Its been a while since I've done "serious" racing. I've done most of my racing at a club that's very new and while we get a far bit of track time, it's all pretty laid back and no overly serious. I decided it was time to gauge where I was with my car setup etc.
WCMRC are the other outdoor club in Perth racing F1 so I decided to make the 45km trip. Its a track that's been around a fair while, starting as a nitro track before houses started to encroach on it. The electric club took it over in 2010 and have been getting it back up to a top quality facility, hosting the Australian Titles in 2011. The club offers most current electric classes but on the day it was F1, VTA, Mini, Modified and 1/8 Electric. I had intended to run only F1 but due to lack of numbers I offered to run Mini as well. This stretched my battery supply to the limit because I had decided in advance to not take my charging gear with me.
Built in the late 80's, it doesn't appear the surface has ever changed much. The electric club appears to have resorted to using "tennis court" paint to revitalise the surface and increase the grip level. This is quite common around tracks in Australia that have the money to do so. The only real downside I've observed is that, if it rains, it can take quite a while to dry. The track also has quite a bit of elevation change.
After setting up I quickly hit the track for some practice. Now we have to remember I've done most of my recent running on a fairly low grip track, so it was almost a shock to feel the amount of grip available. Thankfully the base setup I have been working on proved workable from the start and I could focus on learning the track for the first run. 2nd run was more learning but I was playing with radio settings to increase my steering rate and reduce brakes. I didn't feel there was much point in changing any car settings until I had a comparison against other cars.
The club uses staggered start qualifying so its all against the clock. I made a dreadful start and ended up off the track. The grip level and my diff settings weren't quite in sync (this carried on all day to be honest) but once back on the track I was able to run competitive laps times, working myself back to 3rd qualifier for that heat. Compared to the regular runners I could see a couple of places I was losing time to them. Most obvious was the S section after the banked first corner around until the entry to the back straight. Through this section the car was slow to change direction through the S section and then it under-steered through the next section onto the back straight. I realised watching other races that the under-steer was, in part, due to the line I was taking, but the rest was all car set-up.
I tend to find running more than one car drastically affects the amount of time I can devote to car set up. I tend to resort to simple and obvious changes, which can sometimes make too drastic a change. In this case the simplest and most obvious change to the car which was a change of front tyre compound. I changed from Shizimu F1 to F3, however this totally destroyed the balance at low speed. Reducing the steering rate made a slight improvement but I decided after a half dozen laps to pull in and make sure I didn't cause an incident by spinning out in front of someone else. Annoyingly I set my fastest single lap of the day with this set up but it wasn't drivable over a race distance.
I qualified 4th overall despite dropping out of 2nd heat. Finals were normal grid starts. For the first final I had returned to the original tyre combination but made a castor change. Wrongly as it turned out. This was also the first time I had a really good indication of just how much my diff was slipping, as I was barely able to hold onto 4th as the race started. The race was pretty uneventful which wasn't really surprising as I was still learning the best lines around the track. The car was still slow to transition but was a little improved as far as under-steer was concerned though I think this was more because of my cranking up of the dual rate on the steering again.
The only change I made was to tighten the diff a little but at the start it still slipped far to much. This race was a little slower over all but I couldn't pinpoint any one reason. I hadn't made any significant changes so I wasn't expecting much, but I did manage a 3rd place.
A quick inspection turned up a very gritty diff so any other changes were forgotten to do a diff rebuild. One thing about racing in WA is the sand. Everything is built on sand and it tends to get into everything. I'm using a 3Racing out-tuned diff and this uses a similar thrust bearing combination as the F104 "Pro" diff, except it uses an alloy spacer instead of thrust washers. In practice I am suspecting this reduces bearing life and I think in this occurrence this was the problem. I didn't have a replacement so rebuilding the rest of the diff made little improvement.
I had a good first lap but that was followed by 2 dreadful laps and that put pay to any decent result. Luckily everyone seemed to be having an off race so I came back to 4th by race end. It was interesting to note that even the cars that didn't have any real problems were a lap slower than early in the day. I think the track was getting slicker as the track became more shaded.