Car unsettles under strong braking
#1
Pro
Thread Starter
Join Date: Dec 2002
Location: Madrid, Spain
Posts: 747
Likes: 0
Received 0 Likes
on
0 Posts
Car unsettles under strong braking
Under a rather long and hard braking at the end of a straight line, at 150 mph which is followed by a corner at 50 mph the car unsettles more than I would like . This happens at the middle to the end of the braking period. The feeling is that the front is struggling to find grip while loosing it's line. Nothing specially worrying but it obviously makes me loose some confidence and makes the entrance of the corner more difficult.
Could be that my car hasn't got the lip under the front bumper ? It will be installed next week, but I understand that it should help at high speeds and not necessarily under braking...
I am using Orange Pagids and steel brakes and Ps'2s with 40 pounds/hot pressure, swaybars to -1F and -2R. Roland's Kussumauls settings with only -1.5 camber on the front.
On the rest of the track I have nothing special to mention about the brakes ...
Could you please help me to get the "perfect" gt3...?
Could be that my car hasn't got the lip under the front bumper ? It will be installed next week, but I understand that it should help at high speeds and not necessarily under braking...
I am using Orange Pagids and steel brakes and Ps'2s with 40 pounds/hot pressure, swaybars to -1F and -2R. Roland's Kussumauls settings with only -1.5 camber on the front.
On the rest of the track I have nothing special to mention about the brakes ...
Could you please help me to get the "perfect" gt3...?
#5
Three Wheelin'
If it's not alignment, could possibly just be the track surface at that corner, or you unsettling the car by jumping on the brakes too hard initially. The latter makes a massive difference, both to stability and stopping distance.
#6
Rennlist Member
Is this a section of the circuit where you are threshold breaking in a straight line, downshifting, off the brakes, and then turning? or One where you are trailbraking into the turn?
Assuming the car and your transition into the corner are fine you may be at the limit of speed you can carry into the beginning of that turn.
Assuming the car and your transition into the corner are fine you may be at the limit of speed you can carry into the beginning of that turn.
Trending Topics
#8
Still plays with cars.
Lifetime Rennlist
Member
Harry - you NEED the front lip. Iwould also be suspicious of the rear alignment. The GT3 loses rear alignment rather easily. Bumpy roads and or tracks can knock the alignment out rather easily. Several people of this forum have installed different rear control arms to avoid unwanted camber changes.
Regards,
Regards,
#10
Pro
Thread Starter
Join Date: Dec 2002
Location: Madrid, Spain
Posts: 747
Likes: 0
Received 0 Likes
on
0 Posts
DanH,
the surface there is OK.Could be the braking technique ( I will work on that)...but it does not appear on other corners ( not as fasts as this one BTW)...
Enthusiast,
Threshold breaking in a straight line, downshifting, WHILE BRAKING, and then turning..
GT3 racer,
I do have Front Toe In
Bob,
I will check alignment and install the front lip
THANK YOU ALL !!!!!
the surface there is OK.Could be the braking technique ( I will work on that)...but it does not appear on other corners ( not as fasts as this one BTW)...
Enthusiast,
Threshold breaking in a straight line, downshifting, WHILE BRAKING, and then turning..
GT3 racer,
I do have Front Toe In
Bob,
I will check alignment and install the front lip
THANK YOU ALL !!!!!
#12
Three Wheelin'
Car unsettles under strong braking happens with my car all the time, and I had my alignment set using a Hunter machine. A known issue with the car is the Front bias is too high which causes the car to get unsettled. The issue is magnifed on a bumpy or rough surface.
Also, 40lbs hot pressure is fine with stock PS2's.
Also, 40lbs hot pressure is fine with stock PS2's.
#13
As far as I know, this is likely:
- too much front negative camber. Try removing 1degree or at least have it checked
- brake bias too much on the rear. I realize there is no brake bias but you could run less aggressive pads in the rear. I understand you feel the front is moving on you but could it be the rear?
I suspect the aero front lip effect is minimal below 100mph (in fact probably above 100mph as well, compared to the weight of the car).
I hope this helps.
AW
- too much front negative camber. Try removing 1degree or at least have it checked
- brake bias too much on the rear. I realize there is no brake bias but you could run less aggressive pads in the rear. I understand you feel the front is moving on you but could it be the rear?
I suspect the aero front lip effect is minimal below 100mph (in fact probably above 100mph as well, compared to the weight of the car).
I hope this helps.
AW
#15
Rennlist Member
I had similar issues while in florida. Things you can do to start are to bleed your lines to death and check your alignment( I had excessive front camber). After you can try different brake compounds. I have found that a slightly more aggressive pad in the rear will help with bias .