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1957 chevy bel air 4 door hardtop
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Hey guys a few months ago I got a 3 speed overdrive trans for a good deal out of 56. I have the stock 3 speed in my 57 at the moment. My car came with 3.55’s originally but after checking someone swapped a 3.36 rearend out of a 1960 Chevy. I’m not one to go fast or beat on it, but I wanna be able to drive highway speeds no problem. I was wondering how it would be to have an overdrive on a 3.36. I do around 3k rpm at close to 70. I have a 350 with a 4 barrel, and I upgraded to an 11inch clutch. Thanks guys!
 

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Hey guys a few months ago I got a 3 speed overdrive trans for a good deal out of 56. I have the stock 3 speed in my 57 at the moment. My car came with 3.55’s originally but after checking someone swapped a 3.36 rearend out of a 1960 Chevy. I’m not one to go fast or beat on it, but I wanna be able to drive highway speeds no problem. I was wondering how it would be to have an overdrive on a 3.36. I do around 3k rpm at close to 70. I have a 350 with a 4 barrel, and I upgraded to an 11inch clutch. Thanks guys!
I think it should work fine. My guess is that engine has more torque than a 265 did in the day so be carful with the clutch, but it should also drive well with your tall gears at highway speeds. In overdrive your 3000 RPM will be reduced to 2100 RPM with an equivalent rear end ratio of 2.35:1. That is pretty high geared and if it bogs down on hills you'll have the kick-down system available or just shift it into 2nd gear.
Keep us updated on the swap... Al
 

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I think it should work fine. My guess is that engine has more torque than a 265 did in the day so be carful with the clutch, but it should also drive well with your tall gears at highway speeds. In overdrive your 3000 RPM will be reduced to 2100 RPM with an equivalent rear end ratio of 2.35:1. That is pretty high geared and if it bogs down on hills you'll have the kick-down system available or just shift it into 2nd gear.
Keep us updated on the swap... Al
go for it. I like that gear. Keeps the rpms down at highway speeds. I don't beat on my car so I don't need a puller gear out of the hole.
 

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Your OD ratio (.7) is the same as my auto trans OD ratio.
With a 3.36 rear & 28" tall tires I see 2100 rpm @ 70 mph. Add about 200 rpm for your set up without a locking torque converter.
 

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🐔County, TN. 55 Bel Air Sport Coupe
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Just swap the tranny then and decide on the gears! Best way I can think of.

I'm doing that with an overdrive and 4.10 gears. If it's too many rpm's I can re install the 3.42's, or get something in between.
 
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