Conversions & Swaps LSX Engines in Non-LSX Vehicles
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Correct flexplate

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Old Apr 20, 2010 | 07:26 AM
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Default Correct flexplate

Can anyone explain to me the correct flexplate to use on my setup? I keep reading conflicting information. I have a LS1 out of a 2002 f body with a dished flexplate. I read on one post that I need a new flexplate with spacer then the next post I read says I just need the spacer?? I want to retain my 2004R as it is a well built tranny and if I don't need the flexplate then I don't want to put out the cash for one. S&P says I must use both or I'll have major problems? Please help....
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Old Apr 20, 2010 | 08:09 AM
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Well you need the spacer, but you don`t absolutely need the flat flexplate

You can use the dished flexplate, but you will have to oval out the holes for the converter bolts (298 MM bolt circle)

The flat 6.0l flexplate has the 300mm bolt circle like the older th400 th350, 200r4, and 700r4 used so it would be a bolt on.
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Old Apr 20, 2010 | 08:51 AM
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Thank you,
will I run into any issues by modifying the holes?? Or as best practice just use a flat 6.0 flex plate and call it a day. I want to do this right the first time to avoid repair in the near future.
Thanks
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Old Apr 20, 2010 | 10:15 AM
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I have heard rumors that if you modify them you can get a vibration from the torque converter not being centered.....but the torque converter centers off of the nose (hence why you need the spacer) so I don`t see how modding the holes could make the converter off center.
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Old Apr 20, 2010 | 02:08 PM
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Originally Posted by cypress_33415
Can anyone explain to me the correct flexplate to use on my setup? I keep reading conflicting information. I have a LS1 out of a 2002 f body with a dished flexplate. I read on one post that I need a new flexplate with spacer then the next post I read says I just need the spacer?? I want to retain my 2004R as it is a well built tranny and if I don't need the flexplate then I don't want to put out the cash for one. S&P says I must use both or I'll have major problems? Please help....
https://ls1tech.com/forums/conversio...uto-trans.html
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Old Apr 20, 2010 | 02:11 PM
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I called Hughes and there telling me the spacer only. I'm gonna go this route to help
keep costs down and hope it dosent bite me in the butt later?
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Old Apr 20, 2010 | 04:46 PM
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You need the spacers to support the hub of the converter. It goes on after the flexplate. You will need to elongate the holes in the LS1 flex plate some to fit the earlier style flexplate pattern.
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Old Apr 20, 2010 | 07:21 PM
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Thanks Bo,
With all the hours of searching and reading I can't believe that I didn't come across that posting before? I'm getting tons of good info from this site. Hopefully I'll find some good info on wiring the ECM (Me and electrical are not friends) and on the A/C system? Thanks for the help....
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