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Old 06-19-2019, 09:49 AM
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Default Aerodynamic lift or ?

I'm working through something that happened last weekend at WG, and wanted to get concurrence or second opinions.

I was heading out of 2 and started transitioning across the track for 3. Around the middle of the track, my steering wheel got real light and the car stopped responding to input, resulting in me heading straight for the outside wall. I got off the gas, got some grip up front, and made it through.

My initial impression was I was getting front end lift and it might be time to start thinking about aero. Watching the video, though, has given me small doubts.

On the video as I start crossing the track, you can hear a whirring and thumping sound coming from the car as I lose steering feel. Is that the sound tires make when they get light? Or could I have picked up something that made the car respond in this way?

I can post a video of it once I find an editor I like.
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Old 06-19-2019, 10:27 AM
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Sounds more like a shock (rebound-car not sitting down fast enough) issue/mechanical or there was fluid on the track.......doesnt sound like fun though.
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Old 06-19-2019, 12:43 PM
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I was thinking fluid on the track - shock rebound would be for a bumpier area than the esses, wouldn't it (unless it were really severe)?
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Old 06-19-2019, 01:48 PM
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I had a similar issue issue 'code brown!' at the same spot on Saturday, first run I believe, 5th or 6th lap. The rear end of the car stepped out (slide not bounced). I had to counter steer slightly to correct which took me very close to the inside wall over the bridge. Tires should have been heated up decently (although slightly low pressure in first run). There was also a pretty high side wind that morning and also at other times over the weekend.
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Old 06-19-2019, 02:43 PM
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Thanks, guys. That's what i was thinking about - if I hit some fluid.

Quote:
Originally Posted by vranko View Post
I had a similar issue issue 'code brown!' at the same spot on Saturday, first run I believe, 5th or 6th lap. The rear end of the car stepped out (slide not bounced). I had to counter steer slightly to correct which took me very close to the inside wall over the bridge. Tires should have been heated up decently (although slightly low pressure in first run). There was also a pretty high side wind that morning and also at other times over the weekend.
Same for me, first session on Sat, 5-6 laps in. Didn't happen any other time. Scared me good.
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Old 06-19-2019, 02:52 PM
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Quote:
Originally Posted by Dr K View Post
I was thinking fluid on the track - shock rebound would be for a bumpier area than the esses, wouldn't it (unless it were really severe)?
2 to 3 is the crest of a hill, car becomes light...doesnt only need a bump for shock settings to matter... just up and down movement
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Old 06-19-2019, 03:36 PM
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Quote:
Originally Posted by Modian View Post
Same for me, first session on Sat, 5-6 laps in. Didn't happen any other time. Scared me good.
Interesting. I suspect it was the cross wind right at the crest of the crown / hill at T3.
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Old 06-19-2019, 04:39 PM
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Probably like an aircraft accident; a combination of things making contributions to the final outcome. I seem to remember you have a spoiler on the rear but no splitter on the front? If so, that might have contributed as well. If no, well just go onto the next post.....
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Old 06-19-2019, 05:05 PM
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Quote:
Originally Posted by vranko View Post
Interesting. I suspect it was the cross wind right at the crest of the crown / hill at T3.
That wind was well over 20 Knots at times, would not surprise me if gusts had not gone up 30 to 40, coincide when a tad light and hop skip and jump.
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Old 06-19-2019, 05:28 PM
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