- Schumacher Cat SX - Matt Benfield - EPR & Oswestry - June & July 2010 -

Matt’s Schumacher CAT SX Specification
* Car: Schumacher CAT SX
* Radio: KO Propo Vantage III Universe
* Receiver: KO Propo KR-302F
* Servo: Spektrum H6040
* Speed Controller: Speed Passion Pro GT2.0
* Motor: Speed Passion Competition 3.0 5.5R
* Batteries: LRP 5300 45C LiPo
* Charger: Much More ACDC Silent Charger Platinum LCD
* Gearing: 21/83

Set-Up (PDF)

Front Suspension
Oil:40wt
Piston: Three-hole drilled to #55
Spring: Schumacher Grey (old)
Track Washers: 1mm front and back
Anti-Roll Bar: None
Shock Position Mount: Middle
Shock Position Wishbone: Middle
Front Rake: 10-degrees
Caster Block: 10-degrees
Washers: 0mm
Front Link Bracket: 38mm
Washers on Hub: 0 (hub carrier trimmed down level)
Rear Suspension
Oil:30wt
Piston: Three-hole drilled to #54
Spring: Schumacher Red (old)
Wheelbase: Short
Toe In: 3.25mm
Anti-Squat: 1.3-degrees
Rear Link Bracket:37.5mm
Washers: 3mm
Shock Position Mount: Middle
Shock Position Wishbone: Inside
Hub Position: Middle
Anti-Roll Bar: None
Transmission
Rear Diff Height:Low
Front Diff Height:Low
Layshaft Pulley:One-way
Front Drive:Diff
Gearing:23/83
Internal Ratio: 23/33
Notes
Schumacher Yellow Minipins
Front firm insert
Rear soft insert
Diaphragm centre cut out and removed
130g lead plate under chassis

Bringing you up to date with the progress of my racing sees me attend the two Nationals at Eden Park Raceway and Oswestry. My first two Nationals had seen me take eighth and 19th so I was looking for strong results at my home track and the all-grass venue in Shropshire.

With Eden Park Raceway being my home track and one that I am deeply involved in, there is all sorts of pressure on myself to do well and that a lot of expectation I put on myself. In 2009, I made the A final with the new CAT SX so after another season of racing, I was keen to repeat the success at EPR. In truth, the CAT SX set-up hasn’t changed that much although I still play around with camber link positions, rear shock oils and sometimes the weight. Normally, I can tune the handling by trimming the tyres as the base set-up for me works on most surfaces.

The day started well in 4WD as my first qualifier saw me fourth in the round, really getting into a groove towards the end of the run, pipping Danny McGee to the place by just four tenths of a second over the last couple of laps and four seconds off the round winner Simon Moss, also with a Schumacher car. My place was almost cemented in round two when I qualifier seventh in the round giving me 11 points in total but I don’t like to think that this is an assured A final score as I have attended nationals when ten points has been pole in the B final but personally, I have also made the A final in the past with 21 points. Anyway, I wanted to improve my score but threw this away in the third run by only being 15th fastest. Into the last run and things were going to be close. Fortunately, I had my best run of the day to take fifth in round some five seconds off the pole time but very happy with a drive, especially when I had put myself under some pressure to improve. The CAT SX had been great all day with the only changes being to fit new tyres after two runs and recharge the LiPo. Whereas in the 2WD I make two runs on a pack, I haven’t tried this in 4WD yet so it gets replaced with a freshly charged pack each time I go out on to the track. I was still using the CAT SX shocks, which are referred to as the small bore ones even though the big bores were available and fitted to the cars of Tom Cockerill and Simon Moss. Grant Williams and I worked hard on the suspension settings to get them right and we have always gone well with the older shock design. The only negative is that they are higher maintenance and seem to require oil changes more than others. Due to the grip and conditions, we decided to increase the rear oil to 32.5wt to support the rear end better as in previous meetings, we have felt that 35wt can be too stiff on a bumpy track.

Into the A finals and the first two went well with a sixth and an eighth but I broke in leg three meaning that I would be unable to improve on my score. It was an accident as Tom Yardy’s Yokomo had hopped sideways exiting the bomb-hole, gripped up and stopped. I was committed to the line and with nowhere to go, hit Tom’s rear wheel with my car and snapped the front shock shaft. It was not Tom’s fault although he did apologise, but this meant I would drop a couple of spots on qualifying and finish ninth.

It was off to Oswestry next and a place where last year I lost all confidence in the car. I now look back to that meeting and feel I know what went wrong as the car usually is impeccable. After round four of the Nationals in 2009, I followed the lead of Grant Williams by running some lead plate under the chassis. This has the effect of reducing the speed at which the car changes direction, as well as making it more planted on the track. No doubt that this makes the car ultimately slower but it tends to suit my driving style better, especially as I get older! Since then, very rarely have I taken this off as the tracks have been high grip but back in May 2009, the car was a handful and Team Manager Phil Booth was keen to increase the stability of my car. But my confidence had been shattered and I struggled, only making the C final with a car that the meeting before had qualified in the top six of the Talywain National. So this year I wasn’t going to make the same mistakes and I headed up the motorways with optimism.

With plenty of commitments to work and the family, I am afraid I don’t get to many of the regionals in my area that have grass tracks so its usually the Oswestry round of the series that I get my annual run out on the green stuff. I have to say that I have no dislike to the surface, but just sometimes, I don’t gel with it that well. Although 2010 was notably better then 2009, I never had the raw pace and was consistently in the low teens come qualifying. Ending up in 16th place after qualifying, I decided it was an opportunity to try the big bore shocks and they were hastily put together with help from Trish Neal and parts supplied by Trishbits, as well as Schumacher drivers Tom and Simon. By the time we headed out for the B final, the track had taken a real beating and was pretty much free of grass in the corners. We had guessed on shock pistons and oils and although the car felt OK, the rear diff had gotten a little notchy and was starting to tighten up meaning oversteer on the way out of the corners. I dropped to eighth in the final and didn’t set any amazing laps so I knew very quickly that I would revert to a known set-up for the fifth round of the series at Southport in July.

Thanks to Jimmy at oople.com for the photos.

Thanks to everyone who assists me with my racing including:

* CML Distribution
* Horizon Hobby UK
* JConcepts
* LRP
* Much More UK
* RudeBits
* Schumacher
* Speed Passion
* Trishbits
* Upgrade

Source:

RC Racer