Track Related Mods
Congratulations on your first outing. Sounds like you got a lot a seat time.
If I remember correctly you have a stiff front sway bar. Do you have a matching rear sway bar as well. If your car has too much front sway bar it will lose grip over bumps and straight line breaking. And it will be more apt to push during cornering (understeer).
If I remember correctly you have a stiff front sway bar. Do you have a matching rear sway bar as well. If your car has too much front sway bar it will lose grip over bumps and straight line breaking. And it will be more apt to push during cornering (understeer).
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Joined: August 2, 2013
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From: Little north of Stuttgart, Germany
Hey guys, thanks for the feedback.
Sgwick, no relo brackets. I'm hoping not to have to go that route.
Redonblack, you are correct. I only have the front sway bar. Stock rear.
What I experienced yesterday were 2 things:
1) General lack of bite and brake torque. I had to push the pedal a lot harder than I remember to get into ABS and get close to 0.9g decel.
I'm running G-Lock R10s up front. They are supposed to be same compound as Carbotech XP10 (Carbotech fractured and G-Lock is a splinter of CT Brakes). R10s did not feel nearly as grippy or torquy as XP10s did. I'll try re-bedding them and give them one more track day.
2) Instability of rear of the car under heavy high speed straight line braking. Not major or super disruptive, but straight line braking should be drama free in cars with ABS and electronic brake force distribution.
On the rear axle I wapped to CT AX6 compound because my XP8s were more than 50% gone. This was a mistake. My first season I ran XP10 up front with stock rears (and stock suspension). I had similar rear end instability and lack of brake confidence i experienced yesterday, but back then the car actually stopped better!
There were no issues at all in cornering and even in trail braking.
So here is my game plan. I have 8 days before Mid-Ohio! I need better braking on that track. I'm going to put the XP8 back, re-bed the pads and do a comparison of performance.
Sgwick, no relo brackets. I'm hoping not to have to go that route.
Redonblack, you are correct. I only have the front sway bar. Stock rear.
What I experienced yesterday were 2 things:
1) General lack of bite and brake torque. I had to push the pedal a lot harder than I remember to get into ABS and get close to 0.9g decel.
I'm running G-Lock R10s up front. They are supposed to be same compound as Carbotech XP10 (Carbotech fractured and G-Lock is a splinter of CT Brakes). R10s did not feel nearly as grippy or torquy as XP10s did. I'll try re-bedding them and give them one more track day.
2) Instability of rear of the car under heavy high speed straight line braking. Not major or super disruptive, but straight line braking should be drama free in cars with ABS and electronic brake force distribution.
On the rear axle I wapped to CT AX6 compound because my XP8s were more than 50% gone. This was a mistake. My first season I ran XP10 up front with stock rears (and stock suspension). I had similar rear end instability and lack of brake confidence i experienced yesterday, but back then the car actually stopped better!
There were no issues at all in cornering and even in trail braking.
So here is my game plan. I have 8 days before Mid-Ohio! I need better braking on that track. I'm going to put the XP8 back, re-bed the pads and do a comparison of performance.
Congratulations on your first outing. Sounds like you got a lot a seat time.
If I remember correctly you have a stiff front sway bar. Do you have a matching rear sway bar as well. If your car has too much front sway bar it will lose grip over bumps and straight line breaking. And it will be more apt to push during cornering (understeer).
If I remember correctly you have a stiff front sway bar. Do you have a matching rear sway bar as well. If your car has too much front sway bar it will lose grip over bumps and straight line breaking. And it will be more apt to push during cornering (understeer).
Also, this should help a bit with braking.
https://www.blowfishracing.com/brake...der-brace.html
If you don't get what you like from the G-Lock pads give Wendy a call at racebrakes.com and look into Raybestos. The ST45/43 setup I'm running seems pretty darn good. You can move up a level to the ST47/45's if you want to get a little more aggressive though I'm betting Wendy would recommend otherwise. Also, the pricing on Raybestos is based on the pad design and doesn't increase based on how aggressive the compound is.
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Joined: August 2, 2013
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From: Little north of Stuttgart, Germany
No kidding! That's a lot of twisties!
So all my videos are junk. All of them. You can see outside for 30s out of 20min of video each.




The 911 GT3 I faught hard to get a point by from sounds great, but you can't see it


My only hope is that my dad took something better. He was my pit crew and photographer. He rode for one sessions and hand filmed a few laps. I have to see what his footage looks like.
Last edited by 5.M0NSTER; May 30, 2016 at 01:15 PM.
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Joined: August 2, 2013
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From: Little north of Stuttgart, Germany
So check this out. I was looking through my data to try to quantify how much difference the new suspension setup made over last year on the same exact tires on the same track (for apples to apples comparison), and last year the max lateral G force I was able to pull was 1.12g.
Here is this year. Not bad at all.
Here is this year. Not bad at all.
I see you are using Track Addict too. Do you believe those G numbers? I have seen some crazy numbers so it made me wonder.
Also the GPS track shows me going off the track quite a bit. I have only done that once, I swear! Do you get good GPS tracks from it?
I do believe it gives good lap times, since the start/finish line should be fairly repeatable. I have some pretty good video from it also . . . gotta get some posted up on youtube so I can link here.
Here's one I posted on SCCA Track Night in America page, let's see if this works:
http://www.tracknightinamerica.com/videos/2027654
Also the GPS track shows me going off the track quite a bit. I have only done that once, I swear! Do you get good GPS tracks from it?
I do believe it gives good lap times, since the start/finish line should be fairly repeatable. I have some pretty good video from it also . . . gotta get some posted up on youtube so I can link here.
Here's one I posted on SCCA Track Night in America page, let's see if this works:
http://www.tracknightinamerica.com/videos/2027654
Last edited by Bert; May 30, 2016 at 08:23 PM.
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Joined: August 2, 2013
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From: Little north of Stuttgart, Germany
Hey Bert, for peak numbers, yes, I believe it. I work in the auto industry on vehicle dynamics software and our instrumentation will spit out similar peak numbers. The thing to remember is that it's a peak. It could last as short as 20ms.
Of course we then gradient limit, kalman filter and average the **** out of it for use of the vehicle dynamics controllers. If anything there may be a few % gain error, but not an offset. As you can see in a straight line it gave me 0.0g. Gain of a few % is likely due to mount deflection for example. But at least my comparison is all apples to apples. The only difference is literally the suspension. Mount, mounting location, phone, tires all the same.
I wish Track Addict would give you max sustained G for 750ms or so. That would be cool!
I also think the the start finish line is pretty solid. At a high speed track 5m accuracy is good to 1/20s.
That looked like fun! You line was awesome until that GT350 blew by. Then all caution and expertise goes out the window trying to catch it. Been there too many times
Of course we then gradient limit, kalman filter and average the **** out of it for use of the vehicle dynamics controllers. If anything there may be a few % gain error, but not an offset. As you can see in a straight line it gave me 0.0g. Gain of a few % is likely due to mount deflection for example. But at least my comparison is all apples to apples. The only difference is literally the suspension. Mount, mounting location, phone, tires all the same.
I wish Track Addict would give you max sustained G for 750ms or so. That would be cool!
I also think the the start finish line is pretty solid. At a high speed track 5m accuracy is good to 1/20s.
That looked like fun! You line was awesome until that GT350 blew by. Then all caution and expertise goes out the window trying to catch it. Been there too many times
Last edited by 5.M0NSTER; May 30, 2016 at 08:47 PM.
So check this out. I was looking through my data to try to quantify how much difference the new suspension setup made over last year on the same exact tires on the same track (for apples to apples comparison), and last year the max lateral G force I was able to pull was 1.12g.
Here is this year. Not bad at all.
Here is this year. Not bad at all.
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Banned




Joined: August 2, 2013
Posts: 3,090
Likes: 254
From: Little north of Stuttgart, Germany
Ha! If I ever get R comps than yes. But for now it's good to see improvement while having these still on the car.
Next season I want to try this again with RE71Rs.
Next season I want to try this again with RE71Rs.




