Tony-I just went. It is still under repair with cones on the straight. a wet patch at the end of the straight. Traction low. I was able to squeeze through and drive around the wet patch most of the time.
Dual A-arm Front End Track Report
My new Murdoch RC springs did not come yet, but the sun came out for the first time in a couple of weeks. I managed to get some practice in. The car was better with all the changes I made. It still had too much turn in. One problem that Mathijs mentioned recently is the GTB puts on about 20% drag brake in its stock profile. Now that the car steers aggresively this became a problem. I reduced it to 5%. I do notice that you can reduce it to 0, I may try that next time.
The new front end was very responsive to roll center changes. I added another washer under the outer upper A-arm pivot. This helped. I added a washer under the suspension uprights and then adjusted the shock collars for the same ride height. This had the most effect and made the car almost perfect. I probably need that 15 # spring or maybe not.
Manners on the straight:excellent.
Very high grip on the sweeper now. I should be able to pick up time there.
The rear was kicking out just a little (loose) on turn 1 which is a fairly high speed right hander. It was a bit dusty there so this may go away.
Extremely good turn in on turns 7, 9 and 10 the hairpins near the drivers stand. Less drag brake will speed things up here.
If you need more steering this is the setup to have. Ecessive steering can be tuned out nicely, but there is alway more in reserve should the need arise to tune some back in.
Camber Curve and Tire Scub
I'll have to mention that if you roll the car on the bench, the front tire has a beautiful camber curve. The camber is almost unchanged with roll, a slight negative camber gain. If you push the chassis down (go into bump) there is almost no sideways scrub of the tire to take away speed. These are the benefits of the long and short A-arm. A race and a comparison to Marty's equal length arms will tell more if these are an advantage or not. I am sure that Mathijs will get his chance at these arms as well.
The pic shows the front suspension member angles that are working quite well. The roll center is probably 3-4 mm up from the ground. Front ride height is at 6.5 mm
No durability problems to report except the kingpin nuts came off twice. I think I will use my longest regular pins instead. The nuts are too close to the plastic. The pins are not long enough to space them away.