Hello Paul,
That is an interesting post - racing the CSRs must have been fun. Your comment about snap oversteer is interesting too - I have not been able to find information on the HPC tyre sizes, but it seems unlikely that the rear ones were as wide as on the CSR 260. The main difference wider tyres bring is smaller slip angles for the same side force, so wide rear tyres increase static direction stability and this may need a rear ARB to reduce it and make the car more agile.
It seems that I can quote Peter Ballard without compromising TM rules. He says that Nitron have a reputation for setting their dampers stiffer than SSL, so it seems worthwhile to try reducing damping by a couple of notches and seeing what effect it may have. An easy way of checking it is to find some speed bumps and take them at a slow speed, but fast enough to drop the car off them - this will act as a forcing function and you can observe the number of overshoots. You can also drive over speed bumps with just one set of wheels, pause on the top, and observe the roll angle. The height of the speed bumps and photo through the windscreen of the roll angles would be useful. If you have a rear ARB they will probably not be much difference between the front and rear, but if you do not you can expect a lot more roll angle from the front.
I bought my car Williams, and they turned out to be an excellent dealer. They race two teams - Caterham and Morgans, including a CX, and have a Flat Floor capability. I will try and persuade them to get wheel rates and roll stiffness specification, which would provide some light on the rear ARB. They fitted one to the racing CX, but have not yet tried it out. They had to drop the rear subframe, modify it, fabricate down links but I am not sure if they had to modify the rear suspension to make connections for them. They offered to fit one to my car when they were fitting the Nitrons, but I was a little cautious about it. More data would help… and I am curious to find what your comments are.
All the best,
David Poole
