ASK THE COACH
#1516
Race Car
^ yes, thanks VR - agreed, I noticed that.
Left hand side isn't my fastest, just a typical lap.
The right side 1.17.3 is .7 better than any previous lap I've done ...
And on old rubber (HC 12-14) ...
So I'm trying to identify/clarify what worked so much better than what I typically do
Left hand side isn't my fastest, just a typical lap.
The right side 1.17.3 is .7 better than any previous lap I've done ...
And on old rubber (HC 12-14) ...
So I'm trying to identify/clarify what worked so much better than what I typically do
#1517
Rennlist Member
Thread Starter
Not sure, but do not underestimate the elapsed time effects of subtly backing off in a couple of corners due to traffic. A couple of tenths here and there, and presto! 0.7 sec behind!
#1518
Bench march for braking
Ok so last week I sat in on Peter's trackmate lesson. Peter you said that as a goal we should be able to brake at about 90% of our sustainable lat g load? I seem to be able to hold about 1.2 lat g and most times can only brake about .85 g before locking up the front tires. I have a manual brake bias with it set all the way to the rear side adjustment. the car is a 90 carrera with 993 big reds up front and the original 4pot cailpers in the back. Same set up Kai runs and running pagid yellows F pagid black R. 235 front tire 275 rear tire Nitto nt01 rcomp) compresion on damper set 3 click off full stiff front and full stiff rear 600lbf 800lbr spring rear anti roll set full stiff front set in the middle . Is the car set up wrong or what am i doing wrong? in certain spots like up hill brake zone etc i can brake at about 1.1 g before wanting to flat spot my tire. With that said I i am turning low 1:42s at laguna seca consistently with a big microphone avoidence muffler hanging off the back of the car 90db days .. will try to get screen shot of the data that I am learning to use thanks to Peter!!
Sorry for long ramble I am just hoping to learn how to brake later harder as Peter suggest but I seem to upset the car if I try that and tend lock up fronts that way
Sorry for long ramble I am just hoping to learn how to brake later harder as Peter suggest but I seem to upset the car if I try that and tend lock up fronts that way
#1520
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Add before I run out.
With that brake setup, without the bias adjustment, or with it set to full bias to the rear, you are VERY biased to the rear. Way too much so actually and you would be swapping ends often.
I wonder if you don't have too much front bias in and therefore are not taking full advantage of the setup you have.
(I vary btw. mid setting and one click more front bias depending on the track and still carry a LOT of rear bias)
With that brake setup, without the bias adjustment, or with it set to full bias to the rear, you are VERY biased to the rear. Way too much so actually and you would be swapping ends often.
I wonder if you don't have too much front bias in and therefore are not taking full advantage of the setup you have.
(I vary btw. mid setting and one click more front bias depending on the track and still carry a LOT of rear bias)
#1521
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The car should not get in your way of trying to brake at maximum retardation.
Test this in a straight, level section of the track without anyone behind you and not entering a corner. This is just a test to generate braking force data.
First, squeeze on the brakes to eliminate the possibility that you are inadvertently slamming on the brakes. Then, push harder until the fronts begin to lock or the rear gets loosy-goosy underneath you. Squeeze gently enough to modulate, or come back off the brake, to NOT lock up, but be on the threshold of doing so.
Methinks the car is not right... But you need to test.
Under no circumstances, in a straight line and on level ground, should your car NOT be able to generate -.95 to -1.0 g...
The 911 is one of the finest platforms for powerful braking there is. Period. Even if you choose not to use all of the capability, you need to know that it is there. And it should be.
I have driven many street cars that were unmodified that stop better than modded street cars or race cars...
Test this in a straight, level section of the track without anyone behind you and not entering a corner. This is just a test to generate braking force data.
First, squeeze on the brakes to eliminate the possibility that you are inadvertently slamming on the brakes. Then, push harder until the fronts begin to lock or the rear gets loosy-goosy underneath you. Squeeze gently enough to modulate, or come back off the brake, to NOT lock up, but be on the threshold of doing so.
Methinks the car is not right... But you need to test.
Under no circumstances, in a straight line and on level ground, should your car NOT be able to generate -.95 to -1.0 g...
The 911 is one of the finest platforms for powerful braking there is. Period. Even if you choose not to use all of the capability, you need to know that it is there. And it should be.
I have driven many street cars that were unmodified that stop better than modded street cars or race cars...
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-Peter Krause
www.peterkrause.net
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"Combining the Art and Science of Driving Fast!"
Specializing in Professional, Private Driver Performance Evaluation and Optimization
Consultation Available Remotely and at VIRginia International Raceway
-Peter Krause
www.peterkrause.net
www.gofasternow.com
"Combining the Art and Science of Driving Fast!"
Specializing in Professional, Private Driver Performance Evaluation and Optimization
Consultation Available Remotely and at VIRginia International Raceway
Last edited by ProCoach; 11-28-2013 at 11:48 AM.
#1522
Rennlist Member
Thread Starter
Ok so last week I sat in on Peter's trackmate lesson. Peter you said that as a goal we should be able to brake at about 90% of our sustainable lat g load? I seem to be able to hold about 1.2 lat g and most times can only brake about .85 g before locking up the front tires.
I have a manual brake bias with it set all the way to the rear side adjustment.
I have a manual brake bias with it set all the way to the rear side adjustment.
Please explain the part in bold: "rear side adjustment"???
#1523
thank you all that have responded. Kai and VR the brake bias adjuster is set to put more brake to the rear and it is not squirmy at the rear at all. At Peter thank you for the testing idea our season just finished this week so will most like not be back on track until FEB but have local air strip I can try to go do the test on? So sounds like I need more data for now I will work on obtaining that. If I can figure out how to screen shot a lap from Laguna last week I will put that up. You guys are all the best Happy Thanks Giving
#1524
Ok so let the teaching begin. here is the data from Laguna Seca last week. Here is my thoughts going into 2 it is down hill and slight direction change making inside front want to lock easier, the "soft brake" areas are were I need help most of these spot I am trying to set the nose for turn in in med speed corners. Is this where I should be braking later and harder? I also know I am "double braking" for turn 8 I am to scared and not sure I could make it if I waited until after the crest going into it (car light) the rest of the harder brake zones I seem to be stuck around .85 going into 11 I seem to get to .9 .. I am ready to learn and hoping to sort out if I need to work on my braking system on the car along with how I can do better over the winter break again all of you that contribute are amazing and I am very thankful
#1525
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What level of experience do you have in your driving career? You are a little peaky in your braking - you build pressure pretty well, but get off them pretty quick instead of trailing off nicely.
#1526
@ Matt I have only done 2.5 years of DE/TT with local PCA and a few extra days probably 17 days a year? for a total of maybe 40 days on track with only 4-5 20 min sessions a day.
#1527
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Because of my **** driving and inability to break out of my rut. I took Peter's TM webinar. Very good job, Peter. Thanks. Now I am trying to learn how to use the software and what it means. I bought Chris Brown's book about Squiggly Lines. (Peter's recommended reading list) Now I'm really depressed.
I hope the optimism I left the seminar with regarding the likelihood of finding a patch to improvement is more than a dream.
Reading the TM manual, it says that each segment will be color coded and show up in the Graphs. It notes "Highlight". I guess I'm not doing the Highlight part since they don't show up in mine. What is the trick? I see them in tahoelife's.
Thanks
I hope the optimism I left the seminar with regarding the likelihood of finding a patch to improvement is more than a dream.
Reading the TM manual, it says that each segment will be color coded and show up in the Graphs. It notes "Highlight". I guess I'm not doing the Highlight part since they don't show up in mine. What is the trick? I see them in tahoelife's.
Thanks
#1528
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Randy. under Setup for the run you want to look at, click Track Map on the top left of the dialog box. When the Track Map shows up, resize it to where you want it on the screen and click "Segment Tools" to open the dialog box and place the segment markers on the map. I usually click Auto Create Segments, then move them to track out points from each corner. THEN, the colored markers will be shown on the map and on your graph.
If you want to email me a file, I'd be glad to take a look. (offer good for webinar attendees only)
Don't let "analysis paralysis" get to you! I'll give you two or three things to work on.
If you want to email me a file, I'd be glad to take a look. (offer good for webinar attendees only)
Don't let "analysis paralysis" get to you! I'll give you two or three things to work on.
#1529
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Randy. under Setup for the run you want to look at, click Track Map on the top left of the dialog box. When the Track Map shows up, resize it to where you want it on the screen and click "Segment Tools" to open the dialog box and place the segment markers on the map. I usually click Auto Create Segments, then move them to track out points from each corner. THEN, the colored markers will be shown on the map and on your graph.
If you want to email me a file, I'd be glad to take a look. (offer good for webinar attendees only)
Don't let "analysis paralysis" get to you! I'll give you two or three things to work on.
If you want to email me a file, I'd be glad to take a look. (offer good for webinar attendees only)
Don't let "analysis paralysis" get to you! I'll give you two or three things to work on.
I will search through my files tomorrow for a Rd Atl file to send. I will digest what you suggest, finish the book, develop a basic understanding of DATA, then we will dig in deeper together. I will have to ask some questions here to get the basics right.
Thanks, Peter.
#1530
Nordschleife Master
Do you still have the file I sent you on the day of? If yes, I'd love to get "two or three things to work on".