Cracked a Mille Miglia cup 2 wheel

Tim L · 05-28-2003, 06:10 AM

For those of you who are tracking these wheels beware!
Luckily only 2 of the five spokes cracked and I didn’t lose it at 110 mph!!

I had just inspected the wheels and there was no sign of cracks.

Tim

avi8torny · 05-28-2003, 06:31 AM

I have always wondered if these wheels would hold up on a car that actively tracked in DE's....the only way for sure to find out if the others have hairline cracks to have them magnifluxed. Frightening for sure.

ChrisBennet · ChrisBennet's Garage

A friend of mine noticed the crack through the spoke of one of his Mille Miglia Cup 2 wheels when he was loading it on the trailer after having some engine problems at the track. The engine problems may have saved him some body work...
-Chris

APKhaos · 05-28-2003, 08:16 AM

THere's a pic in the archives of a MM Cup wheel that suffered catastrophic failure at a DE event - the hub literally ripped away from all of the spokes.

Using these wheels on the street is risky enough. Using them on the track is insanity!

tdorsey835 · 05-28-2003, 09:40 AM

Holy #@*! You guys have got me thinking... when I bought my car, the previous Owner had installed aftermarket (not Porsche OE) 5 spoke wheels that I have always referred to as C2 Turbo wheels. He said he bought them from the wheel co. that always has the 2 page ad in the panorama with the 50/50 picture of the Fuch cleaned and dirty. ( I think they might be Wheel Enhacement I dont have the mag in front of me) I dont' track or DE the car, only street. Can someone post a picture of the Mille Miglia cup 2- I think I might have them. And if I do- now what?

ChrisBennet · ChrisBennet's Garage

It wouldn't bother me personally to use them on the street if I knew their history. I think sticky track tires are what fatigues them. We're starting to see cracks in Fuchs which makes me wonder about using them as 17" wheel centers...
-Chris

APKhaos · 10:49 AM

This is the example I mentioned above. Thought it was worth finding and posting again to give people who have these wheels a real idea of what can happen.

Originally posted by Bill Verberg; happened at a Watkins Glen DE last year.

I agree with Chris - normal street use is probably OK, but check them carefully after any decent curb impact etc. Just don't risk them on the track.

Kevin Stewart · 05-28-2003, 10:31 AM

Not to stir you guys up, but are you dropping the wheels off the apex and bumping the pavement when the tire comes back on the track? or hitting the concrete curbs on the apex portion, just wondering, Kevin

old_skul · 05-28-2003, 10:44 AM

To think I almost bought a set of these wheels.

NoLift911 · 05-28-2003, 01:46 PM

I have a set of MM Cup II's that I have tracked once. I often wondered about this. I think your chances of this happening are very rare. I would head back out onto the track but an upgrade is def in the future.

Also what type of cars is this happening on? A heavily modified (suspension wise) with track rubber is no place for these wheels.

My car with minimal mods for a few DE's is fine IMO.

How much abuse are you subjecting wheels that are not meant for this application?

-Jeff
nolift911@hotmail.com

Tim L · 05-28-2003, 01:58 PM

I had these wheels on an 84 911 with kuhmo victoracers and stiffer suspension. I originally purchased these wheels for an occasional DE but as you know an occasional DE can turn into a habit. I just purchased some fikses so I wont be using these on the track.

Tim

cowtown · 05-28-2003, 02:09 PM

Yikes. I've got MM C2T wheels on my '88 Carrera, which I've tracked 6 times, plus autocrossed a few times. Stock suspension except for adjustable Konis. Street tires only. I've had no problems with them, but I'm definitely going to keep a close eye on them!

RickM · RickM's Garage

Could one use the flourescent dye that is used to locate "invisible" cracks in a head on these wheels as well?

05-28-2003, 02:29 PM

The MilleMiglias are built under license from Porsche AG and have TÜV approval.

So perhaps any other aftermarket lower price range wheel will do the same in racing conditions? I wonder how tele dials or cookie cutters would behave under identical racing conditions?

MMARSH · MMARSH's Garage

The fact of the matter is that Wheels, whether they are Fuchs (stock or modified) or racing BBS wheels have a lifespan. My Mechanic has seen cracked wheels from every wheel maker. Thats why Pro teams cycle thru their wheels. Obviously some types will last longer then others, but I would say if you DE or Race the car regularly with stickey rubber, you definately want to keep an eye on them.

island911 · 05-28-2003, 04:39 PM

Quote:

Originally posted by MMARSH
The fact of the matter is that Wheels, whether they are Fuchs (stock or modified) or racing BBS wheels have a lifespan. My Mechanic has seen cracked wheels from every wheel maker. . . .

True, but not all wheels respond to cracks equally. Materials and structural geometry will make big differences in how far, and how fast a crack will propagate.

I think these posts (w/ empirical datum) are quite useful in sorting out, the tough wheels from the peanut-brittle.

Does anyone have a picture or a story of a real Fuchs wheel having a catastrophic failure? (not just a started crack) . . .maybe Fuchs haven't been used or around long enough.