SLC Hubs/ race worthy

[Howard Jones]

Brian, I think these are the same ones referenced on post #46. At that time they were no longer available from that source. You might call the one you found and see if they have become available again.

 

[Roger Reid]

I ordered the Strano adaptors and c6 X Tracker (30 spline with passive sensor). I wanted the passive sensor because I may incorporate traction control in the future. The Strano adaptor uses 12mm bolts to attach to the hub as the X Tracker is also 12mm. All is normal so far.

The upright plate from RCR is drilled for a 7/16" bolt. The C4 hub supplied by RCR was also drilled out to 7/16" and used a 7/16" bolt with locknut to bolt the hub to the upright. The original C4 hubs came with a 10mm thread to attach to the C4 upright. So the Strano adaptor is designed for the C4 Corvette and has a 10mm threaded hole for mounting.

So now that I have the preamble/preramble out of the way, my plan now is to drill and tap the Strano adaptor to 7/16 coarse thread. All should be good.

I also have the C7 X Tracker 33 spline hubs for the rear. I plan to do what Ken did with a .190" spacer and a bushing to help center the hub. Instead of slotting the three mounting holes in the upright I plan to redrill the holes to 16mm at the new bolt circle dimension and make a sleeve to get back to 12mm.

 

[Howard Jones]

Are you saying to intend to open up the four 10 mm mount holes in the Strano adapter to 7/16 and re thread to course 7/16/ 14 ?

I would not do this for several reasons.

1. the adapter has been proven in it's current configuration I.E.10mm bolts.
2. re drilling to 7/16 will increase the hole diameter by more than 10%, thus reducing the material wall thickness of the adapter structure and its strength. (I don't know by how much, see #1)
3. course threads should not be used in high strength applications where steel is the parent material. Use fine threads in steel.

 

[Roger Reid]

Howard
Too late. Already drilled and tapped the 10mm holes to 7/16-14. The difference between 10mm (.394") and 7/16" (.438") is only .044". Not enough material wall thickness loss to worry about. The Strano adaptor is anodized aluminum so the 7/16 (14) coarse thread is good.
The problems didn't stop there. The (3rd gen) upright is so sculpted there is a 1/8" recess the original C4 hub fits into. The Strano has no relief for the recess. I'm not sure the Dulaney's hub adapter has this relief incorporated either. The Gen 3 sculpted upright needs the clearance machined into it or the adapter needs clearance machined into it. You can see in the attached pics the recess and the clearance I machined into the adapter. I also needed to shorten the head of 1 bolt attaching the adapter to the hub by 1/16".

 

[Roger Reid]

This is how much slop there is in the rear wheel bearings. The front wheels didn't have this slop, only the rear. Wondering if the slop goes away when you install and tighten the stub axle. Good reason to switch to the X Tracker hubs.

 

[Ken Roberts]

Yes, the C4 rear wheel bearing will have extra slop until the stubshaft is applied and tightened. Moving the car on the ground without the stubshaft will destroy the bearing.

Here is a couple of pictures of the Dulaney adapter. It is made from chromoly steel.
-The lip my pen points to in the first photo (left photo) shows that it is much smaller than the Strano adapters lip and will not interfere with the protrusion in the Gen3 front hub.
-The second picture shows my pen pointing to the small wings in the adapter for attaching a brake duct plate as shown.
-The third picture shows my pen pointing to the area that you machined off. It is much smaller on the Dulaney adapter and the front upright can be quickly modified with a aluminum burr on a die grinder.

 

[Ken Roberts]

Here is a photo of the OEM C6 Corvette jumper harness I'm using to connect the SKF 30 spline hub to the Racelogic wiring. It is part #15248662. The connector at the far end is PT 1757 or Standard Motors S-823. The harness is a robust piece.

 

[Roger Reid]

Ken. The Dulaney's hub adapter looks like a fine piece. Certainly worth the $500 each considering they are chrome molly steel. For purposes of this thread, the two different directions I could have gone were.
1. Make bushings for the upright spanning the difference between 10mm and 7/16" or drill and tap the adapter threads to 7/16-14 (.625" deep).
2. Machine the upright or the adapter for clearance.

 

[Mark]

Just to clarify the Dulaney adapters are $500 for the pair.

Ken, can you tell us what size bolts are used to attach to upright?

 

[Ken Roberts]

Just to clarify the Dulaney adapters are $500 for the pair.

Ken, can you tell us what size bolts are used to attach to upright?

The Dulaney adapters come with the required 4 bolts. They are ARP bolts M10.

They may no longer be available. I know he was taking his last order recently.

The left picture shows that the adapter is hub centric to the front upright. My pen is pointing to the precise fit between the two.

The right picture shows the adapter from the other side. It is a precise fit to the recess machined into the upright. The M10 bolts are just used for clamping force. They are fine to use.

 

[Howard Jones]

I think I have figured out why my driveshafts seam to have fitted without replacement. Here are two pictures. The second is the outboard face of my Gen 1 upright and the first is the outboard face of a later sculped upright. This face locates the bearing flange when mounted and thus positions the stubshaft in reference to it's CV flange. You can see that mine is flat ( it is even though the pedestal spot can't be seen here) in reference to the steel ball joint block where as the first one has a pedestal that the bearing flange sits on. This looks like the mystery difference we have come up with.

 

[Mesa]

“As the Wheel Turns” or in this case – wobbles.
I had upgraded my rear bearings to Timken level shortly before Howard had his rear wheel bearing/stub shaft failure. I was hoping I’d be good for a while, turns out “while” was less than 2000 miles. The wide wheels, heavy tires and HP proved too much for even one of the better OEM C4 solutions.

I now have the opportunity to implement our friend Howard’s solution for the (in my case) Gen I suspension uprights. I plan on ordering Driveshaft Shop C7 Stub axles (using the info on the closeup of Ken’s order receipt?) and GM Production level C7 bearing hubs. Everything else for my car will be minor machining as Howard lines out to finish.

What part number do I need for the C7 bearing set and where is the best (read quality US made part) place to buy them?
Thanks to all that contributed to these solutions.

 

[Ken Roberts]

Can't get much cheaper than this:

ACDELCO RW20153 Wheel Bearing & Hub | Shop Now at RockAuto

ACDELCO Brake & Wheel Hub Parts and More for Your Vehicle at Reliably Low Prices. Fast Online Catalog. DIY-Easy. Your Choice of Quality. Full Manufacturer Warranty.

www.rockauto.com

Keep in mind that you will need to make/install the spacers I mention (post#180 below) unless you have two piece rotors like Howard has. Howard machined his rotor hats instead. (post#179 below)

SLC Hubs/ race worthy

I did PM Ron. He said if Fran was OK with the spirit of this thread then it was OK with him. Another told me that he had spoken to Fran and in a nut shell he was OK with us trying to come up with several individual promising updates to the car in this area or something like that. In the end if...

www.gt40s.com

 

[Mesa]

I did see the Rock Auto Delco part offering, thanks for confirming it as an excellent price option. I have exactly the same rotor setup as Howard, so, good there as well.

Next call - The Drive Shaft Shop

 

[Brian Kissel]

I received the last set that Delaney made on his final run. He did mention that in the future he might do another run, but offered no time frame. I wanted to Thank Ken, and Howard for making me aware of this. This forum is a great resource.

Thanks again!!
Regards Brian

 

[Howard Jones]

Robert, you need two of these:

https://www.driveshaftshop.com/dome...el-flanges-to-fit-a-108mm-porsche-930-cv-2201

 

[Joel K]

“As the Wheel Turns” or in this case – wobbles.
I had upgraded my rear bearings to Timken level shortly before Howard had his rear wheel bearing/stub shaft failure. I was hoping I’d be good for a while, turns out “while” was less than 2000 miles. The wide wheels, heavy tires and HP proved too much for even one of the better OEM C4 solutions.

I now have the opportunity to implement our friend Howard’s solution for the (in my case) Gen I suspension uprights. I plan on ordering Driveshaft Shop C7 Stub axles (using the info on the closeup of Ken’s order receipt?) and GM Production level C7 bearing hubs. Everything else for my car will be minor machining as Howard lines out to finish.

What part number do I need for the C7 bearing set and where is the best (read quality US made part) place to buy them?
Thanks to all that contributed to these solutions.

Just curious, have you been tracking your car or has this been exclusively street use?

 

[Mesa]

95% low stress street or highway, 5% spirited curvy road action.
No track.

 

[Joel K]

95% low stress street or highway, 5% spirited curvy road action.
No track.

Thanks Mesa, I saw you put the extra wide tires on your SL-C I am wondering if that is more of the culprit than your Supercharged engine.

I’m putting in a stock Z06 which has 650HP/650TQ and was not originally planning on this upgrade since my car will be street only, but may change my mind as I get closer to that part of the build. Thanks to everyone helping to figure this modification out for the rest of us.

 

[Mesa]

Kind of excited. Before you is the DSS 33 spline C7 / 930 stubs and the Jones autograph model Gen-1 rear upright installation tools.
All's I need is the bearings and I'm off to the races. Looking forward to having this issue over and done with, never to be dealt with again.