help with th400 swap. what parts to buy?
#1
help with th400 swap. what parts to buy?
pulled my t-56 out. looking to put a th400 in. I am clueless w automatics. i know autos use a flex plate, now do i use a LS1 flexplate for a th400 or do i need some special conversion one? cant I just use a ls1 flexplate and have a convertor company make me a convertor that works for th400 mated to ls1 flex plate?
so far I got a th400 short tail lined up
-jw ultra bell
-shifter
-custom driveshaft
-UMI trans crossmember
I know i need a flex palte and convertor but thats where i'm confused.
what other parts will I need?
so far I got a th400 short tail lined up
-jw ultra bell
-shifter
-custom driveshaft
-UMI trans crossmember
I know i need a flex palte and convertor but thats where i'm confused.
what other parts will I need?
#3
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Gm makes a conversion to put a turbo 350/400 to a ls motor. I can't remember the part#. I saw it at scoggin dickey web site. It came with everything to change it over to mount the bellhousing to the ls with some spacers for the flex plate.Check there web site.
#5
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You can use the flex plate from a 6.0L too. Thats what I did. I was considering offering you a trade a few days ago for my TH400 for your T56, but I procrastinated and see now you've got most of it going on. Check out the thread on making the speedo work... VERY useful!!!
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uses a ls1 flex plate a sertifed one with the same bolt paterns to you torqe convertor bolts and a th400 tranny mount. a new driveshaft or modify yours. mad mans dipstick. shifter with cable and are you plan on running stock speedo you need a speed sensor and reculor wheel for the tail housing of the th400 and pig tails. and a tranny cooler. im pretty sure thats it
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uses a ls1 flex plate a sertifed one with the same bolt paterns to you torqe convertor bolts and a th400 tranny mount. a new driveshaft or modify yours. mad mans dipstick. shifter with cable and are you plan on running stock speedo you need a speed sensor and reculor wheel for the tail housing of the th400 and pig tails. and a tranny cooler. im pretty sure thats it
You can tap the ABS sensor to run the speedo.
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tap the front or rear ABS wires/sensor and adjust the PCM . . .
https://ls1tech.com/forums/automatic...350-th400.html Page 2 close to the end is most useful
https://ls1tech.com/forums/automatic...350-th400.html Page 2 close to the end is most useful
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Trenthqls1 (08-21-2021)
#12
You can use the flex plate from a 6.0L too. Thats what I did. I was considering offering you a trade a few days ago for my TH400 for your T56, but I procrastinated and see now you've got most of it going on. Check out the thread on making the speedo work... VERY useful!!!
#14
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tap the front or rear ABS wires/sensor and adjust the PCM . . .
https://ls1tech.com/forums/automatic...350-th400.html Page 2 close to the end is most useful
https://ls1tech.com/forums/automatic...350-th400.html Page 2 close to the end is most useful
That's the one.
#18
what i have found is you run a ls1 flexplate. then you tell the convertor company to custom make you a th400 to a ls1 convertor. the snout and bolt pattern will match a ls1 convertor. so then it becomes a direct fit. if you use a SBC convertor you need a spacer or adapter.
#20
Next time, copy and paste a link to the thread as they tend to move up and down as people post! Doing searches are not the easiest way to find them. I am looking to do a conversion from t56 to TH400 myself on a 1993 Trans Am and I havent found squat on the conversion no matter how many ways I ask the Search function!
Joe
Joe