actually most of entrants would be in A-D
E-H are those with engine swaps, stripped down with aero work...think richo's skyline.
http://www.piarc.com.au/files/Feb%202015%20Sprint%20Regs.pdf
Classes A, B, C & D are for road-registered cars using generally road-going equipment only. All cars using racing
tyres, or slicks, will be classified as specials, as will be excessively modified road cars. The organisers reserve the
right to re-classify cars, following vehicle scrutiny. For full details of modifications allowed in each class see Group 5
Speed Event regulations. The organisers reserve the right to amalgamate classes if in their opinion entries are
insufficient to warrant a separate class.