Gumby wheel question
Safety Car
Joined: May 2011
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From: Oshawa, Ontario
Team Owner
Joined: Mar 2008
Posts: 21,502
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From: Southern Utah
I may be wrong, it would not be the first time, but I have not seen anything from the company that says Speedline makes forged wheels. The '07 chrome 'wagon wheel' on the C6 was cast by Speedline...it is obvious by looking at the inside of the wheel...all the writing identifying the different specs is cast into the mating hub area of that wheel. The only wheel on a C6 that was forged was the gumby, which was forged by Superalloy in Taiwan.
Also, I know that Google is my friend...I'm interested in having a discussion, not a nastiness contest.
Also, I know that Google is my friend...I'm interested in having a discussion, not a nastiness contest.
Safety Car
Joined: May 2011
Posts: 3,807
Likes: 508
From: Oshawa, Ontario
I may be wrong, it would not be the first time, but I have not seen anything from the company that says Speedline makes forged wheels. The '07 chrome 'wagon wheel' on the C6 was cast by Speedline...it is obvious by looking at the inside of the wheel...all the writing identifying the different specs is cast into the mating hub area of that wheel. The only wheel on a C6 that was forged was the gumby, which was forged by Superalloy in Taiwan.
Also, I know that Google is my friend...I'm interested in having a discussion, not a nastiness contest.
Also, I know that Google is my friend...I'm interested in having a discussion, not a nastiness contest.
Le Mans Master
Joined: Jun 2011
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From: Charlotte NC
St. Jude Donor '14-'15
Racer
Joined: Jun 2012
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From: Hillsboro Oregon
It has been said that forging results in a tougher/stronger alloy wheel vs. cast wheels. Cast wheels are softer and the rim is prone to bending if you hit a pothole. I've heard this happening to OZ wheels, which are cast. I've yet to bend a rim on my Gumby's, and they've done battle with some formidable potholes.
Team Owner
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From: Far NW 'burbs of Chicago
St. Jude Donor '13
It has been said that forging results in a tougher/stronger alloy wheel vs. cast wheels. Cast wheels are softer and the rim is prone to bending if you hit a pothole. I've heard this happening to OZ wheels, which are cast. I've yet to bend a rim on my Gumby's, and they've done battle with some formidable potholes.
Modern casting techniques are much better than when I was a kid.
I've weighed several different sets of C6 wheels, both cast and forged. The weights are virtually identical, for street usage I would expect GM to save some weight with the forged wheels if it was practical.
All else being equal, I would prefer forged. But for street/A-X/HPDE use, the GM Corvette cast wheels seem to work very well. From other suppliers, maybe not so true.
Last edited by Gearhead Jim; Mar 15, 2013 at 09:06 PM.
Thread Starter
Instructor
Joined: Apr 2001
Posts: 1,484
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From: Raleigh NC
Thread with some good information. I posted this when I cracked a wheel on the Charlotte Motor Speedway. It's not a gumby but at the time I thought it was.
http://forums.corvetteforum.com/auto...nasa-hpde.html
http://forums.corvetteforum.com/auto...nasa-hpde.html
Racer
Joined: Jun 2012
Posts: 440
Likes: 6
From: Hillsboro Oregon
Thread with some good information. I posted this when I cracked a wheel on the Charlotte Motor Speedway. It's not a gumby but at the time I thought it was.
http://forums.corvetteforum.com/auto...nasa-hpde.html
http://forums.corvetteforum.com/auto...nasa-hpde.html
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Team Owner
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From: Southern Utah
Le Mans Master
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From: Charlotte NC
St. Jude Donor '14-'15
I think that what a fellow should do is not worry about wheel failures. Yes, every once in a while we hear about one, but they are exceedingly rare. When a cast wheel is struck and cracked, we have no idea whatsoever whether a forged wheel subjected to that same blow would have survived or not. We have no idea whether one particular pothole would have bent any wheel or not. All the oem wheels are far stronger than normal use would require, so we should be happy and enjoy whatever wheels we like the looks of.
Team Owner
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From: Southern Utah
Thread Starter
Instructor
Joined: Apr 2001
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From: Raleigh NC
I would also agree under normal situations, wheels hold up well. My cracked cast wheel (3 out of 5 spokes) happened while transitioning back on the Charlotte Motor Speedway in turn 1. I just wanted to point out if you enter the track too soon from the infield….. Your front right wheel just may not survive the transition. Passing on the knowledge. 
Passing on the knowledge.