Custom Marine Inc. - 8.1L 496 Chevy

CMI 496 E-Top Satin 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.

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 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.

ALL CMI HEADERS ARE MADE TO ORDER AND SHIP FROM THE FACTORY IN 3-4 WEEKS

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.

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 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.

ALL CMI HEADERS ARE MADE TO ORDER AND SHIP FROM THE FACTORY IN 3-4 WEEKS

CMI 496 E-Top Tall Polished Exhaust Header System, 2" Taller

How to measure riser height

Direct Mercruiser replacement for your 496 Mag or 496 HO engine. 10-1/2" Stock Tall Riser Height. Polished. 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.

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 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.

ALL CMI HEADERS ARE MADE TO ORDER AND SHIP FROM THE FACTORY IN 3-4 WEEKS

CMI 496 Sport Tube Exhaust System

The CMI 496 Sport Tube Performance Package delivers improved performance across the entire operating range of any 496 engine package. When applied to a stock 496 engine, this package will help to increase horsepower, boost mid-range torque, improve fuel economy across the power curve and enhance the engine's overall running quality. The package comes complete with all required mounting hardware plus CMI's exclusive 496 Relocation Kit, which includes all brackets, hoses and hardware needed to make relocation of select engine components easier.

Note: All CMI Systems are sold without Tailpipes

ALL CMI HEADERS ARE MADE TO ORDER AND SHIP FROM THE FACTORY IN 3-4 WEEKS

CMI 496 Sport Tube Internal Sound Choice Exhaust System

The CMI 496 Sport Tube Performance Package delivers improved performance across the entire operating range of any 496 engine package. When applied to a stock 496 engine, this package will help to increase horsepower, boost mid-range torque, improve fuel economy across the power curve and enhance the engine's overall running quality. The package comes complete with all required mounting hardware plus CMI's exclusive 496 Relocation Kit, which includes all brackets, hoses and hardware needed to make relocation of select engine components easier.

Includes Pneumatic Pump Kit for Internal Sound Choice

Note: All CMI Systems are sold without Tailpipes

ALL CMI HEADERS ARE MADE TO ORDER AND SHIP FROM THE FACTORY IN 3-4 WEEKS

CMI 496 Sport Tube Straight Pipe Exhaust System

The CMI 496 Sport Tube Performance Package delivers improved performance across the entire operating range of any 496 engine package. When applied to a stock 496 engine, this package will help to increase horsepower, boost mid-range torque, improve fuel economy across the power curve and enhance the engine's overall running quality. The package comes complete with all required mounting hardware plus CMI's exclusive 496 Relocation Kit, which includes all brackets, hoses and hardware needed to make relocation of select engine components easier.

Note: All CMI Systems are sold without Tailpipes
ALL CMI HEADERS ARE MADE TO ORDER AND SHIP FROM THE FACTORY IN 3-4 WEEKS