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How to upgrade turbo 400

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Old Feb 21, 2022 | 09:41 PM
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Lm7turbo's Avatar
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Default How to upgrade turbo 400

How do I upgrade my mainly stock th400? I have a reverse manual valve body, unknown Midwest torque converter[allegedly 3000), transbrake.

I'm not rich or smart enough to repair this this400, but aren't there a few basic parts that can make the turbo 400 make it to 750-800 wheel?

Any ideas or suggestions? Thanks.
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Old Feb 22, 2022 | 07:23 AM
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fwd hub
good valve body
34 element intermediate sprag. Commonly found in 4l80e transmissions
5/3/5 clutch count is PLENTY
get clearances and endplays correct.
For a true performance tans, even a 750hp unit, I have ALOT of time on the lathe and mill to make these right...but that basic list I just gave will be fine for a DIY guy that doesn't want a nice/fancy unit
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Old Feb 22, 2022 | 01:17 PM
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Originally Posted by MaroonMonsterLS1
fwd hub
good valve body
34 element intermediate sprag. Commonly found in 4l80e transmissions
5/3/5 clutch count is PLENTY
get clearances and endplays correct.
For a true performance tans, even a 750hp unit, I have ALOT of time on the lathe and mill to make these right...but that basic list I just gave will be fine for a DIY guy that doesn't want a nice/fancy unit
thank you for the detailed reply. I wasn't expecting to need that many parts. Looks like I have more research to do.

Thanks
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Old Feb 23, 2022 | 07:03 AM
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"that many parts"
it's 2 parts...and a good valve body...what are you talking about?
FYI this won't be a nice race trans...it will just be something that doesn't puke its guts on the track after 3 hits
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