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I have a 65 Belair that started life with a 6 cyl with 2 speed powerglide and A/C. I recently replaced the engine with a sbc 350 and the transmission with a TH350. I'm told the TH350 is an early 80's vintage with a "universal" housing - ie. bolt pattern for chevy and Buick?.. Anyway, the speedo reads way high. I've read some about changing speedo gears and first thing I need to do is know the rear end ratio. Before I put transmission in I jacked up one wheel (other still on ground) and spun the wheel and counted the yoke revolutions. The wheel when 9 1/2 revs for 16 revs of the yoke. I calculated this to be a 3.38 rear end. Did I do this right? and is this a rear end that would have come with car?
Thanks!
Ed
 

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Chevrolet did offer a 3.36 :)

If you still have the original Powerglide ... pull the speedometer cable and bullet

Like this ..

count the number of teeth on the driven gear



and then count the teeth on the driver gear ( on the output shaft )



Divide the numbers and get the ratio difference ... then duplicate the same ratio in a Turbo 350 set and you should be GOLDEN ... :)
 

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you could at least show pics of parts that are close to what is really in a power glide...... :D
 

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Crosley said:
you could at least show pics of parts that are close to what is really in a power glide...... :D
True ... so true ... ;)

If I could find photos of a Power glide parts and pieces on the internet I would ... but the 700R4 stuff is all I could find ( and that what I have in the 3W ) ... :rolleyes:

They should be close enogh to give the guy a idea on what to do ...
 

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Discussion Starter #6
Thanks - I do have the original powerglide. I hadn't thought to check it. That's a good idea. One question - I'm not sure how hard it is to see the drive gear. How many different drive gears (ie. different tooth count) were available on a 65 2 spd powerglide? I was thinking I could rough out the gear ratio by turning output shaft and counting speedo gear rev. Then after pulling the driven gear out and counting, if I couldn't see the drive gear I should be able to figure out.
 
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