Now Available From Scott Drake are the 1964-68 Mustang 2.25" 'H' pipe with High Performance Exhaust Manifolds. This oversized 2.25" 'H' pipe is designed to bolt up to Factory 289 High Performance cast iron headers used on 'K' cars. Designed to mate up to one of our two performance dual exhaust systems (C5ZZ-5257-FLM or C5ZZ-5257-TTQ).