Thunderbird Hub bore sizes. Concentric rings.....

ricardoa1

Registered User
I have been trying to get to the bottom of this problem, Brad at the Custom Wheel Shop, has 63.90mm ID concentric rings for his wheels. But test fitting them on my car I noticed that they are actually too big.



Innacurate information deleted.
 
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If they will be custom made your best bet will be to measure your parts. I went with some quoted figures on this site to have a machinist friend make some rings for me, they ended fitting a bit sloppy. When he made them again to my measurements they turned out perfect. I don't have any numbers off hand but they were different enough to matter.

Bob
 
I'm sure I could make you a pair in Delrin if you give me all of the dimensions that you want.....
 
I just took some quick measurements on a late rear hub, and came up with a minimum dimension closer to 63.25mm. I also noticed a step near the face of the hub.

I have MN-12 rear hubs and Cobra rotors and wheels around the shop, so I could certainly make a pair from Delrin, but they'd have to be somewhere around $60 shipped to make it worth my time.
 
I just took some quick measurements on a late rear hub, and came up with a minimum dimension closer to 63.25mm. I also noticed a step near the face of the hub.

I have MN-12 rear hubs and Cobra rotors and wheels around the shop, so I could certainly make a pair from Delrin, but they'd have to be somewhere around $60 shipped to make it worth my time.

The step is for the rotor I belive and its slighty bigger in measurements. I have a late hub also since I redrilled a loose one and not the one that came originally in my car.

What are your thoughts on it being made out of Delrin, usually they make them out of Polycarbonate or Alum and sometimes Stainless. Im not sure if Delring can witstand the heat cycles or be stiff enough to locate the wheel. No argument just curious.
 
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Delrin is plenty stiff, all the ones I've ever seen were just plastic.
 
I deleted all innacurate information above.

I found my old 94 hubs and 90 Front hubs. They all measure the same where it meets the rim. The rotor locating step is different though and much larger on the early hubs. So all MN12 wheels have the same hub bore size at the wheel.

Then rings supplied by Brads shop are too big, Not sure if it was a manufacturing problem or what. I found a set of old centric rings that I used when I had superior scoundrels. And those fit the T-bird hubs near perfect, but the superior wheels were much larger around the hub bore then the Mustang cobra R I have. I could maybe send you these old rings to you Doug to maybe machine them to the smaller 70.8mm Mustang size, not sure how much you would charge for that.

I think there is evidence that for some reason some manufacturers belive we have 63.9MM hubs, As you can see they advertise that is our size.
http://www.ezaccessory.com/Hub_Centric_Ring_O_D_73_I_D_63_9_p/hcr106-4.htm

But like Doug found out those measurements are not even close, 63.36MM Hub diameter is closer to what we have Prestige Wheels carries the 63.36MM ID but dont have a matching 70.8 OD :(
http://www.prestigewheel.com/mainHubRing.htm
 
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I deleted all innacurate information above.

I found my old 94 hubs and 90 Front hubs. They all measure the same where it meets the rim. The rotor locating step is different though and much larger on the early hubs. So all MN12 wheels have the same hub bore size at the wheel.

Then rings supplied by Brads shop are too big, Not sure if it was a manufacturing problem or what. I found a set of old centric rings that I used when I had superior scoundrels. And those fit the T-bird hubs near perfect, but the superior wheels were much larger around the hub bore then the Mustang cobra R I have. I could maybe send you these old rings to you Doug to maybe machine them to the smaller 70.8mm Mustang size, not sure how much you would charge for that.

I think there is evidence that for some reason some manufacturers belive we have 63.9MM hubs, As you can see they advertise that is our size.
http://www.ezaccessory.com/Hub_Centric_Ring_O_D_73_I_D_63_9_p/hcr106-4.htm

But like Doug found out those measurements are not even close, 63.36MM Hub diameter is closer to what we have Prestige Wheels carries the 63.36MM ID but dont have a matching 70.8 OD :(
http://www.prestigewheel.com/mainHubRing.htm

Prestige states on their site that they'll do custom rings (with an 800 number, no less), have you checked with them?

What are your old rings made out of?

Are you looking for rings just for the wheels? What about centering the rotors?

Didn't you say earlier that you've already done the bolt circle swap on the front? Why not just do the rear as well? In the long run it seems the simpler solution.
 
The old rings are Polycarbonate plastic too.
I only need rings to center the wheels, I got the rotor issue figured out Im using a late set of rotors for the rear that matches to the hub.

I had the rear hubs redrilled so I already have the mustang pattern, if I do mustang hubs in the rears then ill have to spend money on relocating brackets and upping to the cobra rotors, Then the brakes will be slightly disproportional. Im using the stock calipers up front with stock sized mustang rotors.
 
Cant you just use factory mustang rear rotors with the swap??

Or redrt
The old rings are Polycarbonate plastic too.
I only need rings to center the wheels, I got the rotor issue figured out Im using a late set of rotors for the rear that matches to the hub.

I had the rear hubs redrilled so I already have the mustang pattern, if I do mustang hubs in the rears then ill have to spend money on relocating brackets and upping to the cobra rotors, Then the brakes will be slightly disproportional. Im using the stock calipers up front with stock sized mustang rotors.
 
Cant you just use factory mustang rear rotors with the swap??

Or redrt

Id have to spend money on new hubs and redrilling the stock rotors if I choose the other method. Mustang rotors dont fit in the rear only the cobra 11" rotors fit, for those you need relocating brackets ect.

I did not think before that centric rings were going to be a huge issue, but the fact that even these sloopy ones that I got made made the vibes a little better I am hoping that with the perfect size ones will make it go away. Wishful thinking since I know both my cars hate me one way or another.
 
The old rings are Polycarbonate plastic too.
I only need rings to center the wheels, I got the rotor issue figured out Im using a late set of rotors for the rear that matches to the hub.

I had the rear hubs redrilled so I already have the mustang pattern, if I do mustang hubs in the rears then ill have to spend money on relocating brackets and upping to the cobra rotors, Then the brakes will be slightly disproportional. Im using the stock calipers up front with stock sized mustang rotors.

If you want me to reduce the size of your old rings to fit inside Cobra R's, just send them to me.
 
Can someone measure their stock wheel hub bore? I want to see how much clearence Ford gives between the wheel and the hub..:confused:
 
No PM or nothin...Nice

Do you exp. vibration using the rings?? They are intended only as an alignment tool. If you dont like/want them return them.

I think Polycarbon is most common because if the wheel comes loose for whatever reason you dont have a piece of Metal in there chaffing or fretting your wheel. I actually had some rear studs break off and the wheel came loose. It should have destroyed the wheel, but the ring kept the wheel from hitting the hub and left zero damage to the wheel lug pockets and hub-bore, etc...Needless to say I was pretty impressed already expecting the wheel to need replaced.

63.90 was always documented as the standard and I never questioned it. Regardless there are ALOT of people, including myself running them with no issues. The next ones I have built will be machined to 63.50mm.

Brad
 
No PM or nothin...Nice

Do you exp. vibration using the rings?? They are intended only as an alignment tool. If you dont like/want them return them.

I think Polycarbon is most common because if the wheel comes loose for whatever reason you dont have a piece of Metal in there chaffing or fretting your wheel. I actually had some rear studs break off and the wheel came loose. It should have destroyed the wheel, but the ring kept the wheel from hitting the hub and left zero damage to the wheel lug pockets and hub-bore, etc...Needless to say I was pretty impressed already expecting the wheel to need replaced.

63.90 was always documented as the standard and I never questioned it. Regardless there are ALOT of people, including myself running them with no issues. The next ones I have built will be machined to 63.50mm.

Brad

Brad I called the shop and spoke to someone there, he was unsure what I was telling him was true or not. The sizes you have in stock will work but they are too loose for my taste. I took it upon myself to figure the problem out. I asked your shop collegue to find out what he can get in the smaller size, still he has not gotten back to me. Im having Doug machine down the OD on the old set I had when I had Superior Scoundrels. I do intend to return this set as I am not happy with them. No harm done on your part, Im mostly surprised that after all the years the numbers hovering around have not been corrected.
 
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