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Discussion Starter #1
There may be an older thread I missed about this question and if there is can someone direct me to it. I'm thinking of going to an automatic tranny for my 2.0 and I would like to know what set up would be good to go with.
 

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I think this is the first I have heard of someone planning to convert a manual car to automatic, but I honestly think the most logical approach would be to sell your manual car and buy one with an automatic.

Beyond that, you have not provided nearly enough information for anyone to make an informed suggestion.
As a starting point, is there a reason that you wouldn't want to use the stock 5L40-E? Are you aiming for something exotic like a dual-clutch?
 

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I agree with John,. I don't think you can do better than the stock auto tranny. I don't have one and haven't ever driven one but I know several owners that do and they all pretty much love that trans, especially in the "I" setting on the twisties.
 

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Discussion Starter #4
I can not power shift my manual transmission. I am more into drag racing the car. I have a spec clutch I purchased used and I installed a separate clutch reservoir and that didn't help. I have missed gears and the engine come undone. The engine has 353 RWHP and I think an automatic is the way to go.
Do you think the 5L40-E is comparable or better than a 350 turbo?
 

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It is always good to have all of the pertinent information. The issue with a transmission is torque, not power.

The 5L40-E is rated for 250 lb-ft of torque, while the TH350 is rated for up to 410 lb-ft, so in respect to strength it is certainly not better, and isn't really even comparable.
 

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Sounds like a great project for a Liberty's Gears T5. IIRC they rate them to something like 425ft-lbs. Not a lot of breathing room but should be enough, and they can put all other sorts of tricks in there too.

They aren't cheap, (~$2k out the door) but I bet by the time you were done it wouldn't cost much more than trying to swap an auto and hoping you can get the computers to talk.
 

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I think the trick to installing an auto would be to use an old-school one (Like the TH350) that doesn't need a computer, or is otherwise stand-alone.
The car wouldn't know that anything had changed once you worked your way around the absence of a clutch pedal to put a switch/sensor on.
 

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I think the trick to installing an auto would be to use an old-school one (Like the TH350) that doesn't need a computer, or is otherwise stand-alone.
The car wouldn't know that anything had changed once you worked your way around the absence of a clutch pedal to put a switch/sensor on.
"I" would know if it doesn't have a lockup torque converter or OD; a 2004R or 700R4 would be better choices

Bill
 

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Discussion Starter #10
This is what I'm thinking too, the tranny would not need the computer for anything and I could build one really reasonable with a 3500 convertor.
 

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Sounds like a great project for a Liberty's Gears T5.
The OP wants an automatic, not a manual trans. Interesting source for those sticking a T5 behind a V8 - they also have torque limitations that those guys may have addressed.

I think the trick to installing an auto would be to use an old-school one (Like the TH350) that doesn't need a computer, or is otherwise stand-alone.
Agree - there may be a some commonality in terms of programs for another modern GM automatic - the post 2015 8L45 used in the V8 Caddie or maybe the earlier 6L45 automatic might be made to work. Adapting a 10 year younger trans to older programming and TCM of a Kappa might be an expensive and lengthy job, though.
 

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The stock auto trans in kappa platform might be rated at 250 lbs of torque, but our cars are very light in comparison to the BMWs and SRX (equipped with the "same" auto transmission), so they can take more abuse. There is a guy who did over 700 1/4 mile passes on the stock trans without a failure, the first couple 100 passes he had the wr-1 and the upgraded to the wr-2 his best was 12.05 s at 116 mph. He decided to upgrade his converter and trans, because his 60' decreased with the wr-2. After upgrading the transmission, his new personal best time was 11.5. Now he is running a new turbo setup and he is expecting to be in the 10s. In conclusion if you are at 350 whp (torque should be pretty close) the stock trans should be capable to hold just fine.
 

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........ In conclusion if you are at 350 whp (torque should be pretty close) the stock trans should be capable to hold just fine.
The problem, if you go back to the original post, is that he has a manual transmission now.

Converting a manual transmission car to a stock auto transmission car is probably more of a challenge than converting that same car to a non-computer-integrated TH350, 2004R, or 700R4.

Given what you say about the capacity of the stock auto and depending on what other mods have been done to the car, I will go back to my earlier comment that the best solution might be to trade cars.
 

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Discussion Starter #15
I am still going with the old school 350 turbo and a custom aluminum drive shaft. They make a plate to hook the 2.0 to the turbo 350. I will have to fabricate a tranny mount. It should be a good winter project. No more hydraulic clutch or missing gears or blowing syncros.
 
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