The metric sized tire is still made, VERY expensive though...
 
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moparedtn said:
They make a nice transmission and it seems perfectly suited to the little Ford engine.
I constantly heard at the SCCA tracks about mine back in those days that "those T-5's blow up" and
"you'll be swapping burnt up 8.8 ring gears" and "3 races out of that clutch, tops".

Well, I sold the car several years later with over 250,000 miles on it - still with the original drivetrain
in it, never taken apart - and that car got beat like a rented mule every time we took it out.
That's the only non-Mopar I've ever owned in my adult life, too (and I ain't young).
*whispering*That '89 5.0 Mustang stands as the single best car I've ever owned - absolutely bulletproof!* :lol:
Click to expand...
The T5 is designed for less than 300 ftlbs... The TKX is over 600.... Major difference..
 
65 satellite 440 3.55 727TF 24” tall tires 10mpg. I don’t really care about MPG, but for some reason I always figure it in my head. It only took me 20+ years to quit doing it with my work van
 
My 71 340 Cuda with 3.55's and 275-60's on the back would do 17 combined if I was nice to it or 15 if I was a little bit more brisk with it. Wasn't hard to make that figure go down the flusher though by being flat out mean to it. Never checked it after sticking a strip kit into the TQ but it didn't seem to get bad. Wish I'd never sold that car. Dang V6 Dakotas suck gas no matter how I drive them.
 
moparedtn said:
Boy, don't that help a bit! :)

You know, it's funny - back when, we never really were want for an overdrive gear in these critters....
not that I can remember, anyways.
Society now has had entire generations of vehicles that came with O/D transmissions and we're all so
used to them now that these old cars damn near demand one from us now, though.
The automatics are one thing (and to me, boring as hell) but cars I've had like the '89 5.0 Mustang
with the T-5 B/W though - you could enjoy banging gears in that thing (first through fourth were PARTY
GEARS) and then pop it into 5th (O/D) when it was time to chill and cruise. :thumbsup:
Click to expand...
Yes, for some reason overdrive seemed to fade away during the musclecar years. It was a popular item in the 1940s and 1950s. The Borg Warner R10 and R11 first came out on 1934 Chryslers, then got picked up by GM, Ford, Studebaker and others. I think it was last used as an option on 1973 Ford trucks. The R11 was heavier duty but both were similar - a planetary overdrive was attached to the rear of a three speed manual transmission and was engaged with an electric solenoid. By putting the gas pedal to the floor, the overdrive disengaged and you got the effect of an automatic kicking down to passing gear....just like was mentioned in the song "Hot Rod Lincoln".

Usually about a $30 option on a new car, Borg Warner sold four million of these transmissions to car manufacturers.
 
Photon440 said:
Yes, for some reason overdrive seemed to fade away during the musclecar years. It was a popular item in the 1940s and 1950s. The Borg Warner R10 and R11 first came out on 1934 Chryslers, then got picked up by GM, Ford, Studebaker and others. I think it was last used as an option on 1973 Ford trucks. The R11 was heavier duty but both were similar - a planetary overdrive was attached to the rear of a three speed manual transmission and was engaged with an electric solenoid. By putting the gas pedal to the floor, the overdrive disengaged and you got the effect of an automatic kicking down to passing gear....just like was mentioned in the song "Hot Rod Lincoln".

Usually about a $30 option on a new car, Borg Warner sold four million of these transmissions to car manufacturers.
Click to expand...
GM’s TwinTurbo Callaway Corvette came factory with a 400 turbo and a gear vendor overdrive. At the time there wasn't an overdrive automatic transmission that handle that kind of power.
 
Hey-O said:
GM’s TwinTurbo Callaway Corvette came factory with a 400 turbo and a gear vendor overdrive. At the time there wasn't an overdrive automatic transmission that handle that kind of power.
Click to expand...
Perhaps that was why O/D took a bit of a back seat during the muscle car years as well - they couldn't handle
the torque being generated by the behemoths?
(My actual guess is it was more the beginnings of the serious "unit cost of production" whacking that commenced
and got out of hand in the 70's, to the point the QC went totally to **** and the imports gained a foothold as a result).
 
joe smith said:
I am converting to 5 lug so thats a moot point... My sister bought this 83 in 84 and had to put a set or two on it... I remember her crying.... LOL
The metric sized tire are still made, VERY expensive though...
Click to expand...
I just bought later 10 hole mustang wheels in 15s, then later on the 16"pony wheels, both in the four bolt.
 
Don Frelier said:
No that wasn't using the "Imperial gallon" which would be period correct. It was using US gallons.
That Newport was a sweet running 383 a highway cruiser
Click to expand...
My Uncle passed away in 1969. He had a 66 4 dr http 300 with TNT. The next summer my mature cousin brought my Aunt for a visit, from Vancouver Island to Saskatoon. She was a very thrifty schoolteacher, kept track of every expense. She averaged just over 23 mpg Imperial. No I cannot supply proof.
 
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33 IMP said:
I just bought later 10 hole mustang wheels in 15s, then later on the 16"pony wheels, both in the four bolt.
Click to expand...
I found a set of 16 X 7 takeoffs from a 01... I think they are going to look good... $50 for wheels and Tires.... They are buried or I would take a pic...
Single guys can have one of their bedrooms as a parts room..
 
moparedtn said:
Wow, I can't even fathom getting 17mpg out of one of these things. That's pretty darn impressive, given their
construction!
Click to expand...
I think a few key things were going for my car during the trip:
(1) Stock engine
(2) Overdrive
(3) Fuel Injection that could constantly keep the Air/Fuel ratio at 14.7
(5) We drove mostly secondary roads, so our speeds were very often in the 45-55 MPH range. This is a sweet spot (especially with overdrive) where the engine hardly has to work and the RPMs are low. Also, the car's poor aerodynamics don't really come in to play that much at those speeds.

I'll bet if you could measure the fuel we lost out the vent, my MPG was closer to 18 MPG for the overall trip. Yeah, not bad at all for a 70 Road Runner!

joe smith said:
I can't either....
I think a Swede ya meter is needed
Click to expand...
A Swede ya meter??? :popcorn2:
 
moparedtn said:
Obviously, fuel economy isn't any of our cars' strong suits - not what they were
built for, after all.
That said, I actually paid a little bit of attention on today's 100-mile round trip
to the Cruise Against Cancer event in Newport, TN - and the results didn't exactly
surprise or disappoint me?

Reminder - Fred is a '68 GTX with a mild 440 w/purpleshaft, headers, 3" dual (LOUD)
exhaust, 4 speed, 3.55 gears.

What should I have expected for highway cruising on ethanol-free 93?
Click to expand...
509 cuin 590ft PS 4.56 dana 2 fours fat foot I think I get between 3.5 and 4 mpg, fine with me!!! Dave.
 
moparedtn said:
Boy, don't that help a bit! :)

You know, it's funny - back when, we never really were want for an overdrive gear in these critters....
not that I can remember, anyways.
Society now has had entire generations of vehicles that came with O/D transmissions and we're all so
used to them now that these old cars damn near demand one from us now, though.
The automatics are one thing (and to me, boring as hell) but cars I've had like the '89 5.0 Mustang
with the T-5 B/W though - you could enjoy banging gears in that thing (first through fourth were PARTY
GEARS) and then pop it into 5th (O/D) when it was time to chill and cruise. :thumbsup:
Click to expand...
Lots of cars of the 50's had OD's in them. Thought that was a bit odd with the way gas prices were back then but on the other hand, it saves on wear and tear. Both of my 1st gen Dakota pickups are V6's and with 235/75-15's, if you're not doing 80 when hitting a bridge, the will shift out of OD. Both trucks have 3.55's and just don't have the nuts to pull taller tires but they do with a tire that's close to factory tire size of 205/75's and get better mpg but if you go even smaller (I've done that too), the mph and the pep gets better. Imo, the V6 should have come with 3.90 gears at least and would be even better with say 4.30's! Had a 92 Dak with the 5.2 and 3.90 gears that pulled down better numbers when driven brisk with 12mpg being the worse in town when being meaner than hell on it but the V6's will get just as bad or worse when being mean to them.....ask me which one was more fun!!
 
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