I have a 1950 3100, stock. I am thinking about changing the rear end gear ratio from the stock 4:11 to 3:55. If I do this what change do I need to make to the speedometer gear and the 3 speed transmission?
Last edited by ChevyDarren; 03/16/20243:49 PM.
Darren Current Project - 1950 3100 5 Window with a rebuilt 216 and 3 speed trans
Did that to my '50, years ago. Don't think you need to do any changes to the transmission but to add a speedometer adapter to where the speedometer cable connects to the transmission.
Craig
My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear My truck ....... Respect The Rust If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.
If you're running a stock 216, you'll find that there will be a lack of pulling power if you do "real truck" stuff like putting any kind of load in the bed. If you're running a "Cowboy Cacillac" that seldom if ever hauls anything bigger than an iced-down Yeti cooler to a tailgate party, you should be OK. 15 inch wheels will also help out in the load pulling department- - - 16's with high profile tires, not so much. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Put the 3:55 conversion in my truck a couple a years ago. Best thing i ever did. Can cruise at 70 plus with no problem. I also have a 235 with 2 two barrel carbs, headers and 3 on the tree. The 3:55 makes it more enjoyable to drive.
If you have stock 16" rims with 28" bias ply or 30" radials, and don't like how the engine struggles in first gear with the 3.55 gears, you can dial it in for more acceptable driveability by going to 15" with less than 28" tall tires (as HRL suggested). I had to do just the opposite with a 235 with a 4.64 rear gears, 28" tires, and a T-5 transmission. That combination made 1st gear an almost useless granny gear. I went to taller 30.5" radial tires and that dialed everything back in. It made 1st gear very useable and it also resulted in the ability of going 70MPH without the engine screaming in 5th gear.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
Yes, very happy. Note that my motor is a 235. Because of still having stock brakes and living in a crazy heavy populated area, I still don't go very fast in the truck.
Craig
My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear My truck ....... Respect The Rust If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.
I have a stock 216 w/3 spd transmission and 4.11 rear end with 16" rims and ~29" tires. I also live in downtown Atlanta and drive on the freeway during rush hour. No aspect of the original setup bothers me at all. I stay in the right lane and drive 55-60.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
