Mysterious damage to my OEM GT4 wheel .. any thoughts ?! [New Video uploaded]
03-22-2017, 06:27 PM
#61
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Thread Starter
Not that it's worth much but this is where I would be which then resulted in the buckling. It's also why I really don't understand why Porsche don't want the rim back. It's a very important safety component on one of their halo cars which is produced by and external supplier and at the very least has a pretty descent chance of being a manufacturing defect and could (would) have led to a catastrophic failure causing a serious accident. Someone had a serious brain fade back at Porsche HQ.
+100 ... this is a professional reaction. well said
03-23-2017, 12:28 AM
#63
Rennlist Member
One way to eliminate the turning is to buy another wheel and go to the track. My guess is that the new wheel does not bend. COTA is a FIA track and I am all over the curbs...for a lot of laps. No visible damage. Sorry to see this.
03-23-2017, 12:32 AM
#64
Rennlist Member
Great way to easily see, wonderful suggestion
but OP stated did not want to dismount tire to show Porsche nothing was monkeyed with or even caused by the dismounting
Email this link to several Porsche employees in Germany, perhaps a different route will get the right person's attention
but OP stated did not want to dismount tire to show Porsche nothing was monkeyed with or even caused by the dismounting
Email this link to several Porsche employees in Germany, perhaps a different route will get the right person's attention
03-23-2017, 02:02 AM
#66
Advanced
Thread Starter
Great way to easily see, wonderful suggestion
but OP stated did not want to dismount tire to show Porsche nothing was monkeyed with or even caused by the dismounting
Email this link to several Porsche employees in Germany, perhaps a different route will get the right person's attention
but OP stated did not want to dismount tire to show Porsche nothing was monkeyed with or even caused by the dismounting
Email this link to several Porsche employees in Germany, perhaps a different route will get the right person's attention
03-23-2017, 02:23 AM
#67
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Someone on rennlist posted that the wheels are flow formed. The weight on a wide 20" wheel would also be a good hint as to whether it's cast or flow formed. If there's a manufacturing defect in this process, perhaps it could explain a weaker barrel while the spokes look fine.
Flow formed wheels are cast with smaller barrels, then the barrel is drawn out between two rollers to get the correct width. It saves money vs. a forged wheel, while saving weight and increasing strength vs. a cast wheel. It's kind of a middle ground for cost/weight between regular cast and forged wheels. Here's a video of the general process (skip to 3:10)
Flow formed wheels are cast with smaller barrels, then the barrel is drawn out between two rollers to get the correct width. It saves money vs. a forged wheel, while saving weight and increasing strength vs. a cast wheel. It's kind of a middle ground for cost/weight between regular cast and forged wheels. Here's a video of the general process (skip to 3:10)
03-23-2017, 04:37 AM
#70
Rennlist Member
Missed that fact somewhere along the way. I know it's a late reaction, but that strikes me as a little dishonest because with such a similar design, I'd think it would be natural to assume similar construction.
Last edited by Yargk; 03-23-2017 at 05:16 AM.
03-23-2017, 09:12 AM
#71
Rennlist Member
For anyone that missed it, this is the older thread that confirmed the flow forming process: https://rennlist.com/forums/gt4/8971...ls-forged.html
03-24-2017, 07:26 AM
#72
Rennlist Member
Man I like the analysis you've done in the previous post .. the yellow marks made it very clear that the bends are identical. great stuff.
I really appreciate your scientific brainstorming .. keep it up guys and I will provide more info so we can have a very interesting investigation/R&D post !!
I really appreciate your scientific brainstorming .. keep it up guys and I will provide more info so we can have a very interesting investigation/R&D post !!
Someone on rennlist posted that the wheels are flow formed. The weight on a wide 20" wheel would also be a good hint as to whether it's cast or flow formed. If there's a manufacturing defect in this process, perhaps it could explain a weaker barrel while the spokes look fine.
Flow formed wheels are cast with smaller barrels, then the barrel is drawn out between two rollers to get the correct width. It saves money vs. a forged wheel, while saving weight and increasing strength vs. a cast wheel. It's kind of a middle ground for cost/weight between regular cast and forged wheels. Here's a video of the general process (skip to 3:10)
https://youtu.be/8ou1tmWeATI?t=3m12s
Flow formed wheels are cast with smaller barrels, then the barrel is drawn out between two rollers to get the correct width. It saves money vs. a forged wheel, while saving weight and increasing strength vs. a cast wheel. It's kind of a middle ground for cost/weight between regular cast and forged wheels. Here's a video of the general process (skip to 3:10)
https://youtu.be/8ou1tmWeATI?t=3m12s
03-24-2017, 09:51 AM
#73
Rennlist Member
...I really don't understand why Porsche don't want the rim back. It's a very important safety component on one of their halo cars which is produced by and external supplier and at the very least has a pretty descent chance of being a manufacturing defect and could (would) have led to a catastrophic failure causing a serious accident. Someone had a serious brain fade back at Porsche HQ.
Some of the other links you guys added are great...love the guy in Germany that says the German language is very precise and engineering-like and if the GT4 wheels were forged they would say so because that's how they think. Flow-forming video is cool; must give properties similar to forging. Working (deforming) the metal strengthens it with proper heat treat (usually at the expense of it becoming more brittle/less ductile)...after seeing it, I suppose they may not need a final machining pass on the barrel.
03-24-2017, 10:16 AM
#74
Someone on rennlist posted that the wheels are flow formed. The weight on a wide 20" wheel would also be a good hint as to whether it's cast or flow formed. If there's a manufacturing defect in this process, perhaps it could explain a weaker barrel while the spokes look fine.
Flow formed wheels are cast with smaller barrels, then the barrel is drawn out between two rollers to get the correct width. It saves money vs. a forged wheel, while saving weight and increasing strength vs. a cast wheel. It's kind of a middle ground for cost/weight between regular cast and forged wheels. Here's a video of the general process (skip to 3:10)
https://youtu.be/8ou1tmWeATI?t=3m12s
Flow formed wheels are cast with smaller barrels, then the barrel is drawn out between two rollers to get the correct width. It saves money vs. a forged wheel, while saving weight and increasing strength vs. a cast wheel. It's kind of a middle ground for cost/weight between regular cast and forged wheels. Here's a video of the general process (skip to 3:10)
https://youtu.be/8ou1tmWeATI?t=3m12s
