The square set-up wheels and tyres are finally fitted (no pictures as yet, as it is absolutely caked in road grime and was dark when we finished). What a
mission that was, had to change all four bearings and getting the hub nuts off nearly broke the bar as we had to use a 7ft length of 2" box section to crack them. All to fit some longer wheel studs to accommodate the 15mm spacers
. What a poor design - Cossie ones can just be pushed out on the car
I was warned on S2ki that the AD08s would not be as good in the wet as the RE50s, but my experience is the opposite. They offer far more grip in these conditions t than the Bridgestones (although mine were almost down to the wear indicators). Obviously I am talking about the damp greasy conditions we are currently experiencing, not full on water moving scenarios, as then that is what you would expect, as the tread on the Yokos are new compared to my worn RE50s. However, the Yokos are also better in standing water as well, but as stated, that was to be expected.
Previously it would slide really nicely in second gear in these damp slimy conditions from relatively low rpm, but now with the AD08s fitted it requires much higher rpm to get the rear moving or some serious provocation.
The extra grip the tyres are giving means that you can actually feel the diff working as the tyres load up and are on the cusp of spinning (you can feel it shuffling the grip from side to side as it locks and unlocks balanced on the throttle). This actually means you can drive far harder in these conditions than I would have ever dreamed of doing with the RE50s. But the flip side of the extra grip is that the car isn't as much fun in this weather, as the breakaway point is that much higher and so I am reluctant to push it to slide as the speeds are higher (and I don't want to crash it LOL).
I now can't wait for the next track day (Bedford on the 25th Feb) to see how they fair with some proper heat in them. Regarding the square set up, it looks good, but you can feel the extra weight of the wheels and tyres up front, as the 8.5" wheels with 245/40 tyres are 3kg each heavier than the 215/45s on the 7" rims, so the extra width and weight means you loose the delicacy of the original set up. I have also gone more aggresive on the geo (thanks to Andrew for the recommendations), which means the car follows imperfections far more and makes the steering a bit more "busy".
Hopefully the extra front end grip on track will outweigh the down sides, but until I refit the 7"s (with AD08s as well), I don't know how much of this heavier steering feel is down to the extra weight and grip of the wheels and tyres or the aggressive geometry (up from almost 1° neg to just over 2° on the front). The rear was also set to 2° with 1.5mm overall toe-in and the front parallel. We corner weighted it as well, and it is a lot heavier than previously, as this time all the fluids were at the max (I had just brimmed both the fuel and the washer bottle (this part due to the weather)), where before it was measured on a half tank of fuel.
A good balance, but makes me realise just how heavy this car is (my CSL is only just over 100kg heavier and that has four seats...).
I think I will need to adjust the ride height a fraction, as the fronts "just" catch the outer archliners on big compressions. It is currently 635mm from ground to arch on the front and 655 on the rear - I think 5mm more on the front will "hopefully" cure that (sad, because it does look nice like this).