SLC Hubs/ race worthy

OT: Hi Mesa. That red doodad leaning against your battery. Could you tell me what it is and where to get one? There is one attached to a car I bought and I need the other half. Thanks,
That is one half of a quick disconnect plug, they are typically available at most race parts suppliers (Pegasus for one, probably Summit as well)
BTW: That is not the battery for the car, it uses a very strong Indura Power. Unfortunately I was in need of a stronger small battery over the Braille. Moved the Braille to the track car.
Just picked these up from Fran yesterday. May be another option for the hub upgrade.

That’s great - really love to see the continued development from the factory!

Are those the race balljoints?

Fran - how about a conversion kit for us guys who have the older uprights? Could you make up a set of spacers for the rear? I jumped and picked up a set of the Dulaney adapters for the front but will eventually need some spacers for the rear.

Howard Jones

Cam that looks like the whole upgrade right there. All you need is the bearings and the stub shafts it seams to me. John are you saying that the current production SLC (non race version) gets theses pieces. If so then this thread is pretty much complete. Just order this version from RCR and retrofit. Then you have pretty much exactly what I ended up with on my car. I wonder how much it costs.
I don't know if these will be the new standard or if they are just an option.

I also got a set of stub shafts from him so all you really need is the bearings.
Cool, John.
It's great to see these become available, very nice. Where do the spacers in the last picture go?

Mesa, yes, I'm very glad since I have been following this thread and was about to embark on the upgrade.

Not sure where those spacers go yet. I've ordered the hubs and will post progress pictures when the hubs arrive.


Ken Roberts

Spacers look like they get placed on the outside of each front upright. Since the front upright can be used for either side a removable spacer is need. If you look at the picture (post #267) you can see they are machined the same on each side of an upright.

The rear uprights also look to have removable spacers. The picture in post #263 shows them in place.

Instead of stocking four different uprights they only need two now.
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I exchanged brief texts with Fran today. There are new front and rear uprights. The center section of the upright and spacer will be available as an upgrade. The new rears will accommodate C5 and C6 bearings. The rear requires a new stub axle as the bearing has a thicker shaft with higher spline count. Fran hasn’t finalized pricing yet, but the numbers he shared with me seem inline with other approaches given that it’s a complete solution. I suggested that he also drill and tap holes for the parking brake bracket. So, if you’re thinking about doing your own upgrade I’d wait... I already placed my order.

The ball joint is the track day version which he doesn’t think I need... I think I passed the installing what I don’t need line a long time ago

Joel K

Great thread everyone. I have emailed Jim Dulaney and he is open to making another run of his wheel hub bearing adapters.

Looking for 5 more individuals who would want a pair. I prefer these vs. the others due to the fact they can use the C7 bearings which are significantly less expensive than the X-tracker hubs.

They are $475 for the pair shipped.

Roger Reid

In switching over to the C7 X Tracker hubs I followed Ken and Howard's footsteps. I machined the rear uprights to accept a machined Bushing/spacer. In measuring the C4 hub vs the C7 X Tracker, I required a .250" spacer. Ken had measured his C and C7 bearings requiring a .190” spacer. The difference may be that the C4 bearing when I measured was not compressed with a stub shaft bolted in. The C4 bearing might require the stub shaft to be bolted to tighten the bearings. Without the stub shaft being bolted in place the bearing is sloppy. Not so with the C7 hub. I can thin up my spacer if needed when I drill and tap the mounting holes for the brake calipers. The pics show that I measured the flange to flange distance on the C4 bearing then zero'ed my caliper. Then I measured the C7 bearing and you see the -.250" result.
The next pic shows the mounted C4 bearing next to the mounted C7 bearing with a straight edge across both of them.

Roger Reid

In post 183 and 188 of this thread Ken shows having a “steel bushing” pressed into the upright to maintain “hub centric”. As Ken says this is because the C7 X Tracker hub is 3.593” where the hub slip fits into the upright. The upright diameter on the C4 hub is 3.620”. A .027” difference. So a bushing is needed to center the c7 hub. I machined a spacer/bushing combination into one part. I machined the upright with a slip fit clearance for the bushing portion of my spacer. The spacer also has the new C7 X Tracker bolt circle at 4.567” as Ken states in post 210.

Roger Reid

The holes in the upright were machined to the new bolt circle of 4.567” (see post 210). Then the holes on the inside of the upright were counter bored .560” deep x .720” diameter for clearance. I also had a 4.065” x 45 degree chamfer on the inside for clearance to accept the new stub shafts from The Drive Shaft Shop. The Drive Shaft shop part is found here.
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