Originally Posted by M3Racer
From the measuring and research that you guys have done, do you think we will have any clearance issues at all with plus-sized (275/305) tires on these wheels?
I'm thinking of going with H&R lowering springs around the same time and I don't know if I should be looking to achieve more negative camber somehow at the same time or not...?
Also, does anyone know if the speedo is based on rotation or some other method? With plus size tires, we'll be off from the stock overall diameters by as much as nearly 4%. Is there someway to fix or compensate the speedo (and odometer) error that would come with the different tire heights?
Guys.. the complete answer to this question will have to wait until Shep returns from the track this weekend. For the most part I am the administrative arm for this project.
I can comment that RAC builds aggressive fitments that not only look appealing, but function as well. For instance the M3 fitments are as aggressive as can be spec'd yet still allow considerable height adjustment.
There are many parameters with that can have an influence on fitment. Tire size, tire brand, ride height, spring choice, and alignment parameters are some to name a few. That said.. normally our specs allow quite a large range of adjustment.
Below is my car on RG4s.. the offsets were nailed perfectly!
With aftermarket tires.. sometimes you make a sacrafice depending on how their diameters compare to stock. The speedometer can be off although not much. This is the price you pay for increased grip, traction, and aesthetics.
The beauty of the M5 RG41 specs as I understand them is you will be able to run the stock rubber on the wheels if you like. All while widening the track of the vehicle which can enhance the car's dynamics tremendously.