Go Back   986 Forum - for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Boxster Racing Forum

Reply
 
LinkBack Thread Tools Display Modes
Old 06-04-2012, 10:44 PM   #1
Registered User
 
Join Date: Jul 2006
Location: san jose
Posts: 225
Autocross lap timer

2 question for you seasoned AX folks:

1. How come there's only one timer at the end of the course ?

I was reviewing some of my videos from my last AX and I realized that while my time dropped down lap after lap ( most of the time anyways ) simply from learning and getting used to the course, not from any major improvement in skill. Technique improvement ( if any at all ) have been slow. IMO, part of the problem is the general lack of granular data in an AX environment.

Its hard to train yourself to be 'faster' when you don't know what you're doing right / wrong. Instructor help to a degree, but its still up to you to figure it out. For me, data makes figuring things out much easier.

For example, with AX there's no way to know things like .. last lap I ran .25 second faster than my best previous time because I gained .5 second in turn 2 but lost .25 second on turn 5 .. next lap if I do the same thing on turn 2 but change it up for turn 5, I should be even faster.

Instead, I only get a time slip at the end of each run which only gives a very generic idea of my overall performance.

IMO, if instead of just the one timer at the finish line, setup more timer so we can get a time for each 'section' of the course.

Has something like this ever been done ? If not, is the problem cost ? Unavailable technology ? Too much hassle to setup ?

2. I'm considering a GPS lap timer like the Ultra XT GPX to solve this issue for me. Its pricey but I'll use it for my bike track days also .. so I'll save the $40 rental fee .. and it should pay for itself in 20 days .. LOL

Anyone have experience with the GPX or a something else that works for this purpose ?

Thanks!

Last edited by vijen6; 06-04-2012 at 10:51 PM.
vijen6 is offline   Reply With Quote
Old 06-05-2012, 03:56 AM   #2
Rennzenn
 
j.fro's Avatar
 
Join Date: Feb 2005
Location: Virginia
Posts: 1,355
Garage
Using intermediate timers on AX courses would be interesting, but they would get destroyed! When drivers are really pushing it, they can go off course just about anywhere. AX course designers are very conscious of finish-line design, making it so that the timers are less likely to get nailed by a wayward driver, but it happens anyway. When that happens, it takes a while to get things re-set with the spare timers...and they are about $200 each, which is billed to the schmuck who took it out. And that brings up another point...most AX organizations run on a pretty tight budget. Cost for a split timer is just too much.

So here's my thoughts on using a data logger...
I tried using LogBox on my iPhone, but it really didn't teach me anything that was usable at the next event. Even when you're at the same site event after event, every course is so different. It's impossible to review a section and then try it again...once the event is over, that section is gone! Plus, I find that when I think too much during a run, I'm more likely to over/under drive those sections.
For me, simply driving lots and "Use the Force, Luke!" is the most effective approach. I try yo get at least two, if not three events per month. At the beginning of the year I will look at the calendars from different organizations and decide which will be my "priority" races and which will be my "prep" races. I try to arrange my schedule so that there's a "prep" race one week before a "priority". That really helps to tune me in to the limits of the car.
j.fro is offline   Reply With Quote
Old 06-05-2012, 06:45 AM   #3
Track rat
 
Topless's Avatar
 
Join Date: Nov 2006
Location: Cucamonga CA
Posts: 3,643
Garage
You could get a lap timer like Harry's with a 5hz receiver and get lots of data but I agree there is limited value in it for AX. Get in the right seat with the fast guys and watch how they do it. Get an instructor in your car and focus on one section at a time. Seat time is 100X more valuable than data. I like to use the fastest guy in my class as a yardstick for possible performance. On big tracks, I use the lap record in class as my yardstick.
__________________
2009 Cayman 2.9L PDK (with a few tweaks)
PCA-GPX Chief Driving Instructor

Last edited by Topless; 06-05-2012 at 06:49 AM.
Topless is offline   Reply With Quote
Old 06-05-2012, 11:46 AM   #4
Registered User
 
Join Date: Jul 2006
Location: san jose
Posts: 225
Thanks Topless, J.Fro.

Its not about getting data to improve for next time since the course will be different so your data is much less useful. Its about getting instant data after the run so you can analyze during that 5 min time gap while waiting for your next go around.

I 100% agree that getting in the right seat with the fast guys is definitely at the very least an eye opener to see how fast the car can actually go, where the limits are and what are the best line for each corner are ect ect.

However, IMO, both good granular data and instructor seat time are good student aid. In fact they're best together.

For example if I did a lap with the instructor driving, followed by a lap that I drive. Then looking at the data for both lap while we're waiting for the next go, it would let me quickly identify the parts that needs the most improvement.

Observation like "hey, I'm 18 second off the instructor's time .. but that's because the instructor completed section 3 in 25 seconds and I completed it in 40 second .. I'm losing 15 second alone there .. that's probably from me slowing down too much before the slalom" is much more useful when trying to learn as compared to "dang I'm 18 second off the instructor's time .. he must be really good .. I'll try harder next time on the whole course".

With A/X, you don't get as many runs around a course as you do with a big track so quick accurate observation matters even more. I'll look into that Harry's timer you recommended.
vijen6 is offline   Reply With Quote
Old 06-05-2012, 12:29 PM   #5
Registered User
 
jaykay's Avatar
 
Join Date: Sep 2009
Location: toronto
Posts: 2,277
Instructors I have have put me in their cars to show me what is possible and where the outside of the envelope is....ahhh one trip in a Cayman R cutting through traffic on near slicks had me screaming inside my head for the first few laps (Mosport)....it left me wondering what the heck his race car would be like...and hey this dude has got Hans on should I be concerned....hahaha

Basically he was trying to show me how slow I was and where things need to go for progression

Look, feel, and do
__________________
00 986 S....with a few tweaks
jaykay is offline   Reply With Quote
Old 06-05-2012, 12:33 PM   #6
Registered User
 
Join Date: Aug 2005
Location: Ohio
Posts: 380
Garage
I used a Qstarz 818xt GPS receiver combine with an old MOT smartphone running race chrono as a track lap timer and it provides great info about speeds/lap position on various parts of the course.

Auto-x courses are a lot smaller but this may provide some good data about how fast you're going at various spots on the course.

RaceChrono - The GPS Lap Timer
__________________
2013 Boxster S
2006 Boxster--sold
1999 Boxster--sold
MikenOH is offline   Reply With Quote
Old 06-05-2012, 02:41 PM   #7
Track rat
 
Topless's Avatar
 
Join Date: Nov 2006
Location: Cucamonga CA
Posts: 3,643
Garage
Quote:
Originally Posted by vijen6 View Post
For example if I did a lap with the instructor driving, followed by a lap that I drive. Then looking at the data for both lap while we're waiting for the next go, it would let me quickly identify the parts that needs the most improvement.

Observation like "hey, I'm 18 second off the instructor's time .. but that's because the instructor completed section 3 in 25 seconds and I completed it in 40 second .. I'm losing 15 second alone there .. that's probably from me slowing down too much before the slalom" is much more useful when trying to learn as compared to "dang I'm 18 second off the instructor's time .. he must be really good .. I'll try harder next time on the whole course".

With A/X, you don't get as many runs around a course as you do with a big track so quick accurate observation matters even more. I'll look into that Harry's timer you recommended.
Ok, if you are 18 sec. off your instructors time on a 60 sec. AX course... you might want to consider golf.

Seriously though, I use data loggers/lap timers and they are very valuable when you are beyond the basics and chasing that last 1/2 second on a track. I rarely set it up for AX. When I first started out six years ago I think it would have been TMI. With PCA-SDR you are not even allowed to have a lap timer in the car until you are Solo qualified. A handy track map, verbal instruction between runs, right seat time with an experienced instructor, and corner working tend to be the fastest way to learn AX in my experience. Feeling how the car moves from the right seat with a smooth driver is still very useful to me.

These are good gps laptimers/dataloggers when you are ready:
Welcome to Harry?s GPS LapTimer
RaceChrono - The GPS Lap Timer
__________________
2009 Cayman 2.9L PDK (with a few tweaks)
PCA-GPX Chief Driving Instructor
Topless is offline   Reply With Quote
Old 06-05-2012, 04:01 PM   #8
Registered User
 
Join Date: Jul 2006
Location: san jose
Posts: 225
LOL .. perhaps .. I remember my first PCA AX .. I put down a 68.xx something my first lap out .. the instructor driving trailer queen 914 was at 54.xx while talking to me almost the entire lap like he was just doing a Sunday grocery run. LOL.

By then it was too late to take up golf. After the first lap in the instructor's car I was already hooked.
vijen6 is offline   Reply With Quote
Old 06-06-2012, 09:53 PM   #9
Registered User
 
Join Date: Jul 2006
Location: san jose
Posts: 225
Looks like RaceChrono is the ticket. Found this review here ( Racechrono datalogger review - Technical Forum ) which was very helpful.

DL'ed their new Android 2.0 version and tested my 'lap time' walking the dogs tonight. Seemed to work great. I identified that the cause for my slowest lap were when I 'off course' for pooper scooper duty.

Will pick up a 5ghz external GPS and try this out at the next AX. Thanks again everyone for your advice. Hooray for more toys!
vijen6 is offline   Reply With Quote
Old 06-07-2012, 06:11 AM   #10
Registered User
 
Join Date: Jul 2011
Location: Albuquerque, NM
Posts: 56
Send a message via AIM to ABQautoxer
I've tried a lot of the timers/dataacq devices out there from the early days of the GeezCube to the latest thing which is an AiM Solo. I tried Harry's laptimer pro and there are enough quirks I'm selling my 5Hz receiver to another local who wants to play with it. You can create all the sectors you want later for analysis.

http://www.aim-sportline.com/pages/solo/index.htm

First, take an autocross school - its the best thing you can do when you are starting out before you learn bad habits that can take awhile to unlearn.

http://evoschool.com/

Second, take video and data and then try to do the same with someone else who is faster. It's a lot easier to analyze when you have data from someone else and if they are faster its even more useful IMO. If you opt for video, make sure you can see the driver and steering wheel otherwise its just for entertainment purposes.

Last but not least, I don't play with the data or video during the runs as I find it too distracting. I either analyze it after the event or if its a Pro Solo, between the morning and afternoon runs.

Last edited by ABQautoxer; 06-07-2012 at 06:20 AM.
ABQautoxer is offline   Reply With Quote
Old 06-07-2012, 08:50 AM   #11
Registered User
 
Join Date: Jul 2006
Location: san jose
Posts: 225
I really want to take the Evo School, but the surface of the parking lot where they have it in my area ( Golden Gate Fields ) is notoriously bad on tires.

I can't afford $250 for a day then another $1200 to replace my tires.

I'll just need to stick to PCA novice school for now. Took one last year, but this year wont be able to make it due to schedule conflict. By next year, I might have about 20 events under my belt so the novice classification might be a stretch. Just a super slow 'expert'. LOL.
vijen6 is offline   Reply With Quote
Old 06-07-2012, 09:18 AM   #12
Registered User
 
LAP1DOUG's Avatar
 
Join Date: Aug 2011
Location: USA
Posts: 407
I have used a smartphone app called Trackmaster that was pretty cheap and worked OK for sector times. I first walked the course with the software app running to identify the course and the sector breaks that you want to use. Obviously that first recorded time will be slowwwwww.

Our local SCCA region used to place several lap timers around the course, and post everyone's sector times. That was extremely helpful because then you could see where you were gaining or losing time compared to others in an apples to apples comparison. Too bad they stopped doing that when they appointed a new solo coordinator.
__________________
Kippis
LAP1DOUG is offline   Reply With Quote
Old 06-07-2012, 09:30 AM   #13
Registered User
 
Join Date: Jul 2011
Location: Albuquerque, NM
Posts: 56
Send a message via AIM to ABQautoxer
Quote:
Originally Posted by vijen6 View Post
I really want to take the Evo School, but the surface of the parking lot where they have it in my area ( Golden Gate Fields ) is notoriously bad on tires.

I can't afford $250 for a day then another $1200 to replace my tires.

I'll just need to stick to PCA novice school for now. Took one last year, but this year wont be able to make it due to schedule conflict. By next year, I might have about 20 events under my belt so the novice classification might be a stretch. Just a super slow 'expert'. LOL.
Do it on street tires would be my advice anyway. I did Phase 1 and Phase 2 on a set of star specs and the wear is really not too bad for a B Stock prep'd boxster.
ABQautoxer is offline   Reply With Quote
Old 06-07-2012, 09:58 AM   #14
Registered User
 
Join Date: Jul 2006
Location: san jose
Posts: 225
Quote:
Originally Posted by LAP1DOUG View Post
Our local SCCA region used to place several lap timers around the course, and post everyone's sector times. That was extremely helpful because then you could see where you were gaining or losing time compared to others in an apples to apples comparison. Too bad they stopped doing that when they appointed a new solo coordinator.
That's what I was talking about. Sector times where you can compare how you did on certain corners vs the fast guy. Apple to apple comparisons make it easier to identify the lowest hanging fruit. Too bad they stopped.
vijen6 is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 10:12 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page