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I'm thinking about swapping out the original two speed automatic transmission in my 65 GTO with a manual one. What are some recommendations on which one to get and where to get the conversion parts?
 

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Former Moderator
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If you want a four speed I would recommend a Muncie M-20. Still pretty plentiful and you should be able to procure a servicable gearbox in the $300 - $600 range. I would also recommend getting a factory service manual or the excellent GTO restoration guide by Paul Zazarine for diagrams of all the components.

Aside from the gearbox you will need - A flywheel (factory are cast iron which is fine for stock but you might want to consider steel if your budget allows), a bellhousing ( Pontiac, Olds, and Buick used a specific one, different from Chevrolet. Stock is cast aluminum, aftermarket is steel), clutch and pressure plate (lots of aftermarket support here), throw out bearing, and you'll need a clutch pedal and linkage as well as a different brake pedal (Manual are narrower).

Sticks are a lot more fun to drive if installed right.

If you are interested in an overdrive, I highly recommend the Tremec five speed. That is all dependant on your driving needs, your rear gear and your budget.
 

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64-67 Expert
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What ALKY said. M 20 is better than an M-21 due to it's lower first gear ratio. In CA, prices are $600 for a beater trans to $1300 for a done one. I've seen nice ones for about $800. The $$$$ is going to be in the pedals, belcrank (Z-bar), frame tab (labor) console (if you want one) and labor in general. This is not a cheap conversion, but it will change the feel of the car entirely. Another option is to pull the 2 speed auto and simply bolt in a TH350 auto trans. This alone will make the car feel like it picked up 100 horsepower. This is a far more cost effective option. (the 4-speed will also make it feel like a real musclecar too!!) Good luck........
 
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