Anybody with low gears drive on the freeway?

What rear do you have in your Ford? If you have a 9" the hogshead and gears are easy to remove, other than being heavy. Most 60's & early 70's 8 cylinder trucks have 3.25 gears, could grab one from a pull a part and try it out.

In my late model Ford F100 ('71) I have a 3.70, but with an AOD so it is about a 2.48 once it shifts into o/d.

 

4:56 rear, new 700R4 overdrive ****** made the world of difference from the 350 turbo I pulled out. I can now run down the interstate and still have a decent hole-shot from light to light. I do have 32 inch tires in the rear but smaller 29 inch slicks for the track to gear it down more!!

 

I started driving my 32 with 2.73's and 31" tall tires.

Calclated out to 200 mph at 6000 rpm.

I had the aforementoned 462" Buick in it, backed up with a T-400.
No problem drivng off from a stop.

 

My dodge & deuce both have gears with mid 2.50 great on gas & rpm's

 

JEEM, my wagon had 253 or 279 rear gears with a mild 327 (350hp).. its was a freeway flyer.. happiest at 85 to 90.. but sluggish off the line,,, thou pull up to me on the road doing 45 or more and i would put the money on the wagon...(down shifting into 2nd at 55 and standing on the gas was fun)

 

Back before OD most cars right from the factory ran around 3000 rpm at 70 mph. If you have a tach in the daily run it at 70 mph without using OD and I bet it'll run close to that

 

My Morris has a baby Buick in it, the aluminum 215 cubes that the Brits bought off Buick years ago. I have a 3.9 rearend and tallish tyres, but I still buzz along at 4000 rpm at 80mph. It don't seem to hurt it on the highway, but I tend to stick to 65-70 most of the time. It has a 3 speed GM180 autobox on, I really wish I had another gear to shift up to though.



Here's where I ran out of gas on the motorway (Interstate to you guys) last weekend. Didn't get quite the gas mileage I thought I was getting. Too much right foot I think

 

Took my Twin-H Hudson to the Hot Rod Cinematic this year,
2800 mi. round trip with 4.56's... Thank God for OD, brings it
to a 3.28 final drive. Cruises 70-80 without grief. Even so,
I can see a 4.11 in its future...

 

I've run 4.11's and 30" tire in F100 for decades at 55 MPH. Radio is out of the question at highway speeds. When avg. speed jumped to 80 MPH, I put in OD trans.

 

I used to run my 52 chevy truck with 4.11 rear daily for about 5 years.
Swapped the ring and pinion to 3.55 and never looked back.
Perfect ratio with a 1:1 ****** for city and freeway.
You can run a straight 6 at 2500-3000 rpm all day, going between 65-75 on the freeways.

 

4:11s and th350 with 30" tires in my A I like to keep it around 60 mph (roughly 3200 rpm) but am putting in a 700r when I get home cause I like burnouts and cruising equally (it had 2.56 before the gear swap and was a pain in the *** until about 30mph it wouldn't take both carbs but would cruise at 85 at 2600rpm) and 4.11s are fun I can't wait for a lower first gear and an O/D best of both worlds

 

my panel has 4.11's in it and on the freeway i stayed at 50-55mph (no tach but sounded about 3500rpms), now with the o/d trans it's about 2200 @ 70.....way better.

 

I´m running a 3.36 rearend with 29,3" tall tires on my 34 Plymouth. I´m cruising at around 80 mph @ about 3000rpm. Fastest I´ve been was 5500rpm in third, that makes around 143 mph.
My old tires were only 26,7" tall. Of course the car was a lot faster off the line, but chasing late models on the autobahn became annoying...
Chris

PS: We have no drag strips around here, so low gears make no sense to me.

 

i used to run 4.10,s in my 50 with a 400 sbc and a 4 speed 60 i was doing 3600 rpms put a 350 crate motor 4 speed with 3.37,s a like better on highway and still fun at stop lights

 

If you can locate a wide ratio muncie, used by GM in the 60's at least, then I'd bet you'd find a 3.08 works great! It is more efficient in terms of power band and mileage, when you use 1:1 ratio for final top gear driving. Then at lower speeds you are simply looking to have enough "overlap" of the power curve in each gear, w/the Mucie I ran the first three gears, and the fourth was a 1:1 "overdrive". Any other 4 speed trans would offer similar gear spreads in a rod, if it was wide ratio in design.

 

deucephaeton is right kids. with my 700r4 i have a 10.00 to one low gear and a 2.50 final, best of both worlds.

 

3.73 i drive it about 100-150 miles a week. it runs 3000 rpm at 60-65 mph. i put nearly 20-30000 miles on the 327 i use to run with no problems. id rather burn out at the light than cruze on the freeway. but thats just me

 

3.80 rear 51 merc flathead cruzes at 70 mph at 2,000 rpm.97 mph at 3,000.
tremeck 6 speed priceless .

 

Drove the roadster 110 miles one way to El Dorado Dry Lake last Saturday.
Still have the 3.70's and 30" tall tires.

Ran 70-75 on the way up on a cool morning.
Got just under 17 mpg.
Engine spinnin' along at 3000.
Vacuum gauge floating between 16" - 16 1/2".

On the way back, 80 - 85.
Didn't check the mileage yet, but even with the engine cranking off 3500 rpm mileage shouldn't be too bad.
Tailwind and running 17" on the vacuum gauge are good indicators of better mileage.

For the most part, highway driving.
A little bit of in-town running in Boulder to gas up.

Nailed it somewhat getting back on Hwy 95 from the dry lake and also leaving Rosie's Cafe.
Hey . . . the place was full of bikers . . . who could resist?

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After hearing Wingnut'z 19 mpg from his 455 Olds running 2.74's - roadster? - popping in a set of 3.25's sounds good.

There was a big performance jump going from 2.73's to 3.70's so I'm not gonna make too much of a highway flyer out of it.

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Morrisman, great little car.
Got any other pic's?

My pal built a 1938 Morris 12 4-door.
Suicide doors on all 4 doors if I remember right.
On the front for sure.

Your Morris looks similar from the front except for the lack of stock fenders.

Kinda funny, he got it started, worked the bugs out etc. painted it and all the while it had a 231" naturally aspirated Buick V6 with T-350.
S-10 rear axle fwiw, they must be tough, he was forever burning rubber in the car and never broke anything.

Anyway, I got my 32 running with big cam, dual quads etc.
He came to visit, drove it, liked the power, went home and stuck a mildly built SBC 350 in it with a different T-350 behind it.
Still had the S-10 rear axle, still didn't break it.

He did the job in about two weeks including recessing the firewall a bit and didn't scratch the paint.

If you have the California Hot Rodder book there's a couple of good pic's of the car near the back of the book.

 

4.88s run 3500 rpms with a over drive in the old pickup. Got sick of shifting in town and put 3.23s in. Much more enjoyable to drive now. and can run 100 at 2800 rpms now.

 

I always blast past the Biker hangouts and we exchange "thumbs-up" salutes...!

I was calculating my ge****ts with the engine sweet spot and have determined that a 3.25 ge****t should be the best middle of the road ge****t for all around driving... but I want the car to launch like it did with the 3.74's and cruise like it did with the 2.74's and the only way I can achieve those results is to utilize a 700R4 ******!

Again I'd like to know what the percentage the overdrive offers???

The percentage will help me determine what ge****t would be the best...!

 

We run 3:73's with our 6 cylinder. Throw into that equation that we run 31" tall cokers too, but nice all around gear for pick up and not running too many RPM's at highway speed.

2500 puts us around 65-70.

 

I keep hearing that 30% is the difference.
True as well with the 50's era OD's from what I understand.

An OD trans in the 32 with the 3.70's would be the best of all worlds.

Geez . . . maybe I ought to yank the 32's T-400, stick that in the 31 - another hurdle crossed - and do an OD automatic for the 32.

Right now, the 32's a little more civilized than the 31 will be so what the heck....

Doesn't look like it in the photo's I post now and then, but I am making progress on the 31.
Got an aluminum radiator a couple weeks back.
Centerlines and slicks.
A Gennie Shifter E-brake.
A pair of 6" wide slot mags for the front so I can change back and forth . . . maybe, I like the steelies and caps really well.

Along those same lines I found a pair of 4 1/2" wide 15" slot mags with 4 lug holes that look reasonably easy to convert to 5 lug.
It'll require some additional machined pieces, but that shouldn't be too difficult.

And, weird as it sounds, I've been looking for some 8 x 15 slots and found a pair of pretty clean 7 1/2" wide 15 inchers.

Trying to get a good start on the carport and get the big workbench/body stand cleaned off so I can yank the body and do some plumbing etc.

 

I like the highway gears 279 or 300
I have a 302/c4 and 279 gears in my F1 IM building. Its sole purpose is to go on trips.

 

With all of the options available when it comes to overdrives, there is no reason not to have one. From T-5s and T-56s to AODs, 200R4s, 700R4s, 4L80s and bolt on units both old and new, there is something for everybody.

Keep your big gears and just overdrive it.

 

On my 31 5 window Olds I put a big block 455 with 247-1 gears. I did this for a very specific reason. With 500lbs of torque and a 2200 lb car, I don't care what gears you are running, the tires won't hook up. Also, if I do the math right, at 65 mph, the car will be turning out 2100 rpms with 31 inch rear wheels so I won't kill myself with all the engine noise.

I will let you all know when I actually drive the car fopr the first time and see if my math works.

BC

 

The 700r4 overdrive gear is .7. So yeah, a 30% reduction.

Oh, and those aren't their thumbs they are saluting you with!

 

have a set of taller tires to put on for the highway

 

If it stays fairly cool at speed,but then gets hot at stoplights,is the fan pulling air through the rad?Does it have a fan shroud ?Yes, the low gearing will contribute to heating it up,but check the basics before you spend $ .

 

I've got 4:11s in my T roadster, TH 350, 29" tires, 4000 rpm running 80 on the highway. Longest distance I have ever driven it is from North Texas to Joplin couple of years ago, 8 hrs running 70 to 80. Very Tiring. 1 to 1 /12 hr is ok, anything further messes with my bad back.
I bought a '27 T coupe earlier this year, has a 12 bolt with 4:56 in it. I'm not even gonna try driving it any distance.