F3.0 update from BRCA 10th Electric Circuit 2WD Nationals round 4.

This round was at my home track so this gave me a great opportunity to experiment deep into a different set up. The changes gave me an extra 3 seconds improvement over my previous PB and the car was lovely to drive like this. I qualified P6 and finished P7 (crazy wet finals). P5 could have been achievable with everything perfect. The competition here was crazy fast and really close.

Main changes from my usual type of set up were to completely lock down the flex everywhere possible with an uncut top deck, then use a softer spring and damping package all round. The Bedworth track is super smooth and high grip and you always end up searching for more front end, so soft springs and light damping really helped here. Damping was achieved by redrilling a set of 4 hole pistons to 1.3mm and going up ~100cst in oil. This gives a softer damping effect with less pack and lovely quick but controllable response. To recreate this easily, I estimate this gives a feel of ~300-325cst if using the stock size 4 hole pistons.

Other changes involved flipping the bulkhead caps front and rear for more static castor. The top arms are also angled which gives dynamic castor change under compression. At the front end, the top arm being higher at the rear has the effect of reducing castor slightly at the apex, this helps tuck the nose in at slow speed. At the rear, the top arm being higher at the rear adds to the effect of the increased static castor to amplify the effect of the extra rotation this brings. I also added a stiffer rear ARB to again increase rear rotation and added higher roll centre shimming at the rear under the upper and lower arms to work the rear tyre less and again help increase rotation. You'll also see a very high rideheight rake angle. This keeps more weight over the nose and helps the rear rotate more. With the main elements of the set up decided at the start of the day, I tuned the balance with only rear rideheight and toe changes. Each round I would reduce rear toe a little and add 0.2 rear rideheight until hitting 0 toe and 6.5 rear rideheight. This is as far as you can go before becoming unstable and snappy. This keeps rotation up throughout the day as the grip increases.

I would recommend using some of these set up tricks on a very high grip super flat track. I'll be giving this a go when it comes time to head back indoors. Please drop a comment below or PM me if you have any questions and I'll be happy to help.

Thanks to Zen-Racing for the support and David Spashett for the technical discussion leading up to this round. I don't think a top 10 would have been possible here without the extra input.