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Hello everyone,
Do you guys know if the re-re diffs bodies (OT208) and chain drive (OT226) fit the original Optima?
And how about the original diffs internals: do they fit the re-re bodies?
Thanks in advance!

No and no. None of that is interchangeable. I needed it to as well but came up snake eyes. Wished they kept it all oe myself.

Thank you for the info!
Ouch that's disappointing, even if it's consistent with the idea of keeping the value of the original cars..
Out of curiosity do you know where the compatibility fails? The chain can only be too short or too long, but the diffs? Are they too wide for the original transmission housing?
Cheers

The diff housings that attach to the sprockets are made totally different. All metal, different design to handle modern power options. Nothing matches up unfortunately.

Fair enough.. I'll give up then.
I was thinking about re-converting my original Optima Turbo to chain as I've got belt in now.
I would have considered it if it could come at a reasonable price..
Cheers

Thinking about it again (it's just an exercise..), with the addition of OT221 the diff bodies get complete and I am pretty sure they would fit the original transmission housings.
Only doubt left is about the internal parts of the diffs: direct swap or they don't fit the new diff bodies?
Only way to find out is trying.. and I don't think I will do it!

slazzaro wrote: ↑Thu Mar 04, 2021 2:11 pm Thinking about it again (it's just an exercise..), with the addition of OT221 the diff bodies get complete and I am pretty sure they would fit the original transmission housings.
Only doubt left is about the internal parts of the diffs: direct swap or they don't fit the new diff bodies?
Only way to find out is trying.. and I don't think I will do it!

The rerelease diffs use the internals from the modern Ultima, so built completely opposite to the originals with the output shafts attached to the drive cups instead of the gears. If you are going to fit the rerelease transmission into an original chassis, you will also need to replace the gearboxes as well. The rerelease diffs use 15mm od bearings while the originals use 14mm od bearings. The only way they would fit is if you managed to find some 10x14mm bearings, which just don't exist.

If you want to check, just download the manual from Kyoshos website to see how they go together http://kyosho.com/eng/support/instructionmanual/legendary/legendary_index.html

Thia is valuable information.. I didn't check the bearings.
Well, we can say they did a good job in designing a similar car with very few parts directly compatible with the original.
Cheers

It is amazing how similar yet different the old Kyoshos vs the rere ones are. Kyosho spent some time and effort for sure to handle today's big power. IMO I would just rather have them just the way they were in the past.

The front gearbox is not the problem when upgrading to Rere drive train. There you still have options. The problem is the orginal rear gearbox would have to be replaced. If you wish to upgrade to a slipper, without the diffs and belt, that is possible with the original gearbox. You'd be better off just replacing the rear gearbox.

I'm attenpting a "mish Mosh" on mine. It has the original Option House belt conversion. I'm going to put the one way front diff, in the original case, the rear will be all new, down to the ball diff....

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