Please Note!!
All cars in all classes must run the approved muffler for that class AND be no louder than 95 decibels at 100 feet. Please refer to individual class rules for muffler requirements. Mufflers listed on IMCA rules as optional are MANDATORY at Cottage Grove Speedway. Mufflers must be unaltered and intact at all times!
Rules subject to change, updates, and clarifications at tech officials discretion.