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Couterbalance

Old 09-22-2015, 07:36 PM
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Couterbalance

OK, I have an auto car, and just bought a 4 port Manual engine from a JDM importer. I want to use the JDM 4 port engine parts to build a replacement motor as my auto 4 port ate an apex seal and I lost a housing and a rotor.


I would like to confirm the following: (Which I learned by searching)


I need to take off the flywheel and front counter balance from the manual engine and use the flexplate, front and rear counterbalance from my old engine in the final combination. Is this correct that the front counter balance needs to be changed?


I assume the Eshaft is the same in both engines, and that I can use the manual engine eshaft with the manual engine rotors. coupled with the other rotating bits paired for auto use.


Is it that simple? remember its going back in my Auto car, and I'm not revving to the moon.
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Old 09-23-2015, 01:41 PM
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you're correct. the m/t flywheel obviously needs to come off, and in its place goes the a/t counterweight and flex plate.

the front counter weight is a different part number between m/t and a/t for some reason, so if you have the engines apart, you might as well use the a/t one.

e shaft is the same, except the m/t shaft has a pilot bearing, so you should pop that out, or use the a/t shaft (it may not matter? not sure if the a/t uses that hole at all)
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Old 09-23-2015, 04:57 PM
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Thank you. I forgot about the pilot bearing, I will have to check on that. I plan to use the Manual motor Eshaft because the rotor bearings are worn to that. I looked up the front counterbalances and they are different part numbers so I will compare and take photos.
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Old 09-23-2015, 09:18 PM
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the e-shaft is the same , like j9 said it's just pilot bearing, both have the same hole, just the mt has the bearing already installed (when new) thats about it.

the counterweight has something to do with the weight, AT/AT was designed to be as close to balance as possible, on MT, it was designed to balance the MT stock flywheel, the At rear counterweight when used with MT front, the weight will be slightly off, nothing major, it works, but not that great if you do constant high rpm.

ACT sells a counterweight that they claim is better balance than stock AT counterweight, I have it in my MT 8, for some reason it does seem to have less vibration than other MT cars with stock counterweight, maybe its just my *** dyno telling me is better.
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