For high temperature coatings including automotive/motorcycle exhaust systems, metallic ceramic coatings are the answer.  These are liquid applied coatings that have aluminum and ceramic components in the resin formulation.  These specialty coatings are not to be used for food preparation surfaces.  Not to be confused with traditional silicone based high temperature powder coatings, these coatings are resistant to upwards of 2000°F. These coatings will lower under-hood temperatures and extend exhaust component lifespan.  A slight increase in horsepower and torque are the result of better flame scavenging through more retained heat within the exhaust stream.  Metallic ceramic coatings are a thin-film coating and thus are not designed for heavy impact or scratching from sharp objects.  They do however provide a proper coating for high temperature applications.  For BBQ, manufacturing equipment and other mid-range, high temperature coatings, ask your Andrews Powder Coating, Inc. representative for information about silicone based high temperature powder coatings.