Look at the factory lugs. they have an angled flange when the nut meets the wheel. This angled flange is designed to center the lug hole on the wheel with the stud. Any wheel designed as to fit a mustang has the same recess in the hole for the lugs. the lug and stud are what hold the wheel in place. Whether the wheel recess for the hub fits snuggly or loosely does not matter because the lugs themselves would have to allow movement for the wheel to wobble or shake. Trust me, hubcentric rings have no purpose in mustang applications. other cars yeah, mustangs no.

 

Quick update ... still have not gotten my hub centric rings off eBay, but had the front two wheels rebalanced this AM at Discount Tire. All is well ... one side was off 3 oz and the other 1/2 oz. It now drives straight and has no vibrations.

I wasn't too awful pleased with the attitude of the mgr at Discount Tire though ... told me the Nitto 555's are at the low end of the performance tire market and that is why I had the problem to begin with. Of course it goes without saying that they don't sell Nitto there.

 

hahahaha, nitto's are not on the low end. he's just trying to come up with an excuse of why they didn't find them off balance in the first place. 3oz is quite a bit off on tire balancing.

 

Actually they were not originally balanced at Discount Tire. I'm sure it was this salespersons way of thanking me for buying them somewhere else ... yet they know they couldn't get the wheels for me anyway.
I bought the wheels/tires from Extreme Customs in WI. Tyler is a great guy there, but they obviously need to pay more attention to getting the proper balancing.

 

That issue sounds familiar !

I have some 18" Shelby Razors with Nitto 555 and when I first got my wheels and tire combo everything was fine, even though the guys from Ameican racing told me the the ring were not required but wouldn't hurt. They just basically helping centering the wheel at instalation because the lugs will be responsible to center everything.

After a couple of days I stated to feel a vibration at 70mph, so I went back to check the balance and they found that 3 wheels were slightly out of balance. They re-balanced them and after it was worst, so I assume their equipment wa not calibrated so went to another shop that was performing Road Force balancing and again still had a vibration.

Took the ring off no change, so I tried rotating the tires around to find the 2 tires were worst than others when installed in the front, so I convinced the store that sold me the tires to replace them and rebalanced the whole 4 wheels again.

Since then I still have a little intermitent shake at 70mph but not as bad as before.

So yes the tires do seem to be responsible for the shake as they were able to improve by changing the tires but still have other avenues to explore.

First I would like to change the lug nuts, I have use very small "tuner" lugs and as they are smaller in diameter to fit inside the wheel.

Next step if that does not work would be to have the wheel balanced using lug finger adapter rather than the standard center conical attachment, since my wheels are lug centrics it would balance them using the same mouting points than when they are installed on the car.

Any other suggestions ?