XRAY - Model racing cars

Hi.
I have low and medium grip on my track. Please advise me which body will better to use? And second question about set up.
On the team drivers set up blank, i often see words:" ride height measured on blank rims".
Is it men usual rims just without tires? Or something else?
Thanks.

Rims without tires! As the setup sheet states. Which means 50mm wheels.

Protoform SRS-N is a good body for the conditions that you describe.

Hi Alex. Thanks for your answer.
Do you mean what for in this case i need to use 50mm rear rims in rear and 50mm front rims in front or not important? i just think, what if rear wheels have camber about 2-3 deg, then the width of the rear rims affects the ride height. if i will use front rims or rear rims ... it may have about 0.5mm difference. Right or i am mistake?
and some questions about your set up (ENS RD3).
In comments you wrote: "Rear wheelbase shortened by 2mm". How can you make it? do you change width of rear arms? What effect you would get from this change?
also I'm interested in the using of brass battery holder. Does it make sense to use it if the weight of the model is not limited and you can make a model less weight? I understand that in general the use of brass lowers the center of gravity but that in this case is more important for the setting. lighter weight or lower center of gravity?

Do you use 25 0r 26 pulley?
Do you use smaller diameter wheels for qualification?
Do you use rubber grommets for mounting of servo?

Thank you for your answers, they are very important to me

guys, Can anyone answer my questions????

Thanks