single exhaust for 318...what size??

Our Race Car is the record holding NHRA E/SA 1974 Dart Sport and we actaully use a single exhaust outlet on it. Its a great idea to use a single pipe, creates more scavenging. Doing the math I personally would use dual 2 1/8" pipes coming off the manifolds into a 3" pipe to the back. This would easily support much more HP than youll ever make. Make sure you use a nice merge collector from the dual 2 1/8" pipes to the 3", this is important for scavenging.

Mark Lelchook
Performance Welding
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