Car unsettles under strong braking
06-26-2006, 01:23 PM
#16
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Confusing ..... 
AW,
...it can be caused by to much rear bias.
RODNEYR,
...A known issue with the car is the Front bias is too high ...
MIKE K,
....I have found that a slightly more aggressive pad in the rear will help with bias .
AW,
...it can be caused by to much rear bias.
RODNEYR,
...A known issue with the car is the Front bias is too high ...
MIKE K,
....I have found that a slightly more aggressive pad in the rear will help with bias .
06-26-2006, 01:29 PM
#17
Actually, you need a less aggressive pad in the rear. If the rear pad is relatively too aggressive, you will loose traction in the rear before the front causing the rear to step out.
In this case, my best guess is too much negative camber, although you should trigger abs.
AW
In this case, my best guess is too much negative camber, although you should trigger abs.
AW
06-26-2006, 03:06 PM
#18
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First thing - get your air pressure down as I think that 40 will cause you to get squirelly...however, you do not mention that your front abs or rear abs is triggered.
I run more camber than you and I have not experienced that feeling (then again, my other car is a viper and I may just used to a nice loose feel in the braking zone!!!).
I do suspect your toe in the rear.
FYI - I run stock front splitter and OEM rear wing & settings.
I am assuming that you are smoother than a freshly waxed supermodels leg during you initiall braking, gradual build of brake and then gradual ease into the turn. If not, your back end might be a tad "jacked" just before turn in and result a very loose feel (especially if combined with tires, air temp, and possible off toe).
It is good you are driving!!
I run more camber than you and I have not experienced that feeling (then again, my other car is a viper and I may just used to a nice loose feel in the braking zone!!!).
I do suspect your toe in the rear.
FYI - I run stock front splitter and OEM rear wing & settings.
I am assuming that you are smoother than a freshly waxed supermodels leg during you initiall braking, gradual build of brake and then gradual ease into the turn. If not, your back end might be a tad "jacked" just before turn in and result a very loose feel (especially if combined with tires, air temp, and possible off toe).
It is good you are driving!!
06-26-2006, 04:13 PM
#19
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LastGT3,
Last ? ...
"...I am assuming that you are smoother than a freshly waxed supermodels leg ..." No, I am afraid not... I surely have to improve here ! ( more wax, better legs )
Why is it that I did not feel this issue with my TT at the same corner ?? Could be the bigger weight ? Is the TT brake bias the same ?
Last ? ...
"...I am assuming that you are smoother than a freshly waxed supermodels leg ..." No, I am afraid not... I surely have to improve here ! ( more wax, better legs )
Why is it that I did not feel this issue with my TT at the same corner ?? Could be the bigger weight ? Is the TT brake bias the same ?
06-26-2006, 04:26 PM
#20
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lastGT3 because I think I have the last 05 for Canada.
No idea on the tt except you have more weight on the front axel which would make it stick and therefore point more on turn initialition without "smooth like a freshly waxed supermodel's leg"...
Still think your air is too high at 40 hot - I have been advised 35-56 hot. Thats what i use and it seems OK. I also run 35 psa on the MPSC hot.
My tracks straight is about 235-240km before braking into a 140 km turn.
No idea on the tt except you have more weight on the front axel which would make it stick and therefore point more on turn initialition without "smooth like a freshly waxed supermodel's leg"...
Still think your air is too high at 40 hot - I have been advised 35-56 hot. Thats what i use and it seems OK. I also run 35 psa on the MPSC hot.
My tracks straight is about 235-240km before braking into a 140 km turn.
06-27-2006, 12:02 AM
#21
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Harry - 1) You need a front splitter!
2)One of the most common reasons for the back end getting unstable under braking is alignment. Note, that bumps will knock the camber and toe adjustment out of the right settings quite easily. Many on this list have switched to alternate rear control arms to make the alignment more secure. Bumpy roads will cause the camber adjustment to change and can cause handling problems.
3) The GT3 is very front biased under braking. Many of us have found that a more aggressive pad in the rear helps braking and also reduces wear on the front rotors. On the other hand with RS 19's all around I had no instability under braking from 230 KPH on Cup tires.
4) Lastly 40 lbs hot is only a startng point. Do try lowering to 38 in back and 36 in front. Be sensitive to the tire rolling over on the shoulder though. Do not exceed 40 lbs hot. Be sure your tire gauge is accurate.
Best,
2)One of the most common reasons for the back end getting unstable under braking is alignment. Note, that bumps will knock the camber and toe adjustment out of the right settings quite easily. Many on this list have switched to alternate rear control arms to make the alignment more secure. Bumpy roads will cause the camber adjustment to change and can cause handling problems.
3) The GT3 is very front biased under braking. Many of us have found that a more aggressive pad in the rear helps braking and also reduces wear on the front rotors. On the other hand with RS 19's all around I had no instability under braking from 230 KPH on Cup tires.
4) Lastly 40 lbs hot is only a startng point. Do try lowering to 38 in back and 36 in front. Be sensitive to the tire rolling over on the shoulder though. Do not exceed 40 lbs hot. Be sure your tire gauge is accurate.
Best,
