Info on weight of reproduction QV wheels:

the real QV wheels are a few pounds lighter. this was discussed in an ancient thread long ago. ( not that it matters, nor am i implying anyone search for it )
anyway, i think its great that you took the time to measure them and share it with us, i am surprised how close the weights are. i doubt the weight would really affect a street driven car much either way. the FEEL and the handling should be much improved with the 16's.

 

Much improved!!!

 

Birdman,

As you well know rotating mass is an interesting thing as it also depends on where the mass is located. When we hook up this spring/summer i'd be delighted iof you want to have a go with the 308 here and make your own decision. Lighter IS better and i do notice more agility/etc overall, but then again lighter shocks/springs, lowering, light rims, etc... So perhaps the comparison between cars will be skewed a bit, though want you to feel for yourself the difference my friend..

 

Odd, I have the same wheels and they roll as smooth as glass. '78 GTS

 

I was aware of the problem and of the rings but I was questioning why some of us have the vibration problem and some don't. Did they change the hubs on some of these 308's or is the machining of the wheel hub inconsistant?

Would it have anything to do with the overall condition of the front suspension of each car?

Makes one wonder.

 

I'm having some trouble seeing why, if the wheel is a slight bit off-center when first applied up to the hub, any centering irregularities would not simply be worked out as one progressively tightens the 5 bolts in the required "star" tightening pattern?

Recall that these bolts have tapered shoulders, so they will, combined, serve to self-center the wheel as they are tightened, irrespective of any 'slop' that might initially be present due to a too-large center hub hole in the wheel.

I instead tend to think you have more of a bad conventional tire balancing job rather than a fault with the wheel. For some reason I only seem to have good success with about 2/3rds of the balancing jobs done on my various tires over many years ... justification in my eyes to spend a bit more money at the first and buy their "lifetime" balancing warranty on their work.

 

I had a vibration and it disappeared instantly with the addition of the centering rings.

 

My rings were very snug but did not require any machining. I put antiseize on them and 'pressed' the ring / wheel/ hub assembly together by carefully tightening the wheel bolts in an even manner. When I removed the wheel for my suspension re-build, it came off easily and the rings stayed in the wheels. I too blamed everything and even had Michelin give me 4 new tires because the ones I bought were not as round 'as they could have been'. Boy did I feel like a jackass when I bolted on the rings and the problem was totally gone.

 

Guys - I am -not- challenging your past experiences in any way. If the centering rims have worked well for you, then that's wonderful.

It is just that this "cure" seems illogical to me. The very act of tighteneing the tapered shoulder lug bolts serve the purpose of centering the wheel on the hub, making the use of any centering ring irrelevent.

If the bolts instead all had straight shoulders, then absolutely - there would be the possibility of the wheel going onto the hub off-center a bit, since tightening these straight bolts would do nothing to center the rim. But that's not the case here at all.

Think of this question in another way - ever watch a NASCAR (or similar series) pit stop on TV? Those guys fling those new wheels / tires on to the car, and the fact that they go on so easily leads me to conclude that the center hubs must be a bit oversized (if they fit really snug on the hubs, then one would expect to see the tire man have to fiddle with the new wheel to get it to seat precisely on the hub). Then, they ram those lug nuts (which are tapered) home with a high powered impact wrench and send the driver out again to run at 200 mph. One does not hear of consistant tire balance problems in racing like this, and I attribute this to their use of tapered lug bolts and nuts along with a super critical wheel / tire balancing job.

So, based upon the above, the use of a centering ring does not seem to me to be able to be the key player here in solving your tire / wheel balancing problems. Much more likely in my mind is a bad balancing job, due either to an inexperienced balance machine operator, or else the balancer being set to a very course tolerance level (which happens more often than you might think - otherwise, tire stores would spend hours trying to micro-balance each and every new tire).

Again - if the use of the hub ring has worked for you in the past, then I am certainly -not- trying to dispute your success. But I still think that there's more at work here than this!

Other thoughts? Cheers - DM

 

Dave I agree that the vibration goes totally against the sound reasoning that the bolt tapers will center the wheel. I too believed this and tracked every other option down. I guess the simple answer here is that the rings work despite the centering effects of the bolts.

 

The centering problem has to be with the holes or bolts.
Here's a few hypotheses:
1) The hole pattern in the wheels may sometimes be machined slightly off-center.The ring ensures centering & the bolt tapers contact the outside of the holes, possibly not fully seating in the holes.
2) The wheel's taper is at a slightly larger angle than the bolt head taper. Thus the bolts can tighten down with the wheel slightly off-center.
3) The bolts were made with the wrong/different angle, so the effect is the same as 2).

Be interesting to find out what happens if you swapped front & rear wheels. Do the rear ones also have the centering problem & it's being masked by the more rigid rear hubs?

 

Hello all! I am new to this site, but found it searching the net for some information on the following question; I have a 328 GTS -88 with ABS and hence the ABS style wheels. However do I find the non ABS wheels moore attractive, and would therefor like to change. Can this be done, and if yes, how?

 

(E) all of the above.

By jove, I think he's got it!

 

(E) wouldn't surprise me...

I think once we get the centering rings installed we'll be able to figure out the answer.

We'll put a smear of prussian blue on the bolt tapers & see where they mark up the wheels. Maybe do a set of before & after marks.

 

Great to hear that the vibration is gone. It's amazing how a tiny part can make such a huge difference.

 

Was there any additional charge for the rings?