LA_Z06

I came across this thread where two different forum members have had the OEM Speedline wheels crack:
https://www.corvetteforum.com/forums...ck-wheels.html

I haven't heard of this before as I thought the Speedlines are pretty strong even though they aren't forged so there should be no problems running these wheels with sticky track rubber.

Now, I know that any wheel no matter how strong can fail, crack, etc. for different reasons (pothole, previous damage, etc.) but has anyone else had any issues at the track with OEM wheels and track tires?

argonaut

Stay away from chrome or powder coated wheels - both make them more brittle. Standard finish Speedlines have a good "track" record in both racing an advanced/instructor level DE, with or without slicks.

Now having said that - buying used ones is a mixed bag unless you are certain of their history. At this point some of the used ones are 10+ years old and may have been subjected to a brutal life. You can get new ones from House of Wheels.

shane p

How does powder coating make a wheel more brittle?

firebirdfan

It tempers the material. Powdercoating requires curing the paint at about 350-400*F. This can temper the aluminum and increase it's overall strength, however, the material becomes more brittle as a result. If you exceed the tempered strength, it cracks instead of just bending.

LA_Z06

Good points to consider. I was a bit shocked that an OEM wheel with sticky tires would fail considering that OEM wheels are put through many different stress tests and that Speedline generally makes pretty good wheels.

Z06Tracker

I have bought many of them used and raced them for years without any problems. Just check them when you clean them.

shane p

At that temp you might temper them a little bit depending on the grade of aluminum it is
tempering is something you do after you heat treat(make harder) a material to bring back ductility and malleability just the opposite of making brittle.

kmagvette

All wheels have the potential to fail. I, and others, have cracked wheels from very well known after market manufacturers of track wheels...in most cases this took many years to accomplish this. If you are routinely sliding into curbing sideways you will stress the wheels quicker. Does not matter if they are Speedline, BBS, CCW, iForged, etc.

Check whatever wheels you have regularly.

LA_Z06

Does anyone know if the gloss black or grey colored C6 Z06 wheels that came from GM/speedline (spyder, centennial, or carbon package wheels) were painted or powder coated by GM/Speedline? I'm guessing they would have been painted vs the powder coating, but would be good to know for sure.

chpmnsws6

Wheels should be considered a consumable in track life. It doesn't matter what wheel you have.