Closed Rearend--Can I change gear ratios?

In my 1949 Fleetline, is there any way to change the rearend gearing besides converting to open driveline?
From what I am told. the stock 4.11 isn't going to cut it for the commute, unless I drive in the slow lane.
Yes, I did a search but didn't find the answer.
Thanks

Tucker

 

You can get a gear set from a Powerglide car, which has "taller" gears in the differential. Chevy introduced the Powerglide trans in '50, but the rear ends were the same on those cars going back many years... So, a 50 on up will have those gears and be a bolt on fix for your car.

It just so happens that I have a set. PM me if you're interested.

 

'50-'54 PG cars had 3.55s, and '53-'54 standard shift cars had 3.73s.

 

Are you sure it's not the other way around? I'm not calling you out or anything, but I did get this info from a very reliable source. I could be wrong, but I was told that column shift guys looking for a little more top end swap out powerglide rears. It may be that this works for the older cars, like from the 40s. Do you know by chance what the ratio was for a column shift '49?

Anyone?

If I'm wrong about this, I seriously appologise, 49. I will count the teeth tonight and give you the actual ratio.

 

I know that my 51 with a 3 speed has 4.10. I was under the impression that the powerglide cars have a 3.55. I know that you can get a 3.38 from Patricks Ring and Pinion.

 

Yesah, that's what I thought. I got my info from Patrick's as well.

 

Heathen's right about the ratios... and, yes, Patrick's has everything you need. Call him up he's a good guy.

 

Yeah, but what is the ratio for a column shift '49? I was under the impression that it was 4.10 like blown240 says. In that case, these gears would be "taller" and therefore better on the highway.

 

the bigger the ratio number, the faster the engine turns on the highway.

"taller" "steeper" "higher" "longer" and other such terms are kind of confusing, you know.

 

Exactly, so if you want your engine to turn slower on the hightway, you get a gear set with a numerically lower number....

 

Whoa, so the lower the gear number, the lower the RPMs at highway speeds? Is that right?
Marc--I don't know if I'll be up for Billetproof, but I'll let you know.

Thanks

Tucker

 

My truck with a 2.73 gear turns around 1800 RPM at 75 MPH; my '60 Pontiac with a 3.08 turned 1800 at 65 MPH.

As long as you're changing the rear, get the whole thing out of a 53-4 PG car and get the fromt backing plates and drums, and you can put the Bendix brakes on it - they're if nothing else easier to find parts for than the Huck that are on your '49 now.


The other thing you can do is change to an open drive setup - a T5 (5 speed OD) from an S10 is an easy swap, there's a number of late rearends that will fit, and you can still run a mid-three gear and cruise with highway traffic and not tax the 235 too badly.

 

Well, a rear swap is out right now--time and money don't allow. What I'm just looking to do is put some smaller ratio gears in the rear I have now. I just wanted to make sure that was possible...I was afraid it wasn't.

This is just a "simple" swap, right? Old gears out, new gears in?

Eventually, I'll be switching to an open rearend, no doubt, but for the forseeable future, I just want something so I can drive fast on the way to work. That's if I get the darn thing running!

Tucker

 

Setting up the gears in the "pumpkin" is not a simple in and out swap...so try to find a good used rearend complete if you can.

Also on the brakes, the 51-54 cars used the "good" modern Bendix type brakes, so find one of those and matching fronts if you can.

 

I did the same swap a few weeks ago on my 1951 3 speed Fleet. Replaced the stock 4.11 with a complete 3.55 Powerglide rear (1951). Simple bolt in job done in a couple of hours. Made a big improvement.
Do like me, try to find a good complete rear end from somebody changing to open driveline if you can.