CMI Header Applications

Available Systems

Sign up for the
CMI e-newsletter

Stay up-to-date on new products, promotions and events.


CMI Industrial is proud of its heritage as a designer and manufacturer of top-quality sound and noise attenuation systems that have set the benchmark for quality and innovation. CMI has enjoyed a decades-long leadership position by offering unparalleled products and services, and maintaining industry-leading customer satisfaction.

Visit CMI Industrial

CMI 496 E-top Headers

CMI 496 E-top Headers

“I recently installed CMI's new 496 Elbow Top header package on my boat. All I can say is WOW! I gained 4 mph . . . the throttle response has also greatly improved. The best part, I did all the work myself.”

Todd R. / Linwood, MN

  • Direct Mercruiser replacement for your 496 Mag or 496 HO engine.
  • No additional custom tails to buy. You don’t need to remove your stock exhaust hose to install our kit, a true plug and play system.
  • This new kit introduces CMI’s new low cost satin finish. For an additional charge you can have our classic high polished stainless finish.
  • 1 7/8" id primary to get peak horse power and torque.
  • Mandrel bent and formed from High quality 316L grade material.
  • Fully post annealed to reduce stresses built up in the header during the manufacturing process
  • The only seamless water jacketed header manufactured. No welded inner primaries or water jacketed tubes to crack and leak.
  • More water jacketed protection than your stock exhaust.
  • Approved by Mercruiser to not void warranty on the motor, with the exception of water reversion.
  • Same high quality semi automated welding as used on all racing applications
  • Patented “Cool Collar” design provides a short hot section at the flange, which helps minimize the possibility of water ingestion in to the engine.
  • This kit is price competitive to other aluminum/stainless manifold systems with superior performance and extended life span in harsh marine environments.
  • No cast parts to crack, all CMI collectors are forged from American made stainless steel.
  • Works on 34.5" drive centers
  • Brings a race look to your stock engine.
  • Sophisticated engineering leaves your stock oil lines in place and only requires relocating your oil filter with a supplied bracket.
  • Step by step, do it yourself instructions using Mercury supplied engine schematics.
  • Exhaust Water Temperature Bungs Installed as Standard Equipment.