- Schumacher MI5 - Ed Clark - Queensland State titles - Bayside - 27-28.09.2013 -



So, it's taken a while for me to get round to posting this up, but a few weeks back, we had our State titles here in Queensland, at the Bayside club. The track is outdoor asphalt, and the track has a combination of open and flowing sections, with a succession of tight hairpins at the end of the lap. It also has a fair amount of bumps, mainly in really inconvenient places, like heavy braking areas! All in all, it's a track that is very hard on the cars, but still a fun layout all the same.
As bit of extra info, all the running was done in mod, with the titles also using Ride REX34's as the control tyre... so they are the only tyres I've run so far with this car!

Given that I'd only switched to the Schuey a few weeks ago, I have felt a little on the back foot. However, the weekend previous, I got a chance to go testing for the day in conditions not disimmilar to the the actual weekend, and had ended up on what I felt was a pretty decent base setup, based closely on the Grainger WLRC setup, but with some changes to the shock setup and camber links to suit.

Friday of the states was set out for practise. I had a pretty big list of things I wanted to try, and also had a few new parts to put on. These included the rear suspension ball braces and revised ackerman plates, along with the previous team mods (cut arms, centre ball steering rack). Due to limits with time... I actually bolted on the mods before the start of the event, and then didn't take them off! As far as I can tell, the mods worked well. The revised ackerman plates certainly seemed to improve the linearity of the steering. Just digressing for a bit.. All the mod parts I made up myself out of some spare carbon I had lying around. With the ackerman plates, I made some up with a moved mounting hole. One set moved the hole in towards the centre 1mm, one set 2mm, and the last moved the hole 1mm in and backwards as well. I actually ended up only using the "1mm in" set, on the advise of Chris and Matt W. On the gauges, there is certainly a difference to the kit parts, with less ackerman angle, as shown by less inside wheel lock, and more outside, making the front inside tyre scrub less. I am keen to try out the other plates, but that will have to wait..

First off, ran through some spring changes, trying out Schuey Blues, Ride Green and Yellow. Ended up on the Schumacher Greens, as these gave the best compromise between corner speed and bump control. This was quite an interesting find, as my previous car (Serpent S411) needed a much softer spring to work well, normally ending up on Ride Yellows. I partly believe that it's to do with the flex of the car, in combination with the full size shocks.

The next parts I ran through were gear diff vs spool. Now Bayside always seems to favour the gear diff in the front. It's no faster than a spool, but is more consistent... and this proved no different. The spool just felt a little inconsistent to drive, and struggled to get through the centre of the hairpins.

Having worked with these options, I was really happy that I had a good consistent, safe, base setup to revert too if needed. The car was still lacking some mid-corner rotation, and having looked at the Euro's setup, I wanted to try a setup more similar to that. I started out with using no shims under the front suspension balls, and 0.5mm under the rear, whilst also changing the camber links on the front of the car to 0mm under the inner balls, and 0.5mm under the outer (ontop of the steering hub). Overall this gave the car a much better balance, with more middle corner steering. I actually set my PB lap with the second run using this setup, so pretty sure it was a step in the right direction.
One thing I started to notice after a few runs was a funny wear pattern on the front tyre, almost looking like the a ring forming on the outisde, rather than the inside. However, by then the day was up, and given I was pretty happy with progress, packed everything up and headed for the motel, and a few beers.

Unfortuantly, Saturday (and the first day of qualifying) started out wet... so much for getting to the track at 6am, barely saw any track action until 3pm in the afternoon! Did give me the opportunity to fully strip and rebuild the car (nothing else to do), as well as rebuild the diffs and shocks... Anyway, I started out where I had ended up on friday. Wasn't a bad first banker, a decent, if unspectacular run. Car felt slidey, which at the time I put down to the shock positions (which I adjusted for the second qualifier) however with hindsight, I'd made a big mistake of leaving the additive on too long, and this left the tyres slimy and horrible... which I only figured out at the end of the day, after the car still felt the same, albeit a bit better, in the second leg. The whole saturday wasn't helped by running F1 as well... which also didn't go well, so I was looking forward to sunday, which despite three rounds of qualy and three finals (to make up for the time lost for due to the rain) would be a bit more of a relaxing day.

With a bit of overnight pondering, I was still a little concerned that the same outside ring was forming on the front tyres. This caused me to think that something was up with the front link position, leading to the funny wear pattern. Looking in more detail, and comparing a few other cars, the front link was dropping at a downward angle (inner higher than outer), in effect causing neutral is not positive camber gain... I wanted to try a different additive technique in the first sunday qualifier, but had a plan on what to try for the later runs if needed.

Third qualy early on sunday was again decent enough, but made a couple of stupid errors and cost a lot of time. However the change in additive prep did work, and dropping the two worst laps, my consistency was at 0.15s, which was the sign of a good run. However, I still felt there was more to be had from the setup... and with three decent runs that put me solidy into the A, now decided to make some more changes, and try to further improve.

With looking at a few other cars, I realised that the low roll centre setup was a bit different to others, so I raised the balls 0.5mm all round (0.5mm F, 1mm R). Next on the list was playing with the front link angle. Taking a punt, I went with 1mm under the inner ball (matching the same as the rear inner ball), and 1.5mm under the outside. This gave the link a positive angle, and actually some camber gain... and the results seemed to tell on track, on for another 18lap run, faster than previous whilst on older tyres, until the speedo thermalled, and lost 12s on the last lap. What would have been a 5th in round turned into a 9th, but the pace was good. The general balance felt good, but the old nemisis of mid-corner rotation was still there.

The final qualifier, in an attempt to help the rear rotate more, I moved to the 1groove rear camber plates. Doing a bit of pitlane measuring, I figured that with the zero plates, the rear link is pretty long, even with the 3groove camber plates. From previous experience, going longer really helps to tie the rear end down, as it allows that end to roll more, without breaking traction (it's a more progressive roll). And... it helped

What was interesting, was that there was a certain section on the track that I had been struggling with all weekend. It was a partial power left hander, accelerating out of a tight hairpin, and leading into a tightening double apex left, with a bump in the middle of the braking area, so a lot going on! Watching other cars through there, the fastest guys looked tied down, but could adjust their line as needed. I had felt all weekend that I was on a knife edge through this section. The car would push whilst on partial power, and then snap badly over the bump, all the time losing time. With the change in rear link, the car improved a lot through this section. On a bit of further thinking, I feel it's to do with the long link "dumping" the grip suddenly when heavily loaded, which was the case in the bumpy braking area. With the longer link pushing more, it results in needing to be more aggressive to get the car turn in this section, and hence then snapping when you exceed the limit. With the shorter link, the car naturally turns better, and there is no need to be as aggressive, so the grip limit isn't exceeded, hence it felt more stable, and faster! This also helped the rotation of the car in the tighter turns.

Given that the change of the rear plates helped a lot with what I was looking for, for the last qualifier, I moved to the 2 grooves. I felt the balance was better again, although by this time the tyres were on their fifth run and feeling a bit old.. and again the speedo thermalled on the last lap, costing 10s and another 18lap run. But overall was pretty happy with the result, without the speedo thermals, I would have been a place higher on the A final grid, but even then would only have been 7th. I felt I had the pace to keep up with a couple of guys in front, and having kept two fresh sets of tyres, was feeling positive.

For the finals, I wanted to try the Yokomo springs again, as a couple of guys had been running using these to good effect, and I didn't have anything to loose from 8th on the grid First final was ok, unfortunately got caught up in a first turn crash by being wrong place, wrong time, so that left me last on lap one. Managed to get back up to 6th, but a fair way behind 5th. The new tyres didn't actually seem that fast, and a number of other racers were saying similar things, whilst the times also seemed to show that.

Second leg, only change was to move the shocks out one hole front and rear (to 3F, 4R), but didn't even make it to the first corner before being involved in a crash, as the guy ahead of me on the grid gave it too much grunt off the grid, and went sideways leaving me no where to go! Last again at the end of the lap... Got back up to 6th again, and had good comparative pace to the front runners, being the closest I had been all weekend.

For the last final, I went back to the Schumacher Greens, and lowered the shocks back to the previous holes (2F, 3R). Overall, this felt better.. but given a wheel nut fell off halfway through the run, didn't get a clean run, and this was after making it through the first turn this time! On a positive note though, didn't lose a wheel though! :P

During that last run, I got Simon Nicholson (multiple Australian Champ) to have a look at my car going around, and he pretty much described how it felt... a little understeery, but also rotates a bit too hard. Still quick, and would believe it would be right up there in better hands. I have a couple of ideas on how to improve the balance a little more, which includes the aforementioned ackerman plates, along with playing around with the front link a little more.

Still, overall a good weekend, learnt a lot, felt happy with the pace for most of the weekend, and didn't break a thing, bar stripping one spur. Not bad for three days worth of racing on a tough track!


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