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Switch to OD?

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MadRiver

MadRiver

Jedi Knight
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As indicated in my other post, I have an unhappy tranny. Should I take this opportunity to switch to overdrive? It wouldn't be original for my car -- what do people think?
 
Depends on the quality of originality you want to maintain.(Concourse?)........

I prefer having the extra gear, better fuel economy & less stress on your engine

"mine are always built to drive"
 
In a word (or two) - Do it. I did it for my TR4A last summer and have been happy ever since. I did it to my TR3A back in '88 and have never regretted it (though the TR3A was originally an OD model it just was not working).
 
I'm curious - are you considering adding an o/d as an alternative to a 5-sp conversion, or in addition to rebuilding your 4-sp?
 
True story, 1975 I was having my clutch replaced at Mountjoy's Autoshop here in Maryland. I was thinking, man I wish I had OD. Called up Tim and asked him if it made any difference if I brought him a different trany to put back in, He said no problem. Went to a local junk yard picked up a trany with an A OD for $450, They charged me next to nothing to wire it up, sold my old trany for $300. Total cost about $200 installed. When I bought the 73 TR6 that I have now I made sure it had OD. Imagine my delight when pulling away from the previous owners house I hit the switch in 2nd gear and the OD kicked in. I had assumed it to have a J OD but I was happy to be wrong. When getting squirrelly on the twistys having 2nd OD is sweet, not too good for the U joints though. Get the OD and you'll never regret it. Phil
 
I switched over last year in my TR6 and it was a bit expensive, but worth every penny. If you want a recon unit, go to Quantum Mechanics. John is the best in the business and his work is guaranteed.
 
I did the switch about 3 years ago on my TR3. It's a driver that I put 6-7,000 miles a year on. If I were to do it again today i would go with the 5 speed convertion.I drove one not long ago, the shifts were greatand overall it is a much less complicated setup. No electrical compoents.
 
i read that the overall end gearspeed for an original overdrive unit and an original 4 speed are the same (give or take a small bit), due to the different differentials provided with the different setups. do most people change to a different differential as original, or keep their smaller differential. either way it would lower the mpg and rpm, it just wouldn't affect the speed. sorry, i guess i really don't have a question, except for someone to tell me i'm right or wrong. i'd love to do a changeover in the future but will log some miles on my original tranny for now.
 
Brosky, do you have contact info for "Quantum Mechanics" ?
Googling this is obviously useless (several million hits of the scientific nature)
 
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