GTI-S Autocross: 26mm H&R RSB

[aroundomaha]

A while back I posted a Youtube of my first autocross in over 30 years. I had fun but wasn't remotely close to competitive. Many thanks for everyone for all the discussion and good advice. I couldn't take all of it (late in the season), but did upgrade to an H&R 26mm rear sway bar last week.

The result & review? On my otherwise stock car running the OEM Bridgestone all-season tires I give the result two thumbs up. For the first time I was faster when turning off the traction controls and driving at the limit of the Potenza RE97AS tires. I was able to place second in G Street, less than a second behind a Mazdaspeed3 with better tires.

Here is a video of my quickest run
https://youtu.be/2fR2LLifIC0

The net result was I no longer plow into corners and can find the slip angle to work with it. I can turn off the traction control and work with the car/tire combination. Now I really do need better tires, but that is for next season's autocross events. Bottom line is I'm 100% happy at making the RSB my first upgrade to my GTI.

Anyone else using a QStarz GPS and MX+ OBD sensor with TrackAddict and finding it an unreliable pain in the ass? Seemed like one or the other was always falling out of sync via bluetooth. I talked with someone running SoloStorm and he had similar issues.

Many thanks to Alex & crew at Omaha's SLine Motor Sports for getting me in for a late Friday appointment to install the RSB.

Here is a shot of the H&R installed.

 

[GTIfan99]

I autocrossed a non-PP car last year and moved to a PP car this year. Your major challenge will be keeping front tire temps under control. All that heat generated by the xds goes straight to the wheels and tires. Spray early, spray often when you move to 200tw tires.

I was able to FTD pax with a non PP car, so it can be fast, you just heat cycle tires out quicker.

I'm in for hearing what GPS people have had good luck with, as I'm looking to get one soon too.

PM me if you want alignment advice.

 

[aroundomaha]

I autocrossed a non-PP car last year and moved to a PP car this year. Your major challenge will be keeping front tire temps under control. All that heat generated by the xds goes straight to the wheels and tires. Spray early, spray often when you move to 200tw tires.

I was able to FTD pax with a non PP car, so it can be fast, you just heat cycle tires out quicker.

I'm in for hearing what GPS people have had good luck with, as I'm looking to get one soon too.

PM me if you want alignment advice.

Does the XDS kick in even when you cycle traction control off? I was thinking turning that off also did away with the brake vectoring (or whatever VW calls it).

For data/GPS I went with TrackAddict, OBDLink MX+, and QStarz Q818XT 10 HZ. My problem is that the GPS and OBD bluetooth would often not be in sync at the same time. The GPS would go back to "good" at 1 or 2 hertz and low accuracy, then after getting that back the MX+ would suddenly not come back. I'm using an Android phone dedicated to just doing this as that seemed to be what people recommended.

It was such a distraction that I shut it all off during day 1 while I was learning the course. The video is sort of nice/fun but I wanted to compare results between runs.

Here is an example from the same day, same setup but with wildly inconsistent results.

 

[AZStig]

I had pretty decent results using Harry's lap timer for comparing my autocross runs.

I am curios to see how everyone sets up their cars. i have not run this car yet, still running AS in my 981 Cayman. Managed to win the 4 race series running in SS in 2018. But was glad this car got moved to AS.

When I started autocross, I was running 2013 BRZ. First event was a showroom set up car.
2nd event had RPF1 wheels, with the original Rivals. Tires made a huge difference.

next season I added a stiffer front sway bar, the car had nearly no body roll.

Eventually, I added koni struts, and put as much front negative camber as possible on stock geometry set up. I loved that car.

anyhow, sorry this is not about the GTI, but how it was fun to improve the car and notice the difference.

 

[GTIfan99]

XDS is the fake LSD and cant be turned off unless you unplug the ABS fuse, which is the only legal way to defeat it, but the brakes are very touchy without ABS on this car on the broken asphalt we use, or can be disabled with OBD11, which isn't legal for GS.

As far as setup, 1/16 in toe out front, 1/16th toe in rear, -1.8 camber rear, 26mm sway worked well on both my cars. I originally zeroed out rear toe but the car was way too loose..

I'll have to do some research on GPS that work well with Track Addict and get one soon. The 1hz receiver in the phone just doesn't cut it.

 

[aroundomaha]

XDS is the fake LSD and can be turned off unless you unplug the ABS fuse, which is the only legal way to defeat it, but the brakes are very touchy without ABS on this car on the broken asphalt we use, or can be disabled with OBD11, which isn't legal for GS.

As far as setup, 1/16 in toe out front, 1/16th toe in rear, -1.8 camber rear, 26mm sway worked well on both my cars. I originally zeroed out rear toe but the car was way too loose..

I'll have to do some research on GPS that work well with Track Addict and get one soon. The 1hz receiver in the phone just doesn't cut it.

I won't fiddle with the electronic braking system, but would love to cut out XDS+ (like SMokey Bear said "only you can prevent brake fires" Maybe it doesn't matter as much for 40 to 90 second autocross runs but I'm guessing it will wear the brakes quickly even if they don't catch fire.

The map above was via TrackAddict and the QStarz 818. It was wildly inaccurate which could mean I need to learn how to set it up and use it, or that it doesn't work as advertised. I was connecting it to a Samsung Note 8, so it isn't a junk phone. I had better results at a previous autocross using the built in GPS. Something to work on over the Winter I guess.

 

[GTIfan99]

I won't fiddle with the electronic braking system, but would love to cut out XDS+ (like SMokey Bear said "only you can prevent brake fires" Maybe it doesn't matter as much for 40 to 90 second autocross runs but I'm guessing it will wear the brakes quickly even if they don't catch fire.

The map above was via TrackAddict and the QStarz 818. It was wildly inaccurate which could mean I need to learn how to set it up and use it, or that it doesn't work as advertised. I was connecting it to a Samsung Note 8, so it isn't a junk phone. I had better results at a previous autocross using the built in GPS. Something to work on over the Winter I guess.

Brake fade or wear weren't really an issue for autocross. Overheating the front tires to levels I've never seen in 35 years of autocrossing was. That increases wear and heat cycles them out quickly. I'd kill it with OBD11 and call it done unless you're going to run national events.