Which flywheel weight??

Smokedawg

Founding Member
Jul 6, 2001
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Pulled transmission out of my 90 Mustang to do some transmission work. I ordered a new billet flywheel from LMR that comes with 28 and 50oz weights. By looking at the year of the car, it calls for 50oz counterweight to be used. There is a note that if running a 331/347 to use the 28oz weight.

My car does have a 347 in it, but I have used the factory flywheel in it in the past with no issues(besides burn marks on it).

What are your guys suggestions on what weight I should be running when I install the new flywheel?
 
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7991LXnSHO

wanna catch the space herp
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Sep 1, 2010
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The weight is for the counterbalance of the rotating assembly, not the weight of the flywheel’s total weight. So don’t drop it on your toe.
If you are sure the current one is stock and is 50 Oz balanced, putting a 0 or 28 Oz balanced flywheel on will give quite an unpleasant vibration.
 

Smokedawg

Founding Member
Jul 6, 2001
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The weight is for the counterbalance of the rotating assembly, not the weight of the flywheel’s total weight. So don’t drop it on your toe.
If you are sure the current one is stock and is 50 Oz balanced, putting a 0 or 28 Oz balanced flywheel on will give quite an unpleasant vibration.

Just pulled the flywheel last night and its stamped with the follwing:

Ford RF-E1ZR6380-A2A ...Looking that up, looks like its a factory flywheel
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
6,858
2,763
194
Kearney, NE
Just pulled the flywheel last night and its stamped with the follwing:

Ford RF-E1ZR6380-A2A ...Looking that up, looks like its a factory flywheel
Any mods to it? I suspect it could have been rebalanced, but stoker kits also have been balanced to all three weights. We are guessing on what you had done.
 

Smokedawg

Founding Member
Jul 6, 2001
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Any mods to it? I suspect it could have been rebalanced, but stoker kits also have been balanced to all three weights. We are guessing on what you had done.

Mods to the flywheel? I dont recall every having anything done to the flywheel except having it turned when I put a new clutch back in the day. I've tried digging through all my paperwork on the stroker kit I bought, but no luck unfortunately. Sounds like this kit may have been balanced to 50oz as I had no vibrations issues ever with the factory flywheel.
 
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