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Old 03-29-2005, 06:54 PM
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Talking Info on weight of reproduction QV wheels:

Hi All,
I put tires on my new Superformance QV replicas today and put them on the car. MAN, they look sharp! I can hardly wait for some decent weather to test drive. Maybe tomorrow. Anyway, while I had the wheels off, I decided to do a comparison of the weight, compared to the 14"x7.5 campys that were on the car.

I was running with 215/60 tires on the 14" wheels, but the spare still had one of those big ol' 205/70 XWX donuts, so I can compare several wheel weight combinations:

I did this with a bathroom scale, so the absolute numbers are not accurate, but they are probably good enough for comparison purposes:

14"x7.5" Campy (Magnesium) wheel with 215/60 tire: 34 pounds
14"x7.5" Campy (Magnesium) wheel with Michelin XWX 205/70 tire: 41 pounds

16"x7" QV Superformance (aluminum) wheel with 205/55 tire: 41 pounds
16"x8" QV Superformance (aluminum) wheel with 225/50 tire: 48 pounds

I would love to compare these weights to a magnesium QV wheel.

So, if you are like me, swapping out the magnesium 14" wheels for 16" repro QV wheels, the front ones are the same weight as a stock 14" wheel with the OEM tire. The rears are going to be about 7 pounds heavier.

I would assume based on this that real magnesium 16" QV wheels would actually be lighter than the 14" OEM wheel/tire in front, and about the same as OEM wheel/tire in the back.

Birdman
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Old 03-29-2005, 07:08 PM
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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.
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Old 03-29-2005, 08:07 PM
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Much improved!!!
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Old 03-30-2005, 07:38 AM
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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..
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Old 03-30-2005, 06:16 PM
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Hi Steven,
Thanks for the offer. I seriously doubt that I would be able to tell the difference between the wheels with all the other differences between our cars. Between your brakes/suspension/wheels and mine (basically stock) I'm sure my car would feel like Fred Flintstone's car to you! (Ah, but that carb induction sound!)

BTW, I finally got it out on the highway today. The 16" wheels make the car much better to drive. The decent rubber actually sticks to the road. I did a few on-ramps at speeds that would've resulted in me sliding off the road with the old tires. Fun! The steering is more precise. The ride is a bit harder too. However, one of my front wheels has the dreaded Superformance "vibration" and I need the hubcentric rings to center them properly. Hopefully Superformance can get them to me ASAP. The season is nearly upon us!

Birdman
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Old 03-30-2005, 11:11 PM
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Odd, I have the same wheels and they roll as smooth as glass. '78 GTS
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Old 03-31-2005, 10:10 AM
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Hey Spasso,
This is a known issue with these wheels--fronts only. Depending on the hub diameter and the machining of the wheel, sometimes you need a small ring that goes on the hub before the wheel to be sure the wheel is centered in on the hub. This has been documented here in the past, and not everyone has the problem. I e-mailed Superformance about it and they e-mailed back that the hubcentric rings have been airmailed today. Fast!

The only thing that bothers me about this is that T. Rutlands, which is now the U.S. distributor for these wheels, had never heard of the issue. They had no idea that there even WAS such a ring, nevermind knowing that they should have been supplied with the wheels! I had to go to the manufacturer for them. Had it not been for Fchat, I would never have known about this issue. It would have taken me who knows how many trips to the wheel place to have the wheels balanced 20 times before I figured out that it's not the wheel balancing!

Birdman
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Old 03-31-2005, 04:27 PM
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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.
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Old 04-01-2005, 12:08 PM
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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.
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Old 04-01-2005, 12:20 PM
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I had a vibration and it disappeared instantly with the addition of the centering rings.
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Old 04-01-2005, 12:56 PM
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Dave,
This is a known issue with these wheels. It is not the balancing. I had a very careful balance job done where they actually measure the tires and wheels, then mount the tire in the best orientation to minimize the amount of weight needed. Then they balance the whole thing together. This balance job for all 4 wheels took about 90 minutes. I stood and watched, and I know it was done right.

Funny, I asked Mike at Superformance about this issue. He claimed that less then 20 sets of wheels out of 500 sold needed the hub centering rings. When I asked if it was an issue with the tolerances of the wheel construction or the hubs themselves, he got pretty huffy at me. I never did get an answer. He says my rings are on the way. I'll report back.

Nuvolari....how tight were the rings on yours? Did you need to machine them on a lathe to fit? I recall another Fchatter had some difficulty with the fact that they were so tight.

Birdman
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Old 04-01-2005, 01:08 PM
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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.
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Old 04-02-2005, 12:13 PM
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Still trying to sort this one out!

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
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Old 04-02-2005, 12:39 PM
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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.
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Old 04-02-2005, 12:56 PM
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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?
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Old 04-02-2005, 01:38 PM
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abs and non abs interchangable?

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?
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Old 04-06-2005, 08:10 PM
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The domed convex wheels are often referred to as "ABS" wheels though in fact it is my understanding that many of the cars that have these wheels do not in fact have ABS. What happened, (I think...someone correct me if I'm wrong) was the hub/wheel offsets were changed in mid-production of 328s and the later ones used a larger offset, which necessitates use of a large offset wheel. The convex wheel was created to work with that hub. The center part being convex gives the offset needed. To be technically correct, you should refer to these wheels as convex, not ABS, though most everyone knows what you mean, and most of the time you would be right.

The 348, 355, 360 and all Mondials had a similar large offset. The earlier 328 "concave" wheels have the small offset that was used with the 308 series and early 328s. Because of that, if you put an early 328 wheel on a large-offset hub, the wheel will stick out too far, probably an inch outside the fender. Besides playing havoc with your steering geometry, it looks ridiculous. (Trust me, I tried it with my Mondial).

You can put large offset wheels on small offset hubs (i.e. go the other way) with the use of spacers to make large offset wheels into small offset wheels, but you can't really do what you want to do.

What you can do is use large offset wheels from a 348, 355 or 360 on your large-offset 328.

Birdman
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Old 04-06-2005, 08:12 PM
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I thought I would post a pic of the car with the new wheels, not that you all haven't seen these wheels all over this site.

Still waiting for the hubcentric rings....

Birdman
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File Type: jpg 308_wheels_640.jpg (51.5 KB, 1068 views)
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Old 04-06-2005, 09:33 PM
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Quote:
Originally Posted by Verell
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).
(E) all of the above.

By jove, I think he's got it!
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Old 04-06-2005, 09:39 PM
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(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.
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