Got new tires and wheels. Now I get an odd wiggle? (or at least the car does ;) )

[rherschberg]

Hey folks,
I just recently got a set of new tires and wheels for my 91 NSX. I had plain old stock 15/16's with pretty new tires. My new ones were off a 97 and in order to clear the calipers in the back the mechanic had to use some small spacers. The new ones are "17x7.5(offset36)(r)18x10(offset47) With Pirelli Super Sport P-7000. (f)p215/40/17zr (r)p275/35/18zr.

Since the wheels have been mounted, I notice an odd pull with the car at random times. It is not constant. It feels a bit like when your driving on the freeway and get on those grooves and your tread catches them wrong. It seems to pull to one side or the other or even slowly back and forth. Not a wiggle though. Seems to pull to some extent with the road and various terrain.

I'm wondering if:
1) I need to get a new alignment since I changed the tire and wheel sizing as well as offset.
2) If this is caused by the TCS and the new setup is setting it off.
3) The spacers are having an affect on the drive.
4) Something is wrong with the wheels/tires (ie mounted backwards (L/R switched), bad wear from the prior car...)
5) I'm just not used to the low profile feel of the road and need to suck it up cuz this is how a real mans car dives...

Does anyone have any thoughts?

 

[hlweyl]

Re: Got new tires and wheels. Now I get an odd wiggle? (or at least the car does )

I would get a good alignment and go from there. If you are still having problems, I would look at the spacers. I'm by no means an expert, but I have heard of others mentioning that the best type of spacers are "hubcentric" and not just a plain spacer over the lugs.

Good luck

 

[nsxtasy]

It could be any of several things.

1. Whenever you have new tires, the balancing of the tires is always the first thing to check. 'nuff said.

2. I agree with hlweyl that the spacers may be causing the problem. Wheels are fastened/supported by the lug nuts as well as the hub. The hub fits inside the center bore (that's the big hole in the middle of the wheel), and the five lug nuts bolt around the outside in a circle. When you use a spacer, this pushes the wheel out from the hub, and the center bore no longer fits on the hub. This is easy to see if you try putting one of your old wheels on with no spacers. This means that the centering is dependent on the five lug nuts fastening the wheel exactly right, and without the hub alignment, they can be off slightly, enough to create a vibration (and this can get worse over time). As hlweyl mentions, the "right" way to do this is to get the kind of hubcentric spacer that includes studs and a lip for the center bore, like this one from Dali Racing:

instead of the kind that is simply a flat plate like these from R&S:

Incidentally, the same thing happens when some folks use wheels that were not designed for the car, so that the center bore is larger than the hub. The cure for that case is "hubcentric rings", which accomplish the same thing (fitting the center bore onto the hub) by the use of a ring to narrow the center bore opening.

3. As hlweyl notes, it could also be the alignment. However, if it is only doing this with the new wheels/tires/spacers and not the old wheels/tires, then it is not the alignment.

It should NOT be due to TCS; these tire sizes should not create any problems for the TCS on your '91.

 

[USpeed757]

Re: Got new tires and wheels. Now I get an odd wiggle? (or at least the car does )

I had a similar pull like that in my old Supra when I got some new wheels and tires put on it. I just had the car aligned before I installed the new wheels, so that wasn't it. Turns out the tire place had put only 5 lbs of air in one of my rear tires. The profile was so low that it still looked ok, but the car pulled real bad. I added the proper amount of air and the problem was gone. Just a thought, might want to give that a check also.

 

[nsxtasy]

Good idea. Always start with the things that are the easiest to fix as well as the most likely...

 

[Vegas Boy]

Re: Got new tires and wheels. Now I get an odd wiggle? (or at least the car does )

I would bet it's the spacers as well. I have had this prob with other setups, and if the
right spacers to fit the hub are not used, they will wobble. It does not take much to throw the overall balance off at highway speeds. Wheels that are advertised as somewhat universal in fittment are "lug centric" which means they will fit the lug pattern, but has was said above you need them to be hub centric or use adapaters.

 

[rherschberg]

Re: Got new tires and wheels. Now I get an odd wiggle? (or at least the car does )

Well, I went to a good tire shop today and took the mechanic for a ride (normally the otehr way around, ). He found that one issue I have is that my left front tire has a large flattened out spot on it. It almost looks like the wheel was locked up in that one spot! It is a little strange since I don't see that sort of wear on any of the other tires. It is also on just one side of the tread. the other side is fine.

Anyway, they are ordering me a new tire and we will be sending the tire back to pirelli to see if it is a defect (maybe covered by warantee? ). the tire guy thought it might be a separation in the tread that is causeing the odd wear pattern. Just the luck though. The tire is discontinued so they are looking all over the country to find the same tire so I don't have to buy 2!

While I was there, I had him pull one of the front and one of the read wheels. The front has a ring on it to make the wheels hubcentric design fit my hub. He validated the fit and its good when using the ring. When they replace the tire, I'll have him check the other side just in case .

On the back, when he pulled the wheel, we saw the spacer. It is as you mention, a flat spacer. It is really thin though. maybe 1/8 inch? I asked and he said the hub is barely touching the hubcentric set on the wheel, but definutely making contact. Not ideal, but still a working system. He thought since it was soo thin and it does actually touch, that that was probably not the issue.

Do they make really thin spacers that are hubcentric? I only need about 1/8". Also, I would be curious if there is any way other than a spacer to stop the brake caliper from rubbing. I seem to remember someone saying they sanded down the caliper, but that seems scarry to me. Anyone got an idea?

Thanks,
Rick

 

[willabeest]

would not the TCL light go on if it was the TCS causing the problem?

Hey folks,
I just recently got a set of new tires and wheels for my 91 NSX. I had plain old stock 15/16's with pretty new tires. My new ones were off a 97 and in order to clear the calipers in the back the mechanic had to use some small spacers. The new ones are "17x7.5(offset36)(r)18x10(offset47) With Pirelli Super Sport P-7000. (f)p215/40/17zr (r)p275/35/18zr.

Since the wheels have been mounted, I notice an odd pull with the car at random times. It is not constant. It feels a bit like when your driving on the freeway and get on those grooves and your tread catches them wrong. It seems to pull to one side or the other or even slowly back and forth. Not a wiggle though. Seems to pull to some extent with the road and various terrain.

I'm wondering if:
1) I need to get a new alignment since I changed the tire and wheel sizing as well as offset.
2) If this is caused by the TCS and the new setup is setting it off.
3) The spacers are having an affect on the drive.
4) Something is wrong with the wheels/tires (ie mounted backwards (L/R switched), bad wear from the prior car...)
5) I'm just not used to the low profile feel of the road and need to suck it up cuz this is how a real mans car dives...

Does anyone have any thoughts?

 

[docjohn]

Re: Got new tires and wheels. Now I get an odd wiggle? (or at least the car does )

Do they make really thin spacers that are hubcentric? I only need about 1/8". Also, I would be curious if there is any way other than a spacer to stop the brake caliper from rubbing. I seem to remember someone saying they sanded down the caliper, but that seems scarry to me. Anyone got an idea? I have used 5mm spacers for the rear, one set was a generic pep boys and the other from HR which is better made.As you described this pushes the center ring of the wheel away from the center bore of the hub and they barely make contact.I have had no problems with either.

 

[nsxtasy]

Do they make really thin spacers that are hubcentric?

No, sorry.