The best I can find is the 2007 regs on the BRDA website. They should be OK as I don't think anything has changed except for the control tyre.
for regs
Click Here (pdf doc)
If yopu are looking at the BRDA/MSA championship the control tyre is the Kumho V70A. If you are looking at the MDA championship then its the Silverstone type RR.
If on the other hand you are looking at the BTRDA, then you have a little more choice of tyre you can use.
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