CMI 496 E-Top Polished Exhaust Header Systems 

How to measure riser height

Direct Mercruiser replacement for your 496 Mag or 496 HO engine. 8-1/2" Stock Riser Height. Polished. No additional custom tails to buy. You don’t need to remove your stock exhaust hose to install this kit, a true plug and play system. No additional custom tails to buy. You don’t need to remove your stock exhaust hose to install this kit, a true plug and play system.

• 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
• Seamless water jacketed header. 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
• Cool collar patented flange design to eliminate the risk of getting water in the motor by the head flange
• 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.