Throttle induced understeer - solution?
10-24-2008, 07:03 PM
#16
Nordschleife Master
understeer on 2? where? I would guess as you drop from the top down to apex. Next time try to get Ted JR. in the right seat. That is not a corner for challenges on exit. I still would get Gregg for the setup and TedJR for a test ride. Kitch will sometime let you come out for a "power lunch" to test and tune.
10-24-2008, 08:21 PM
#17
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understeer on 2? where? I would guess as you drop from the top down to apex. Next time try to get Ted JR. in the right seat. That is not a corner for challenges on exit. I still would get Gregg for the setup and TedJR for a test ride. Kitch will sometime let you come out for a "power lunch" to test and tune.
10-25-2008, 04:19 AM
#18
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Let's not forget that at the time you apply throttle as above, the diff will lock up (assuming your diff is still working 
) which will push you wide as well as both rear wheels want to track straight ahead.
) which will push you wide as well as both rear wheels want to track straight ahead.
10-25-2008, 12:14 PM
#19
Nordschleife Master
when my can is having issues I let my mechanic (built Peter Gregg and Haywood's 935s) take a few laps. More often than not he says " feels fine - drive better"
10-25-2008, 12:14 PM
#20
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I think first u adjust your Swaybar settings. I think 171mph has full stiff rear and full soft front and he is on motons. Check LSD too. Behavior with busted LSD is unstable straightline braking( front hunting and rear moving laterally side to side). Also on slower turns could not rotate out with power. Regards. Mike
10-25-2008, 01:47 PM
#21
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then he proceeds to beat me by2-3 seconds driving 7/10 with me in the car, hahah
10-26-2008, 07:32 PM
#22
What is your front camber set at? While adjusting the bars can certainly help, if you have too little camber, you will still sacrifice grip. I found a similar behavior which I dialed out with the bars (camber was at -1.8 for stock class autox) but when realigning with more negative camber up front, not only does the car feel more neutral but the grip is amazing (-2.5 up front for track). Note that you still may have to tweak the bars after adjusting the camber.
10-26-2008, 11:34 PM
#23
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I think first u adjust your Swaybar settings. I think 171mph has full stiff rear and full soft front and he is on motons. Check LSD too. Behavior with busted LSD is unstable straightline braking( front hunting and rear moving laterally side to side). Also on slower turns could not rotate out with power. Regards. Mike
So far, I've experienced throttle induced understeer only on the skid pad and only during the first time outing. Like Mooty said, the car *should* push a bit around tight turns and you can adj it with throttle and turn in if you want to slide around a bit. I would take it on to the skid pad and practice. I've the front sway bar set at one hole from full stiff and rear at one hole from full soft. -2.8 front camber, slightly toe-out up front and slightly toe-in for rear.
10-27-2008, 04:34 AM
#24
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Guys, thanks for all of your suggestions.
Dell: At my speed, it isn't "Too fast at entry". LOL!
Mike: Reset front bar. Front: One from full soft. Rear: One from full hard. Other than needing more front neg camber. This should help this high speed power induced understeer.
Leigh and Mooty: You are correct, this occurs during exiting while I am squeezing the throttle back on. For low speed (tight) cornering, continually working on better driver input.
JMeager, Mike, Datax: Good point, LSD is still functioning.
Gordon: Am still trying to find the correct or good line through 8.
JohnR: Based on what you describe, believe that is the answer. Not enough neg front camber.
PJ: Ted is the man! Could of heard him wrong? Thus, the question to the group.
Dell: At my speed, it isn't "Too fast at entry". LOL!
Mike: Reset front bar. Front: One from full soft. Rear: One from full hard. Other than needing more front neg camber. This should help this high speed power induced understeer.
Leigh and Mooty: You are correct, this occurs during exiting while I am squeezing the throttle back on. For low speed (tight) cornering, continually working on better driver input.
JMeager, Mike, Datax: Good point, LSD is still functioning.
Gordon: Am still trying to find the correct or good line through 8.
JohnR: Based on what you describe, believe that is the answer. Not enough neg front camber.
PJ: Ted is the man! Could of heard him wrong? Thus, the question to the group.
10-27-2008, 10:54 AM
#25
Nordschleife Master
Guys, thanks for all of your suggestions.
Dell: At my speed, it isn't "Too fast at entry". LOL!
Mike: Reset front bar. Front: One from full soft. Rear: One from full hard. Other than needing more front neg camber. This should help this high speed power induced understeer.
Leigh and Mooty: You are correct, this occurs during exiting while I am squeezing the throttle back on. For low speed (tight) cornering, continually working on better driver input.
JMeager, Mike, Datax: Good point, LSD is still functioning.
Gordon: Am still trying to find the correct or good line through 8.
JohnR: Based on what you describe, believe that is the answer. Not enough neg front camber.
PJ: Ted is the man! Could of heard him wrong? Thus, the question to the group.
Dell: At my speed, it isn't "Too fast at entry". LOL!
Mike: Reset front bar. Front: One from full soft. Rear: One from full hard. Other than needing more front neg camber. This should help this high speed power induced understeer.
Leigh and Mooty: You are correct, this occurs during exiting while I am squeezing the throttle back on. For low speed (tight) cornering, continually working on better driver input.
JMeager, Mike, Datax: Good point, LSD is still functioning.
Gordon: Am still trying to find the correct or good line through 8.
JohnR: Based on what you describe, believe that is the answer. Not enough neg front camber.
PJ: Ted is the man! Could of heard him wrong? Thus, the question to the group.
10-27-2008, 03:20 PM
#26
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) camber effects of less bodyroll outweigh the negative weight transfer effects.Not the case with a GT3 with stiff springs?
10-27-2008, 04:15 PM
#27
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GT3 will always push on corner exit on tight turns and full gas. The front end gets really light, and there is practically no weight on the front axle. Making the car neutral in such conditions, will make it too loose at other places.
Try a later apex and trail braking. A stiffer rear bar will help better than a softer front bar, because of the light front end on tight corner exits.
Try a later apex and trail braking. A stiffer rear bar will help better than a softer front bar, because of the light front end on tight corner exits.
10-27-2008, 05:51 PM
#28
Nordschleife Master
GT3 will always push on corner exit on tight turns and full gas. The front end gets really light, and there is practically no weight on the front axle. Making the car neutral in such conditions, will make it too loose at other places.
Try a later apex and trail braking. A stiffer rear bar will help better than a softer front bar, because of the light front end on tight corner exits.
Try a later apex and trail braking. A stiffer rear bar will help better than a softer front bar, because of the light front end on tight corner exits.
10-27-2008, 06:42 PM
#29
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70 mph in, 110 mph out with understeer? wow... even though his spring rates at the back are high (900#).
In this case I would add one click on rear compression and rebound, and move the rear bar at one from stiff.
I ran my car with the front and rear bar at one from stiff, with the rear at full stiff for autoX. This was on wider wheels and tires: 285/335 on 10"/12" wheels.
The 235 is a skinny tire.
In this case I would add one click on rear compression and rebound, and move the rear bar at one from stiff.
I ran my car with the front and rear bar at one from stiff, with the rear at full stiff for autoX. This was on wider wheels and tires: 285/335 on 10"/12" wheels.
The 235 is a skinny tire.
10-27-2008, 11:05 PM
#30
Nordschleife Master
70 mph in, 110 mph out with understeer? wow... even though his spring rates at the back are high (900#).
In this case I would add one click on rear compression and rebound, and move the rear bar at one from stiff.
I ran my car with the front and rear bar at one from stiff, with the rear at full stiff for autoX. This was on wider wheels and tires: 285/335 on 10"/12" wheels.
The 235 is a skinny tire.
In this case I would add one click on rear compression and rebound, and move the rear bar at one from stiff.
I ran my car with the front and rear bar at one from stiff, with the rear at full stiff for autoX. This was on wider wheels and tires: 285/335 on 10"/12" wheels.
The 235 is a skinny tire.