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After tearing up two SC-56 diffs at the Nordic Vintage Challenge I'm trying to find a diff that'll fit the vintage gearbox but is a bit more durable than the standard diff.

I've heard of the Thorp Dirt Burners 4630 Ball Diff and saw one back in March on Ebay for $150 when I've heard they normally range around $300.
Unfortunately I didn't have the money for it at the time and now it's long gone.

Are there any other options I can search for?

I'd hate to put a re-re gearbox in this car but I'll probably get one anyway just to have as backup at the next NVC event.

There might have been some more obscure branded ball diffs but I don't know of any other than the thorp.



The issue I see with using a vintage thorp is that their not that great of a design in the first place and it will eventually wear out. Parts are almost non existent. I think your best bet is a rere gear case and diff.

MIP made diifs too. The C200 and C400. These are even rarer than the Thorp.

Forgot to mention that Nodis made a ball diff.

How about an original Kyosho diff? Can't be more expensive than the Thorp... and probably a better design too.

Then again, a re-re GB will do the job for a lot less cash

Lonestar wrote:How about an original Kyosho diff?... and probably a better design too.

HatTrick wrote:After tearing up two SC-56 diffs at the Nordic Vintage Challenge.

I guess the stock stuff wasn't up to snuff.

Jim - indeed. I missed that

Well, I've ordered three brand new original SC-59 diffs plus I Helicoil-repaired the threads for the locking screws on two fixed spur gears as backup so hopefully I'll have it ready with spares for the next event.

Gonna order a re-re gearbox to have as a last resort backup as well!

Also gonna try to find an unused vintage gearbox housing. Maybe the one I have is worn in a way that makes it difficult to shim the diff properly which in turn causes it to shred the planetary gears.
Other than that I can't figure out why it would completely shred the gears on two diffs...

There are differences between the vintage gearboxes. Some have grooves that the "side plates" of the diff go into, and there are others without the grooves. Make sure you have one WITH these grooves....

But then again, you can't go wrong with a re-re gearbox....

TomEG wrote:There are differences between the vintage gearboxes. Some have grooves that the "side plates" of the diff go into, and there are others without the grooves. Make sure you have one WITH these grooves....

But then again, you can't go wrong with a re-re gearbox....

Yeah, I noticed those grooves when I got to borrow a diff from another participant at the last NVC. His old Tomahawk had them.

My Scorpion which I´ve owned since ´83 doesn´t have those grooves and I´ve never replaced the gearbox itself, only the gears.

Remember that the differential wasn't even an option for the Scorp when it was first released in 1982, nor for the Beetle in 1983. When they later released the diff as an option (and standard on the Tommy -84 and Turbo -85) they also made new gearboxes, with the grooves to stabilize the diff. Those revised gearboxes were issued with all models in the line from that time on. I've talked to Kogawa about this, and the oldest gearboxes are not suited for the Kyosho diffs. Those oldest gearboxes were inherited from the Rally Sports series.

Thank you very much for that info!! I had no idea about that!
I'll keep my eye out for that on Ebay!

I had a MIP C400 a couple of years ago and had no idea of what it was for, I think shodog identified what it was for me and I sold it on eBay but don't recall if it sold well. Here's few pic's that I used on eBay and sorry I can't help this is probably totally irrelevant but all I could add to your post.

I'd love one of those diffs!

Too bad they cost an arm and a leg if you can even find one...

Man that MIP diff for the scorp is super!!!! That would be the way to go. Thorp diffs are very built proof but SOOOO heavy, wish they had used titanium , well the MIP would be an upgrade from the thorp, less wight, and low inertial, I would think the MIP to be very rare, WOW, and yes the nodis is even rarer, I think it was a geared diff?

Here is a pic

http://www.tamiyaclub.com/forum/index.php?/topic/28732-scorpion-ball-diff-lexan-rc-box/

The guy who had this sold me a huge scorpion parts lot back in 2012, I won it on ebay, first jump into the wonderful scorp chassis build, sold the rest and made my money back, I asked the guy about the nodis diff, said it was sold for 400 GBP! it had tufnol material for gear - very tough and wear resistant composite.

Lars has a rare kyosho works diff for the scorp, its a ball diff.

Hattrick -
And I finally got that thorp diff on ebay that was there in March, I was surprised no one was buying, negotiated on $130 and I got it, Now I have 2 for a 4x4 beetle build! Thorp also initially made a fixed diff like the first nylon kyosho fixed diffs, Its the same as the ball diff version, same brass gears. Hey with oil in the sump, the gears should run fine without wearing much, what do you guys think?

Also I would go with the new re-release gearbox, its virtually the same design and does not look modern at all, I don't do any serious races so vintage stuff is good enough for me.