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7:14.3 GT3 at The Ring, real?

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Old 12-09-2016, 09:55 PM
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Stgrt
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Old 12-09-2016, 10:11 PM
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Originally Posted by Stgrt
Why does Porsche use MacPherson struts when nearly every competitor uses a double wishbone setup?
Because they're cheap a$$es. It's no coincidence they make the highest profit margin in automobiledom. But hey, at least it's only at the front now. That's up there with Corvettes still using a transverse composite leaf-spring front and back. Both approaches work, although neither optimal... but they save money. And yes, with 265 sticky tires, that could be a limiting factor.
Old 12-09-2016, 11:06 PM
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Old 12-10-2016, 12:16 AM
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Struts are simple, light, and cheaper. Plus on a Porsche there isn't too much load going through the front tires since the engine is in the wrong place, so it makes it harder to justify double wishbones. But then again their GTLM racecar has double wishbones and they are moving the engine to the right location next year...
Old 12-10-2016, 12:33 AM
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Old 12-10-2016, 12:35 AM
  #51  
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The weight distribution and especially the PMI of a rear engine is inherently disadvantaged for skidpad testing, but there's a rear grip acceleration advantage. There are always tradeoffs in different layouts.

I don't care too much for abstract skidpad results.
Old 12-10-2016, 12:45 AM
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Old 12-10-2016, 01:44 AM
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Originally Posted by Stgrt
True, I do not put a lot of weight on skidpad data either but it does stand out somewhat.

How do you account for the difference in braking? The weight distribution should give the GT3 RS an advantage yet the Z06 and Viper do quite a bit better.
Cough, wider front tires, cough.
Old 12-10-2016, 02:03 AM
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Old 12-10-2016, 03:30 AM
  #55  
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Originally Posted by Stgrt
That certainly has an impact. There are a lot of other variables as well such as weight distribution, weight, brake bias, alignment, etc. What effect, if any, do people think MacPherson struts have on the car versus if it had double wishbone? I do not intend to criticize the car or make it seem like MacPherson struts are an issue. Only that it seems like the competition uses a different geometry that potentially has performance differences.
It's much simpler than that. Tires are different. Viper comes with practically Hoosier-grade tires, and Corvette's MPSC2 tires are very different from Porsche's (or anyone else's) being practically slicks. Tires beat everything in the impact on traction on a skidpad or braking test (assuming suspension geometry is not screwed up). Aero has some impact too - both Corvette and ACR are particularly well-endowed in this area.
Old 12-10-2016, 05:34 AM
  #56  
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Originally Posted by stuntman
The weight distribution and especially the PMI of a rear engine is inherently disadvantaged for skidpad testing, but there's a rear grip acceleration advantage. There are always tradeoffs in different layouts.

I don't care too much for abstract skidpad results.
Thats why Motortrend use a Figure 8 layout as opposed to a 300ft/200ft pan.

The AMG ring time is impressive no matter which way you box and dice it. Nice lap from Chris Gebhardt
Old 12-10-2016, 06:22 PM
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Old 12-10-2016, 07:09 PM
  #58  
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Struts have very minimal camber gain, so theoretically they should be better than a double wishbone for braking, which the front tires camber in under compression, reducing the contact patch of the tire.
Old 12-10-2016, 07:30 PM
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Old 12-10-2016, 08:25 PM
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What passed the R like he was standing still (Cup car)? After a minute the R was so far behind you would assume it was more than 10 seconds, Are we to conclude that the car that passed him did the Ring in less than seven minutes?

Also, regarding the GT3 how is it he had a clear track? I don't think it was a factory sponsored run.


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