Anybody out there know the transmission gear ratios for the 1954 Chevy passenger car (Bel Air) 3-speed transmission? I have searched long and hard, and have come up with just a few results, which do not agree with each other, except that 3rd. is 1:1. I am getting ready to select a transmission ratio set, rear end gear and tire size, to maximize efficiency at freeway speed, without killing the low end. I want to get a reference point to the original 1st. and 2nd. gears. It is not a hot rod, just a cool boulevard cruiser, with a mostly stock 235. The customer is not interested in wasting fuel, or his money.
Oddly, no. Thanks Don. I just re-ran all of my previous searches, and somehow, this is not in any of my results. I swear sometimes that the internets is plotting against me.
Just a thought, if the tranny is out of the car you can spin the input shaft in all three gears and count the output shaft revolutions. Don
The 235 will not like anything lower than a 3.50 ratio. Those older engines do not like low RPM at highway speeds ,you end up with larger throttle openings and less mileage. And I think you have some hills in your area ,hang a 3.00 ratio and sencond gear will get lots of use. Fuel mileage in the older cars was best gotten with small throttle openings ,high vacumm and higher RPM . And by higher RPM I mean something around 3000 at 60-65. Try turning a 235 at 2000 at those road speeds and your foot will be way into the throttle and milage will suck.
when working with tire and rear end. the only trans ratio that matters cruising speed is the 1 to 1 unless you add overdrive
Thanks John. I am still waiting on the customer to nail-down a tire size. Once I have that, I should be good-to-go. It will be a T5 5-speed, in any case, so there are a few gearsets to choose from. Rear ratio is up for grabs. It will be a mostly flat-land car, but will need to be capable of crossing the Sierra Nevada Mountains, at at-least 55. He's not expecting a miracle, just better than stock, if he can get it. As for cruising, this car does, and will continue to get cruised at 25-35, on a regular basis, so all of the gears matter.
'54 Powerglide rear gears work as well as anything, 3.55 ratio.(If you are keeping the closed drive) I had a '55 overdrive in my '54 with a 4.11 rear. It got better mileage in direct than in OD, like 5 MPG better! Later, when I swapped in a Duntov-cammed 283, it went faster in direct than OD, too. OK, I see you posted more info as I was typing. Still, the 4.11's with OD are about as high as I would go with a 235. It will pull OD on a hard, flat road with some gain over direct, but not much, I bet.
He seems to be leaning toward a radial tire that is a bit shorter than the stock size, so I am targeting keeping 4th, with the 5-speed, roughly the same as 3rd, with the 3-speed. That would get the car off the line a little easier, make low-speed cruising a little easier, and leave a little more on top for flat-ground, flat-out jamming down I-5 (nearly dead-flat).
Shorter that stock 6.70X15 my pick would be 3.70s. maybe .3.50 as a T-5 will have a lower first than the 3 speed I'll bet. But my fav would be the 3.70 for all around good performance.
Stock 3 speed gear ratios are 1st 2.94:1 2nd 1.68:1 3rd 1:1. Stock rear end ratios '49-54 216 engine 3.9:1 235 engine 3.7:1 'glide 3.5:1 Sent from my DROID device using the TJJ mobile app
I'm running a T-5 from an S-10 with 373s in a 10 bolt rear. Mileage does stink but it cruiese fine in 5th. It can still pull. If you want higher rpms looking for better mileage, stay in 4th. Dom
Ever one I have worked on 49 to 54 had 4.11 and 355.. maybe Oz has different ratios than USA?? Could be due to OZ is flatter and US has more mountains and hilly areas.
dunno. i know ford sold most cars with 4.11, until '40, then they went to 3.78. open banjos were 4.11 except in the rare Mercury utes, which were 3.78.
Yes; that is correct; 4.11 clear back to 1941 in my experience. We used to put P/Glide rear ends in the stick cars.
49-52 4.11 for sticks, 3.55 for Powerglides, although the Powerglide did't become available until 50; 53-54 3.70 for sticks, 3.55 for Powerglides. I am Butch/56sedandelivery.
I had a 54 in high school, they were pretty busy at the older highway speeds let alone 75 on an interstate today, an OD 3, 4 or 5 speed would be really nice in one
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