I remember those. The inside tube had punctures all along it's length. Looked like someone used a "church key" (pointed bottle opener, for the pop top generation) that directed some of the exhaust into the insulation chamber around the outside of that tube. The "in" crowd would put them on backwards for that real race car sound. umhuhyea they were loud back then. Might have other designs now.
The lighted cherry bomb decal was cool too!