Diff cup compatability
 

So I was wondering which 1/8th scale diff cups are interchangeable. I know that ofna, hot bodies, and kyosho use the same cup.

HPI savage cups have a larger area for the bearing to sit on, but the internals look to be identical, are they?

Any other cups that will work? And internals? Just looking at all of my options to put together a kit for a center diff for the new emaxx and erevo. I want to offer the best choices in cups and gears if I sell it as a kit, just to give people options.

I have Mugen, Kyosho, Ofna, Hot Bodies, Savage cups in my parts bin. The savage also uses the same bearing (8x16x5mm) like the aforementioned ones. Just remember that the Ofna ravager, mutilator uses paper gaskets while the Hyper 7 uses an o-ring between the cup and ring gear.

I think I still have measurements of everything I mentioned somewhere in my laptop.

Sportwerks and Losi are same. The internals vary (3 variations), LST and muggy have unhardened spiders (silver color) with shims. 8's have no shims on the spiders but shims on the output gears (above the o-ring), not sure if they are hardened (black in color). I like the sportwerks internals; they are hardened (bronze color) and have shims on spiders. Losi also has new diff cups out that have steel inserts for the cross pins (on my shopping list).

I am actually looking for a diff cup that has a metal 8mm output that will take a 8x12 bearing. The savage cups use a 10x16 bearing. Ofna, hotbodies, and kyosho use 8x16 bearings.

I need the 8x12 bearings to fit the erevo tranny as it uses 6x12 bearings stock for the output shaft.

This sucks, as I have a bunch of savage diff cups. They are al, and I feel the plastic ones would be fine. I may have the machinist turn the savage cup output down to 8mm, that way I can benefit from the improved internals with the steel blocks that support the cross pins.

The internal gears on the losi diffs have smaller cross shafts than the hot bodies hardened gears. I tried to put them in the lst diffs, but no dice. Oh well!

I have that traxxas erevo/emaxx diff coming, I ordered it today from lower IL to upper IL so should get it by Saturday Link, Dunno if it will help unless its a different size


edit: I know it will be a pile but its my money so pffft !

Those are weaker than the 1/8 scale diffs :lol::na:. Traxxas only uses 4 spider gears inside compared to the 1/8 scale which uses either 6 or 8 spiders. More surface to dissipate the tensional and torsional forces inside the differential cup.

My Hyper 8 used a Kyosho spur gear with a Savage X aluminum diff cup and Hyper 8 (Ofna, Hobao) internals. Shimming was required, but I think that's to be expected.

I agree on the shimming. I shimmed all my diffs (6 and 8 spiders) :intello:.

what about buying the kit and putting the gear on a better diff cup & internals, and still use the shafts......i may end up doing that myself....any ideas on this

Look George, I dont know what part of my edit you didnt understand. I am aware that any diff that needs 500k lol must be running low on the spider gears. If I wanted your input I would have flown to Japan and ordered you a saki while debating blowfish culinary techniques. Again thanks for kicking me :party:

Damn, why so hostile? You're mighty cranky today as shown by your reply here and on the other thread by Patrick.

By the way, I don't like sake (not saki). If you're really aware about the need of 500K oil and low spider gears, why bother posting about them :rofl:.

Just tell your wife to hide the baseball bat so you don't hit your kids after you run out of tv's to hit :na:.

LOL man, Its all in jest. Sake is good stuff at least was back in the drinking days. I just found out the diff goes in the tranny, it doesnt have like diff braces to replace the tranny, what a pile. I was hoping it was like the cool things Mike made but in a cheap $35 aluminum cheesy version for fun. Guess I wasted $35, c'est la vie


edit, i never baseballed my TV, I have LCDs , think im that crazy

Funny, it is not a slipperential! You may like my setup, should have it done soon...

Yeah man put me at the top of the list. I was all excited for a few hours just to find out it goes in the tranny, wtf. I have no issues with the tranny, thought it would be cool to get rid of the whole thing though and go to a diff