Converter hits flexplate bolts
Thread Starter
Staging Lane
Joined: Jul 2015
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Converter hits flexplate bolts I am bolting a th400 to a LS and before the converter pads touch the flexplate the flexplate bolts hit the converter body.
anyone come across this before ? can i push converter into trans, come out 1/8" towards motor, throw washers in between and call it a day ?
https://www.summitracing.com/parts/sum-700361
^^ using this converter
anyone come across this before ? can i push converter into trans, come out 1/8" towards motor, throw washers in between and call it a day ?
https://www.summitracing.com/parts/sum-700361
^^ using this converter
TECH Junkie
Joined: Nov 2013
Posts: 3,913
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From: White Bear, Mn
As far as just putting in about a ½ in. washer as a spacer I don't know about but something like this is the right way to do it.
https://m.summitracing.com/parts/sum...FZiIswod5YsKEA
https://m.summitracing.com/parts/sum...FZiIswod5YsKEA
TECH Junkie
Joined: Nov 2013
Posts: 3,913
Likes: 366
From: White Bear, Mn
From the converter pads to flex plate should be about .125" - .250" .
If more than that you will have to shim with washers.
Thread Starter
Staging Lane
Joined: Jul 2015
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But shouldn't the converter be able to slide all the way forward to touch the pads without hitting the flexplate bolts I have installed transmissions and converters before and never can across flexplate bolts hitting the converter before the converter lads can touch the flexplate
11 Second Club
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I am bolting a th400 to a LS and before the converter pads touch the flexplate the flexplate bolts hit the converter body.
anyone come across this before ? can i push converter into trans, come out 1/8" towards motor, throw washers in between and call it a day ?
https://www.summitracing.com/parts/sum-700361
^^ using this converter
anyone come across this before ? can i push converter into trans, come out 1/8" towards motor, throw washers in between and call it a day ?
https://www.summitracing.com/parts/sum-700361
^^ using this converter
I used the Hughes Th400/ls1 spacer ring for the back of the crankshaft. And a B&M sfi flexplate.
Make sure when you are doing the install, that your converter isn't bottomed out in your trans pump. You need to pull the converter forwards a certain amount, but not too much. Follow their instruction sheet.
From memory, mine worked out with using about 1/8" thick washers between the converter and flexplate. It is working flawless
Edit: Yes you need to push the converter in all the way so it bottoms out in the trans, then pull it forwards the recommended amount, and use the correct washers to make up the gap between the converter pads and flexplate.
Last edited by Launch; Jan 29, 2017 at 06:33 PM.
Thread Starter
Staging Lane
Joined: Jul 2015
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yes as per my measurement a 1/8" washer will give me the 3/16" converter to transmission spacing and clear the bolts HOWEVER ... i am curious as to WHY the bolts are hitting if the converter is pulled all the way forward.
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11 Second Club
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Edit: You have the factory GM spacer. Well you still shouldn't have an issue, I used that one my previous LS1/th400 car.
Last edited by Launch; Jan 29, 2017 at 07:23 PM.
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Verdad Gallardo 11 Second Club
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With the Hughes style TH400/LS1 spacer, you run the standard length flexplate bolts and bolt your flexplate straight up to the back of the crankshaft and don't have the bolts sticking out like they do with the factory GM spacer.
If that makes sense.
Thread Starter
Staging Lane
Joined: Jul 2015
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If you use the Hughes spacer instead, your flexplate bolts won't be hanging out so far. Possibly that Summit converter has such a thick anti ballooning plate, that it is too close to the flexplate bolts, because of the GM spacer having the bolts sticking out further than normal.
With the Hughes style TH400/LS1 spacer, you run the standard length flexplate bolts and bolt your flexplate straight up to the back of the crankshaft and don't have the bolts sticking out like they do with the factory GM spacer.
If that makes sense.
With the Hughes style TH400/LS1 spacer, you run the standard length flexplate bolts and bolt your flexplate straight up to the back of the crankshaft and don't have the bolts sticking out like they do with the factory GM spacer.
If that makes sense.
i believe you hit the nail on the head.... i think its just the design of the converter that is causing this as i am using the gm spacer.
so my options are ....
hughes spacer or ... ???
11 Second Club
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11 Second Club
Joined: Jan 2003
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That thing above looks weak for any decent HP. I got this cheap B&M and not be afraid it shatters into pieces... https://www.summitracing.com/int/parts/bmm-20340
The only thing, that B&M one needs one hole elongating for some TH400 converters. So bolt it to your converter first before putting it in the car, if one hole is a bit off, fix it with a die grinder.