[F500] Any road racers use mufflers?

[John Whitling]

    At the SCCA Solo 2 nationals we had two competitors disqualified 
because their exhaust was more than 24" past the rear axle (they were 
about 2 1/2" longer than the max). The reason they were long was because 
they had mufflers, which the protest commitee reasoned was part of the 
exhaust. Mufflers are not required, BTW. The cars involved have Rotax 
motors with Aaen pipes and mufflers. They do not have a custom exhaust.

If you ever have to use a muffler at a track to make the sound limits is 
the 24" rule superceeded, or are allowances made for the muffler?

Thanks
John Whitling