blau928

Ok Imre, I mentioned it earlier, but will do it again for you just to clarify...
The newly released centerlock option on the new Porsche cars with DOT certification are ALUMINUM. Same as the current front hub is now on your 928.

The RACE parts as used by PORSCHE MOTORSPORTS in FIA sanctioned events are STEEL. The parts I want to make are STEEL.

Although I will make the parts out of aerospace grade hardened steel, I will not be getting DOT certification on the parts, as it costs too much for 5-10 sets as indicated by interest so far. So if anyone wants to use this stuff, it will be for off road use only. It is a race part.

However, it will be the engineered to the same hardness etc. as the RACE parts used by PORSCHE MOTORSPORTS. That is good enough for me to use on my personal vehicle.

If I can make it clearer than this, please let me know...!

Lizard928

The weakest link will always be the factory hub, or the wheel itself.

This larger spindle is easy to make stronger than that piece, out of both aluminum, or steel as the hub is cast. And billet will be stronger.

Imo000

Don't go right away on the defensive and blindly argue only one side or you'll miss the big picture.
If you never properly tested a product, you have no real way of knowing if the engineering and/or the manufacturing process is sound. You are assuming that the same desing that Porsche uses on a 911 will be safe on a 928. Changing it to sell them for off-road use only is a wise choice but, will that still make you liable if something horribly goes wrong and turns out it's a design flaw? You have to look at both sides of the coin and be open minded when it comes to manufacturing a product, that can adversly effect the safety aspect of other people's cars. This is basic risk management.

Have you heard the saying: "If you fail to plan, you plan to fail" ?

blau928

Hi Imre,

Thanks for the concern. I appreciate it. I am not trying to be defensive at all. I was pointing out to you again, that I mentioned several times before, the material will most likely be 300M, a silicon vanadium alloy, which is used in aircraft landing gear. In addition, maybe what I should have also mentioned, is that the hardness, bend, and shear strength analysis is being done by a test lab, and a materials engineer for comparison to the rear setup.

There is no way that this part will be the weak link in the front wheel assembley. It is physically impossible due to the design of the setup, and the fact that the wheel hub is aluminum riding on a steel bearing race, and the wheel itself is aluminum, or in my case, magnesium. If anything fails, it will be like Colin mentioned, the wheel or the hub will be it.

The rear, as I mentioned is already developed by a racing supplier, and the parts are also tested for bend, shear, and hardness.

You mentioned the comment about design for the 911 not being the same as for the 928 in skepticism without actually knowing if certiain parts are the same. Well, I have a bit of news, as many are exactly the same. For example, the rear wheel bearings are exactly the same.

As for risk management, I have quite a lot of experience in that field, as I do risk and compliance management for publicly traded companies on the stock exchange. The same principles apply, you are correct. Prior to applying a solution, one must understand the risk. To do that, one needs to understand the situation, and the facts, and separate that from hearsay and opinion......

Thanks for the concern, but there is more engineering going into everything I make than is revealed by me, or known to all but very few people who are actually involved.

Again, I am not trying to be defensive at all, but there are details I think from your writing that you are either not understanding, or overlooking. Then again, maybe it's just me that's not getting it. In which case, I apologize.

Like I said before, and will say again, I want anyone interested to comment based on the facts, not just opinion.

There is actually little failure to plan here, as I have said, it's not for everyone, and will be for off road use only and it will not be DOT certified as clearly stated in post #6 as a direct reply to your prior question. No changing here, same as originally stated.

Thanks again, have a great day..!

Imo000

Fair enough.

ew928

Dumb question.

Do the centerlock wheels use pins on the hubface to connect with the wheel?
Or is wheel just driven by the hub with friction.


Been a long time since I've been to the track and seen a racing wheel setup.

blau928

EW,

It is not a dumb question if you don't know..

Yes, there are 5 drive pins on the hub of this specific setup that go into counterbores in the wheel that are Porsche spec, 5 X 130, that allow the wheel to drive the hub if an undriven wheel, or the hub to drive the wheel if it is a driven wheel. They are the same size as current wheel studs on the regular hubs.

In addition, the central locking nut provides a clamping force on the pressure disc to secure the wheel to the hub and spindle.


Hope that helps,

Ducman82

so how goes this project?

inactiveuser1

Richard,
Looks like it will be a nice setup.Will it save any reciprocating weight?I can see it being worth it for racing if the setup takes weight out of the car especially if it does save weight on the rear axles to save horsepower.
I haven't seen the thread of the supercharger in a long time how far are you on that?

andy-gts

this is sooo cool. I had a mgb with center lock wheels and they were so easy to use, were unique and just made sense to one of that inclination....any price yet as you can run center locks or 5 bolt up wheels with his system....

Ducman82

any updates?

Mark Anderson

a bit

blau928

Hi Ducman,

Since my shoulder injury, all the car stuff is on hold. I am making progress on recovery, but, the centerlock front hub/spindles are at the backburner until I finsh the SC setup. (My goal is to still finish the SC setup by June for the Porsche Parade in Monterey.)

The rear hubs are essentially bolt on pieces, but require the pin drives and centerlock spindles, all of which I have.

I only have to make the fronts..

Thanks,

Maltese Falcon

Richard, we are using these Forgeline brand center locks and same brand wheels on our POC mid engined racer.
The 928 will look HOT with CL's.
Marty

MN

Porsche now offers carbon wheels as an option for the 911 Turbo S. Are of course centerlocking.

Did you ever finish your project and offer a centerlock conversion for the 928?

Thanks.