Ask The Answer Person: "Who is responsible for seeing that all race cars at the Upper Iowa Speedway have "muffles/baffled pipes"?

Carol e-mails: "Dear Mr. Answer Person, The City of Decorah now has a Memorandum of Understanding (MOU) with the Upper Iowa Speedway.  The MOU states that all cars must have 'muffles/baffled pipes.'  Who is responsible for seeing that all cars in are compliance?  Also, the MOU says races shall end at 10:00 p.m. but on RARE occasions, due to rain delays and 'circumstances related to USRA sanctioned scheduling (one race)' the races can continue past 10:00 p.m. but MUST end at 11:00 p.m.  What does, '… circumstances related to USRA sanctioned scheduling' mean?  And how often do these USRA sanctioned races occur?"

The Answer Person says: "Let's tackle the USRA question first.  The initials stand for 'United States Racing Association.'  You can find the rules USRA member racetracks adhere to at: http://usraracing.com/rules/.

As for the 'muffle/baffled pipes,' this refers to equipment which reduces the noise from race cars.  Upper Iowa Speedway is the only NE Iowa race track with this requirement.  This rule is agreed to by race car owners and drivers—so it is self-policing, with the race organizers making sure the rule is followed."