Best gear for mileage?

[sbca96]

I am running a 3:31 TT behind my TKO/TR-3550 5 speed. 5th gear is a
.68 OD. I'm able to pull grades in 5th, thats with a stock R1 engine.
Avantis are heavier than Hawks on average. I had a 3.07 originally in
my '60 Hawk, and it went pretty good. With the 3.27 1st gear in the
TKO, the car feels like its got stump pulling rear gears, then put it
into OD on the freeway and its barely turning over. A modern trans is
the only way to go!

Tom

'63 Avanti, zinc plated drilled & slotted 03 Mustang Cobra 13" front disc/98 GT rear brakes, 03 Cobra 17" wheels, GM alt, 97 Z28 leather seats, soon: TKO 5-spd, Ported heads w/SST full flow valves, 'R3' 276 cam, Edelbrock AFB Carb, GM HEI distributor, 8.8mm plug wires

[buddymander]

Thanks for posting Ray. How was your Lark from a dead stop with the 3:07? The difference between the 3:07 and the 3:73 is .66. Isn't that close to the Studebaker overdrive ratio? I figure it should have cruised the same in third before as it does now in third OD. But I'm more interested in how it took off with the 3:07 because I think Hippies car is a little heavier, but with the 289; more powerful. I haven't checked the ratio in my new (old) 57 Silver Hawk (289-2bbl, 3 spd OD), but I'm already wondering what would be the best all around ratio. With what I've heard so far, 3:31 or 3:23 are beginning to sound optimum, but if I come across a 3:07, I think I'll take it. Has anybody else messed around with timing changes while running down the freeway? Using a vacuum gauge and a choke type cable hooked to the dist.? Also using a tach at the same time would be best.

[Hippie]

Found a good buy on a NOS 3.73, 50 RPM difference at 60 MPH over the 3.54's. That's not enough to talk about. I started a new post about pinion splines in case everyone was bored with this one although I must say there has been some "stimulating" discussion. Need to know if the '60 Lark would take the early 10 spline pinion or the later 26 spline. y guess is 10 spline.

Analog man in a digital world.

[PackardV8]

quote:Has anybody else messed around with timing changes while running down the freeway? Using a vacuum gauge and a choke type cable hooked to the dist.? Also using a tach at the same time would be best.

FWIW, that's exactly the technique the Studebaker engineers used in choosing the OEM gear ratios nearly sixty years ago. What has changed since then? Oh, yes, in most of the country, we have lower octane fuel with ethanol, which lowers specific power output. These days, Studes are rarely ever driven with a full load of passengers and luggage, so a bit less gear is OK. Bottom line, if fuel economy is the end-all-be-all, one or two ratio higher than OEM, three steps if you don't care if it is a dog on acceleration.

quote:Found a good buy on a NOS 3.73, 50 RPM difference at 60 MPH over the 3.54's.

What tire size did you use in the calculation? It should be closer to 150 RPM difference.

thnx, jack vines

PackardV8

[pcmenten]

My 86 Mustang GT has a 302 ci engine. With the roller cam it makes very nice low end torque. I'd guess that the torque of the 289's long crank would create similar low-end grunt. So, off-the-line performance ought to be there. My GT has a 5 speed overdrive with a .68 top gear and a 2.73 rear gear ratio. Frankly, even with such a low rear gear, I wish first gear was a little taller. Fuel economy at 65 is above 25 mpg. I've never worked on the clutch. I bought the car with 80,000 and it's at 150,000.

So, if your engine is making decent torque between 1250 and 2000 RPM, I'd use the 3.07.

Best regards,

Paul

[buddymander]

And I would think a Mustang Gt would outweigh a Studebaker Hawk by at least several hundred pounds. I haven't seen any mustangs V8 equipped that were "dogs off the line" in any sense of the word. And with a .68 OD and 2:73 gears...hmm what does that equate as a final drive ratio? I do believe the Studebaker engineers would be all over this with timing and advance curve changes to work better with today's fuels and oils. Not to mention tires with awesome traction (that would do it for that second gear start baloney). That's another thing: Why have a second gear start trans in one car-- and OD with a stump pulling screw in another? Studebaker designed their second gear start cars to be "dogs off the line". I don't agree that they knew what they were doing. I think they were just following a fad. It's like my 69 chevy van had a turbo trans with the 2.5 first gear and a 3:36 rear ratio--just like the 68 van that came with a powerglide with the 1.8 first gear ratio. So I changed it to a 2:73, and it came off the line just as hard. My freeway RPM was cut almost in half. Those engineers can't keep their eye on every aspect. The technological breakthroughs exhibited in the 51 model as far as the front suspension and the V8 were never equaled by Studebaker again. It seems to me that they just kept kicking around the same ol stuff for 15 odd years, til they finally gave up and went chevy. They knew their motor was outdated by 56; that's why they tried out the Packard, but saw the error of their ways after one year and stuck a blower on the 289. I mean they didn't even go for an aluminum water pump housing, or incorporate it into the timing chain cover. And kept the old bellhousing alignment technique. No aluminum bellhousing, silly flywheel bolt arrangement, the same intake/exhaust valve proportions. I think by the late fifties, Studebaker was just trying to sell a bunch of cars. That's why I'm selling my GT and putting my efforts into my 57 Silver Hawk.

[sbca96]

quote:Originally posted by buddymander
The technological breakthroughs exhibited in the 51 model as far as the front suspension and the V8 were never equaled by Studebaker again.

I dunno about that one, standard disc brakes on the Avanti and that
hill holder were pretty cool, not too mention that Twin Traction it
got from Packard. Had Studebaker more money, the Avanti would have
had an independant rear suspension.

Tom

[Hippie]

quote:Originally posted by PackardV8

quote:Found a good buy on a NOS 3.73, 50 RPM difference at 60 MPH over the 3.54's.

What tire size did you use in the calculation? It should be closer to 150 RPM difference.

thnx, jack vines

PackardV8

Effective tire diameter is 26.03 but must have hit a wrong button last night, I'll split the difference with you, came up with 103 RPM this morning after a good nights sleep, checked it 3 times.

Analog man in a digital world.

[Hippie]

quote:Originally posted by StudebakerGeorge

HOWEVER...I get sick and tired of people crowing about wanting better gas mileage...
StudebakerGeorge

Then why did you read this post?

Analog man in a digital world.

[PackardV8]

quote:the 1986 Mustang GT has a sequential multiple-port fuel injection system, 9.2:1 forged flat-top pistons, cylinder heads featuring a new fast-burn combustion chamber, roller lift cam and stainless steel tubular headers, fuel injection setup featured a 58mm throttle body (540 cfm) with 19 lb-hr. injectors and a tuned length aluminum intake manifold, H-pipe feeding dual converters, a Hall Effect distributor to be compatible with Ford's EEC-IV computer, base weight, depending on equipment, is 3500#.

A few reasons an '86 Mustang GT might be able to pull higher gears than a '50s Stude.

thnx, jack vines

PackardV8

[Studeman]

IMO... gear it to run 2750rpm @ 70MPH.. whatever ratio works best to achieve this. Studebaker engines have a nice "cruising" band that the engine works most efficiently. anything under 2400 @ cruising speed is lugging the engine- and she won't like it. 3000+ is over-revving.

I have a built 289 4-speed and have had a 3.07, 3.31, and 3.73 in it.. driving thousands of miles with each ratio...
The 3.73 was by far the better rear axle ratio- in ALL respects. Including gas mileage (18.6 all-around 20.2 hwy.
I though mileage would increase with both the 3.07 and 3.31... NOT!!! The car became a dog to drive, and mileage dropped 5mpg on the highway.
In the next incarnation- the car will get 3.73 gears re-installed.

Ray


Specializing in Studebaker Restoration

[Hippie]

The NOS 3.73's are on the way. Thanks for the replies.

Analog man in a digital world.

[GEEMAC]

Have a 63 D-HT with 3.45 rear to 700r trans slightly warmed up 305, what say you good bad or what.Car is not up and running yet redoing from dirt up, have frame finnished ,motor trans installed ,starting on sanding body really despise this job oh well can,t talk the lady of the house into it.any comments on the gearing neg. or pos. have at it. MAC

[Hippie]

That combo will work very well. 305 is torquey motor for it's size, the 3.08 1st gear will get it rolling very easily, the big drop to 2nd I don't like but doesn't bother some. I like the 200-4R myself but the 700 is good too. I had a '92 S-10 with 4.3 V-6, 700R4 and 3.08's. Got 26 MPG being driven like it was stolen and surprised a couple V-8 Dakotas. A 3.42 would have really made a rocket out of it.

Analog man in a digital world.

[buddymander]

True that the 86 Mustang GT practically tunes itself. That's why you can't just use factory specs on the Studebaker. You have to dial it in. Like that 289 4-speed that gets better mileage with the lower gear. Dat ain't right. I could maybe see it if it was an overdrive. The power curve on that motor is lacking at the low end. It needed to be dialed in timing wise, with the higher gear. I'm thinking that that motor is not making all of the power it could be, having a narrower power curve than oem.