Matt’s Associated RC10B4 – February/March 2010 Update

After a frustrating event at the Petit RC where I ended up qualifying in the worst place possible (BQ or 11th) it was off to Worksop and the BRCA British Winter Open Championship. Going from high to low grip conditions meant making some changes before I went so that I would be in the ballpark. The first change was to move all the shock positions back in on the wishbone mounts and remove the rear anti-roll bar. The latter had been a very effective set-up change, despite this being the thinnest one that Associated offer. The tyres would remain the same, as would the inserts.

Alongside the suspension changes, I would also be running Speed Passion equipment in 2WD – a Pro GT2.0 speed controller and Competition 3.0 motor in 7.5R form. Installing this in the B4 was easy, and the connectors for the motor allow for quick motor changes. I opted for a 7.5R as along with the power from LiPo batteries, the wind has worked well indoors and out.

At Worksop, the car felt reasonable although the end of the straight, the sweeper tightened up and this unsettled the car as it was in a braking section too. No matter what I tried, it was inconsistent that was probably due to the fact that the suspension was loaded up, the car was changing direction and the steering angle was increasing. The brakes were quite severe, so I had a play with the speed controller’s initial and overall braking amounts. This would have been very quick had I not made such a tight installation of the wires. In order to plug in the programmer included with the Pro GT2.0 unit, you either need access at the receiver or speed controller end although both were not easy – a clear error on my part and one that I will have to rectify for the future.

Into the first race and I decided to move the shocks out on the rear to increase stability, and this also helped the car through the fast chicane in front of the rostrum. Despite a first lap lead, a small error saw me take second in the first race and a good start. During the rest of my races, I was still struggling with the end of the straight and this made me vulnerable as I found myself tuning the brake set-up just for this section and so leaving me with too little overall braking for some of the other areas of the track where more was needed. For the final couple of races, I decided to remove the lead plate that I run under the battery pack. At 125g, it’s a hefty piece and has a big effect on the handling. I also decided to adopt a different approach to the end of the straight by changing my line and using the front tyres to scrub speed instead. The combination of these appeared to work better and by the final race, I felt that I was at my most competitive, driving the neatest I had all day and turning the best laps.

One thing I noticed though was that the Speed Passion 7.5R motor might be switched to a 6.5R version for the outdoor season as it lacked a little top speed. In order not to over-motor the chassis, a smaller 12mm rotor will be used and this will offer less torque than the standard rotor.

Matt’s Associated RC10B4 Specification

• Car: Associated RC10B4
• 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 7.5R
• Batteries: LRP 5300 28C LiPo
• Charger: Much More ACDC Silent Charger Platinum LCD
• Gearing: 25/78

Set-Up

• Front Suspension
• Oil: 35wt
• Piston: Ghea #2
• Spring: Associated Silver
• Anti-Roll Bar: None
• Shock Position Mount: Middle
• Shock Position Wishbone: Inside
• Caster Block: 30-degrees
• Rear Suspension
• Oil: 30wt
• Piston: Ghea #2
• Spring: Associated Silver
• Anti-Roll Bar: Thin
• Wheelbase: Short
• Anti-Squat: 2-degrees
• Shock Position Mount: Middle
• Shock Position Wishbone: Outside

Notes

• Schumacher Yellow Minipins
• Front soft insert
• Rear soft insert
• Front tyres with a row off inside and outside
• RudeBits 72g brass weight under servo
• RudeBits brass weight (one per side) in rear of chassis

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