Autocross results - April 23

[mrondeau]

The Harry's Laptimer for the iPhone is pretty easy to set up. Most of the tracks we run, (SOW, Auto Club Speedway, Buttonwilow, Chuckwalla, etc.) are already available for free download. For AX, you have to set the start and finish manually. You can also set intermediate points as well. I usually set them up by section during the track walk. To get the map view, just export the data from that lap via your phones email to your email address and then open it up with Google Earth. If you select it, the app will also video tape the lap using the same sensors to start and stop the video. For $14 it's a cheap and easy solution. As Jad says, it's not a real data acquisition system, but it will give you some idea of what you're doing out there and where you may be gaining (or losing) time.

The iPhone app seems to work a little better than the Android one right now, but that will probably change as more apps become available for the android phones. YMMV.

[bbrand]

Martin,
Your telemetry data is really fascinating, because I compared to my Harry's Lap Timer TTOD lap, and you are faster (sometimes significantly) on just about every marker - but I still finished several seconds ahead. When I get home later, I'll post the screen shots. Maybe it's the external GPS accuracy?
Bob

[martinreinhardt]

Bob,

Congrats on your excellent run. You didn't forget how to drive while building your new car I can't wait to compare with your data.

We were suffering from exit oversteer and could not put the power down. My best lap of the day was a 1:14.25 after the track changed, but could not repeat it during the timed runs. Maybe the TomTom iPhone adapter improved the accuracy, but I am not sure it makes that much of a difference. You probably were able to keep a more constant speed thru out the course due to better grip and lighter car. Our car will be setup differently again next time, so we will see if it works better.

BTW I noticed the same thing with my Formula car where I am usually 10-15 seconds faster per lap than the fastest Porsche's on most race tracks, but yet the straight line top speeds in the F3 are sometimes slower.

[bbrand]

Run 2 was TTOD
Run 3 was a spin when I oversteered onto last straight. Drift around the bunny ears too — not on purpose. Car stayed pretty straight though - that time.

It says I'm slower than you just about everywhere. It says I'm slower than Mark just about everywhere!




Here is a video of the two runs:
http://youtu.be/pI0aF31cagU

Bonus video:
I tried overlaying the Harry's Lap Timer telemetry on my GoPro video, but my synchronization was off by half a second or so.
http://youtu.be/PRAjm1j3de8

Select HD for best quality.

[martinreinhardt]

Thanks for posting the cool videos and interesting data to compare with. I can see from your video that you do have more grip and probably had some reserve to go even faster if you needed to.

[bbrand]

Yes, apparently I can go more than 47mph, but not as much as 51mph onto the last straight

[pdy]

We will be back with fresher tires
The plan is to be down for the next SD event on Sat. and then attend the SCCA event on Sunday. Stickers will be ordered this week

Oh.. thanks for not busting us on the exhaust.

B

I know Butch was loudish too, so I will install my stock muffler, not the "sport" muffler.

BRAD & CARL: Besides exhaust police, be aware that tech/safety monitoring will be active as well. You should study rules section XIII.K regarding tires.

[JERRY B]

All parts of the tire which normally contact the road must be covered by the fender when measured from a vertical drop from the fender edge through the center line of the wheel.

[Kim Crosser]

If Steve G isn't using his 914 "oil barrel" fender flares any more, maybe Brad and Carl can bolt those on...

Or, if you inflate them enough (200 psi?), the parts that "... normally contact the road ..." might wind up being covered by the fenders.

[Brad Roberts]

Fenders:

I installed these to "keep the peace" on another Boxster that people complained about.. I'm sure I can paint and make them look nice on Carl's Boxster (lame)




I deleted a long rant... These fiberglass fender flares I'll install solve NOTHING. They won't make the car safer, it won't keep the steel fender from **possibly** cutting a tire

[Mmagus]

Sorry you even felt you had to rant and erase. No complaints here. The rules are fairly straightforward well at least they seem that way to me As an AX-Chair if I notice what seemed to be something out of the norm its part of my responsibility to inquire and encourage folks to follow them. Right?

[Brad Roberts]

and people wonder why car count is down and SD region has to allow "non-Porsches" to run to fill the grid?

It starts with the rules.

I understand you are doing your job. I'll do mine and comply

Golden Gate region is thinking of doing the same thing with their rules.


B

[Jad]

Brad,

If it makes you feel any better, my understanding is the rule has nothing to do about cutting tires it is an insurance thing. We are NOT allowed to run open wheel cars, no karts, no Indy cars, no F1 cars no matter how safe they are. Only closed? wheel cars as defined as having their tires completely enclosed by body work.

Those silly little flairs may actually help in a wheel to wheel contact in keeping the cars from going airborne aka Mark Weber, but whatever the reason they have to define open/closed wheel somehow and their definition seems reasonable to me to avoid some pretty lame fenders being attached to open wheel cars that claim to be closed .

Though you may want to be careful as they can also refuse to let you run if they feel your car is unsafe if they think the steel fender may cut the tire even if it is covered by a flare!!!

[Kim Crosser]

Also - the tire/fender rule is not a San Diego rule. It is a Zone 8 Competition rule, and thus applies to all events within Zone 8. In various places in the Competition rules it mentions increasing wheel and tire sizes, but each section also includes the explicit caveat - "...however, Section XIII Part K requires that the tire must be covered by the fender."

You could certainly lobby Zone 8 to change the rule to allow stock cars with factory fenders to have tires that extend some reasonable distance beyond the fender. Until that, your extended wheels/tires would be illegal for any Zone 8 event.