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Discussion Starter #1
Hey guys, here is a video of my runs this weekend at the Michelin Proving Grounds in SC. This was my first event with the Hankook RS3's. They stuck incredibly well longitudinally but not as much as I was expected laterally. The car would understeer until I hit the throttle and then oversteer. The tires were very warm to the touch after each run by by the next run (20-30 min) they were cold again. I need to figure out how to keep them warm. My third lap was the fastest but I don't know how. It seemed like I was sliding all over the place. I know there are a lot of autoX veterans on here. Any tips or advice would be welcome!

 

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Neat software. Would be great to see brake and throttle input if possible. I have bluetooth to my cellphone on my ECM but I haven't used it yet to overlay video.

You can see a clear improvement run to run to the first half of run 4. In general, I'd say you were too conservative around the turns. IMO, when on street tires, if they aren't squealing, you are leaving time on the table. Looks like all that power makes it tricky, throttle seems to be on or off except for the first part of the last run. You were in 2nd gear, right?

What are your spring rates, dampers, and sway bars? Lots of body roll, which is normal for these cars until you really up the rates. Also, understeer in, throttle oversteer out is what these cars do until you fix the rear via PM3L or torque arm. I take it you still have quadrabind rear? How big are the wheels and tires? Square? Staggered?

Re: tire warming, people make blankets out of reflective material from home depot. TireBlankets.jpg Photo by Kevin_Doe | Photobucket
 

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Discussion Starter #4
Neat software. Would be great to see brake and throttle input if possible. I have bluetooth to my cellphone on my ECM but I haven't used it yet to overlay video.

You can see a clear improvement run to run to the first half of run 4. In general, I'd say you were too conservative around the turns. IMO, when on street tires, if they aren't squealing, you are leaving time on the table. Looks like all that power makes it tricky, throttle seems to be on or off except for the first part of the last run. You were in 2nd gear, right?

What are your spring rates, dampers, and sway bars? Lots of body roll, which is normal for these cars until you really up the rates. Also, understeer in, throttle oversteer out is what these cars do until you fix the rear via PM3L or torque arm. I take it you still have quadrabind rear? How big are the wheels and tires? Square? Staggered?

Re: tire warming, people make blankets out of reflective material from home depot. TireBlankets.jpg Photo by Kevin_Doe | Photobucket
Oh man, I would love throttle and brake input! But without OBDII I don't know how I would get it without a lot of wiring and sensors. Besides for that, all the software I used was free. And the camera was only $100 new and I use it as a dashcam.

Yeah I feel like I was too conservative too. I was trying to be smooth enough they wouldn't squeal. For some reason, I forgot about the fact that they have more grip with some slip. Do you know what would cause the oversteer going into the second cone on the second slalom? Was it because the rear end was too light? Yeah I was in 2nd for the entire run each time.

No clue on the suspension stats. I bought the car with most all of the work done. I know it has steeda springs and rear sway bar. And Edelbrock shocks. Still has the quadrabind. I have an MM panhard bar but I'm waiting for it to be cooler and get more seat time before installing it. Also trying to decide if I should do PM3L with it. With this much power I really don't want to break anything. I want a torque arm but don't have the $$$.

Wheels and tires are square. 18x9.5 and 275/35r18.
 

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The oversteer in the 2nd slalom is because you were coming into it decelerating and turning right, so it was front-heavy and the left side suspension was compressed and loaded with energy waiting to be released. Once it did, it pitched the rear end to the right. Rallyists do that on purpose to get the car to rotate quickly on slippery pavement, e.g. the Scandinavian Flick.
 

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Discussion Starter #6
The oversteer in the 2nd slalom is because you were coming into it decelerating and turning right, so it was front-heavy and the left side suspension was compressed and loaded with energy waiting to be released. Once it did, it pitched the rear end to the right. Rallyists do that on purpose to get the car to rotate quickly on slippery pavement, e.g. the Scandinavian Flick.
Ok thanks! So would I avoid that by applying some throttle when it starts to oversteer? I know the right answer is stiffer sway bar or springs but I don't have money for that right now.
 

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Yes, give it just a little throttle to shift load back to the rear. Emphasis on a little. The best approach is to anticipate it though. Skip Barber teaches "CPR" for skid recovery which is the exact same principle here: Correct...Pause...Recover. The Pause is waiting while the suspension loads, the Recover is getting started on the opposite steering correction in time to catch the swing the other way when the suspension releases its energy.
 

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Discussion Starter #8
Ok great. So just give a little throttle and be smoother in the transitions. I'll try to remember that at the next event. Thanks!
 
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