A. The exhaust flow must be parallel to the ground. Exhaust systems that direct the flow toward the ground will not be permitted.
B. All exhaust systems/headers must end with a collector.
C. Several tracks have a locally enforced decibel rule, which preempt any particular muffler rule. Some tracks may have a maximum sound level rule of 95 decibels at 100 feet. This rule will be enforced by local government agencies.
D. If a decibel rule is in place, then the decibel rule must be met, regardless of the specified muffler application.