Hub-centric 5 lug Options

[gms]

mount up on lathe


Stock version on left

[gms]

Stock version on left


Mmmm hub-centric!

[Eric_Shea]

Took me a while. I was looking for the lathe marks and missed the obvious end of the shaft.

This has tremendous potential. Have you checked rotor offsets? 944?

The 911 rotor will need to be spaced 10mm out and the 914-6 will need 5mm BUT... the 944 rotors may just be the ticket!!

AND... it pulls the offset in another 1/4" plus. Right where we need it!

(Eric exits stage left and scrambles for parts...)

[SirAndy]

I like that!

I had a set of those 944s at some point, probably lost in space by now (or at McMark's shop).
(IMG:style_emoticons/default/idea.gif)

[Eric_Shea]

I had a set of those 944s at some point

Those are probably a different offset altogether. It would be worth measuring though. (IMG:style_emoticons/default/idea.gif)

[TravisNeff]

So 5mm off the backside of the wheel bearing side? Is this so that you don't have to use a spacer, or is there another added benefit.

[CptTripps]

This is timely. I think I'm fighting what this fixes...

I put my 5-lug rears on yesterday and they're just a LITTLE lose. I was thinking I needed a spacer, but taking 5mm off the back might be easier. I can have a machine shop take that off.


https://www.youtube.com/watch?v=Lw9jVBF2lOQ

[Luke M]

With the later 5 lug hubs you need to put a spacer between the hub and bearing.
PMS sells the spacers for the later hubs.

[TravisNeff]

The worry I have with the spacer is that it pushes out the hub 5mm, which reduces tire clearance (I have my fenders pulled a little bit, and don't want to pull them more running 7's)

[Eric_Shea]

Doug, you need the hub shaft spacer that Luke suggests. Late model hubs are made for the later 911 bearings which are the same ID size but "thicker" than the early bearings used on 914's and early 911's.

Travis, the spacer doesn't push this hub out any further. The extra 5mm for the later hub came off the backside of the hub. This effectively makes the shaft longer to fit the new bearing, which is what Glenn machined off (the "end" of the shaft). By doing it this way, Glenn has moved the hub face "inward" giving you more tire clearance. If you put the spacer on the hub-centric hub it makes it identical to the early hub.

Again, by machining the end off, Glenn will be moving the face inward and the hub shaft will now fit the early bearing. I'd be willing to bet 944 rotors are the ticket here.

[jaxdream]

This is timely. I think I'm fighting what this fixes...

I put my 5-lug rears on yesterday and they're just a LITTLE lose. I was thinking I needed a spacer, but taking 5mm off the back might be easier. I can have a machine shop take that off.


https://www.youtube.com/watch?v=Lw9jVBF2lOQ

If you pull those hubs you might stand a chance of destroying the wheel bearings . to tighten up put a spacer ( possibly 4-5mm ) on the backside of the stub up against the inner bearing race between the flange of the stub where the cv mounts, other wise source another set of wheel bearings just in case . YMMV.......

Jack

[CptTripps]

If you pull those hubs you might stand a chance of destroying the wheel bearings . to tighten up put a spacer ( possibly 4-5mm ) on the backside of the stub up against the inner bearing race between the flange of the stub where the cv mounts, other wise source another set of wheel bearings just in case . YMMV.......

The hubs actually come out relatively easy. (Not just "pull out" but I can get them in/out without the press.)

I've already called PMS about 2 spacers and will see if I can get them here quickly.

[mskala]

Took me a while to realize this is about modifying a later-model part.

But what is the point of this? Trying to gain 5mm clearance at the expense
of modifying brake mounting?

[SirAndy]

But what is the point of this?

The point is to have hub centric hubs so you don't have to rely on the wheel studs to center your wheel ...
(IMG:style_emoticons/default/shades.gif)

[worn]

Took me a while. I was looking for the lathe marks and missed the obvious end of the shaft.

This has tremendous potential. Have you checked rotor offsets? 944?

The 911 rotor will need to be spaced 10mm out and the 914-6 will need 5mm BUT... the 944 rotors may just be the ticket!!

AND... it pulls the offset in another 1/4" plus. Right where we need it!

(Eric exits stage left and scrambles for parts...)

Is the difference in shaft lengths the reason I had to offset my M calipers when I used a 911 stub? I should have done more reading before assembly.

[mskala]

But what is the point of this?

The point is to have hub centric hubs so you don't have to rely on the wheel studs to center your wheel ...
(IMG:style_emoticons/default/shades.gif)

However, you already have the studs there, which will center the wheel. I don't see
any mod to the part to make it threaded for using wheel bolts.

(IMG:style_emoticons/default/confused24.gif)

[SirAndy]

However, you already have the studs there, which will center the wheel. I don't see
any mod to the part to make it threaded for using wheel bolts.

(IMG:style_emoticons/default/confused24.gif)
You lost me there ... Wheel bolts????


The point is that with even with 5 studs, you're relying on those to center your wheels when tightened and there is a chance that you'll torque down your wheels slightly off center and create a wheel imbalance.

The inner 3 piece ring on the new hub shown in this thread makes sure that the wheel is completely centered. Hub centric they call them for that reason.
That allows for proper wheel fitment every time with now chance of getting them off center.
(IMG:style_emoticons/default/smile.gif)

[mskala]

However, you already have the studs there, which will center the wheel. I don't see
any mod to the part to make it threaded for using wheel bolts.

(IMG:style_emoticons/default/confused24.gif)
You lost me there ... Wheel bolts????


The point is that with even with 5 studs, you're relying on those to center your wheels when tightened and there is a chance that you'll torque down your wheels slightly off center and create a wheel imbalance.

The inner 3 piece ring on the new hub shown in this thread makes sure that the wheel is completely centered. Hub centric they call them for that reason.
That allows for proper wheel fitment every time with now chance of getting them off center.
(IMG:style_emoticons/default/smile.gif)

The lug nuts are spherical and will center to the studs. So what you're saying is
that Porsche is incapable of producing a hub with properly aligned studs, but it is
totally capable of producing a perfectly aligned ring for centering.

[mskala]

lug nut


wheel bolt

[r_towle]

However, you already have the studs there, which will center the wheel. I don't see
any mod to the part to make it threaded for using wheel bolts.

(IMG:style_emoticons/default/confused24.gif)
You lost me there ... Wheel bolts????


The point is that with even with 5 studs, you're relying on those to center your wheels when tightened and there is a chance that you'll torque down your wheels slightly off center and create a wheel imbalance.

The inner 3 piece ring on the new hub shown in this thread makes sure that the wheel is completely centered. Hub centric they call them for that reason.
That allows for proper wheel fitment every time with now chance of getting them off center.
(IMG:style_emoticons/default/smile.gif)

The lug nuts are spherical and will center to the studs. So what you're saying is
that Porsche is incapable of producing a hub with properly aligned studs, but it is
totally capable of producing a perfectly aligned ring for centering.

It is quite possible to torque down a wheel offcenter.
Aluminum wheels, steel (bolts or nuts) can grab the wheel in such a way that you can honestly mount them off center, and they bounce like crazy.

I learned all about this with my BMW....with stock wheels....
I jumped up to 7 series which had a center hole 2mm larger....wheel bounced all over the place.

I had to get special adapters, little plastic sleeves that fit over the hub....fixed it.

I mounted those wheels probably 20 times trying to figure this out.
Had them balanced at least 5 times, at three different shops.

Ended up being a 4 dollar little sleeve, all was well.

rich