Tuesday, July 3, 2018

New Heights, and New DIY

Once again, I've been slacking on the blogging, but as you will see on the standings page, the season has been progressing, and I've got a co-driver who's giving me some solid competition. The first few events were Freezing, Soaked and Soaked, so I pretty much lacked anything inspiring to blog about anyway. I went to the new Jersy Pro Solo, and had not really found my stride after missing most of 2017 in my car and getting almost nothing but rain events in the early season. I just wasn't getting slip angle like I should, and I was quite dirty, hitting cones or red-lighting on many of my runs as well. As will happen at the national level, if you aren't in top form you're at the bottom of the standings...

Some how I didn't feel eager to write about that either...

However, the weather improved, and satisfactory driving has finally come to pass. I've now managed to regain my prior level of driving from 2016, and in event #5, I finally found a new high point. One of the tough things about evaluating one's performance in autocross is that all measures are relative and the reference point is constantly in motion. To make a sane evaluation one has to make some assumptions. My first assumption is that the top drivers in our region are not getting slower. Given our region's consistent 6-7 national champions the last 3 years this seems reasonable.

While I'm comfortable saying that the top of the heap is still at a high altitude, there are some other things that clearly have changed. Firstly our region has had a buble of talented drivers mature in the last 2 years. I'd not want to argue that any of them have really pushed the top of the pax standings up yet in the way that Billy Davis did in 2015 and 2017, but they have definitely crowded the top. In 2016 I had 3 events where I was 1.5s off top pax, which resulted in 15th, 10th and 15th in overall pax. This year at the last 2 events, 1.5s from top pax is worth 20th and 19th... So making the top 10 or top 20 is significantly harder than it was 2 years ago.

Secondly, pax for the SSM class has been hit harder than any others besides AM, BM and CSP. BM/CSP and SSM are all almost a full percentage point harder than 2016 relative to the other classes. This translates into about .44 seconds tougher pax on a 60 second (raw) course. I've made a spread sheet here that shows that while all pax factors (other than AM) went down, the average pax factor went down much slower for SSM. This probably has something to do with the last 3 champions Thorne, Glagola and Wilcox all hanging out in the top of pax at far too many national events...

With that in mind, the 20th in pax result that had me 1.5 seconds off of top pax in event 5 Looks a lot like what used to get a top 10 in 2016. And my 2.3 seconds off of top pax in event 6 looks a lot like a top 20 in 2016 even though it now shows as 30th. Kudos to my co-driver Daryl, who kept the car in the top 20 at event 6 with his 19th in pax. For 2 events running my car has been 2nd fastest car with doors. Here's a video of my 2nd fastest run from event 5, which is probably faster everywhere except the start where I forget to shift like an idiot... Sadly I didn't remember to turn on the camera for the fastest run.


Additionally, I've also done some more maintenance/improvement on the car. Another factor in my bad results at the New Jersey Pro solo was epic levels of wheel hop on my launches on day 2 when the rubber was creating a lot more traction. A lot of exhaust bounce had also been noted at Devens, and the result was too much for my front motor mount to take.



The alignment was checked and it was almost 6mm toe in, probably due to bushing migration. Soft bushings, lots of toe-in and enormous race tires are a recipe for massive wheel hop. There was only one conclusion, tired old plastic/rubber A-arm bushings had to go. I replaced them with Monoball metal/teflon spherical bearings from Inokinetic. Since this seemed like an interesting job, I also made a DIY video for it:


The results? FABULOUS. Both me and my co-driver Daryl noticed improvement in the predictability of the back end when rotating it around a corner, and improvement in braking. The first was expected and the second was a nice surprise. My rear suspension had probably become so floppy that the ABS probably triggered earlier. I also suspect this slop negated all rear braking once it triggered by wagging the A-arms back and forth with the ABS pulses. The start for this course did not lend itself to hard launches, and due to the late date of it's discovery I had to continue with the above mount after Ryan welded the split for me. Next event we will be doing full launches if the course allows it and then I expect to find that the wheel hop has also improved.