All Exhaust Systems by Engine Model - Small Block Chevy 305 / 350 / 377, 5.0L / 5.7L, 6.2L Exhaust Systems

Powerflow Small Block System with Stainless Silent Choice Risers
Your Price:
$1,879.99

This Part has options, please click the button below to order.

Powerflow Polished Small Block Manifolds Only Kit

421-02-8051

Powerflow Polished Small Block Manifolds Only Kit 

Powerflow manifolds are manufactured using the finest materials and most advanced techniques available. The high quality aluminum manifold castings feature water jackets that surround each exhaust passage, including the port, to eliminate the possibility of burn out.

The outside manifold surfaces are polished. Features an external fitting to accept stock MerCruiser thermostat plumbing. Kit includes gaskets and bolts.


Powerflow Small Block System with Stainless Silent Choice Risers
Your Price:
$2,695.99

This Part has options, please click the button below to order.

Powerflow Polished Small Block System with Stainless Silent Choice Risers

421-02-8358

Powerflow Polished Small Block System with Stainless Silent Choice Risers

This popular system allows the use of a switchable exhaust diverter. These risers are stainless steel and custom designed to ease installation. They use a standard 4" diverter connection.

Powerflow manifolds are manufactured using the finest materials and most advanced techniques available. The high quality aluminum manifold castings feature water jackets that surround each exhaust passage, including the port, to eliminate the possibility of burn out.

The outside manifold surfaces are polished. Features an external fitting to accept stock MerCruiser thermostat plumbing.


Seaward Series "Alpha/Bravo HP Magnum" Small Block Chevrolet Exhaust System

Starting From:
$3,499.99

This Part has options, please click the button below to order.

Seaward Series "Alpha/Bravo HP Magnum" Small Block Chevrolet Exhaust System

620-38049 + Option(s)

  • Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • Perfect for use on OEM engines up to 450HP 
  • Magnum HP 500 Style Riser for performance applications
  • Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Kit includes all bolts and gaskets needed for installation

Seaward Series "Alpha/Bravo" Small Block Chevrolet Exhaust System

Starting From:
$1,999.99

This Part has options, please click the button below to order.

Seaward Series "Alpha/Bravo" Small Block Chevrolet Exhaust System

620-38045 + Option(s)

  • Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • Perfect for use on OEM engines up to 350HP 
  • Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Silent choice, captains call, and select sound exhaust diverter system compatible
  • Risers include O2 Sensor bungs and plugs.
  • Kit includes all bolts and gaskets needed for installation

Seaward Series "Dry Pipe" Small Block Chevrolet Exhaust System

Starting From:
$2,999.99

This Part has options, please click the button below to order.

Seaward Series "Dry Pipe" Small Block Chevrolet Exhaust System

620-38114 + Option(s)

  • Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • Perfect for use on OEM engines 500+ HP 
  • 4" Dry Riser for performance applications
  • Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Kit includes all bolts and gaskets needed for installation

Seaward Series "Low Exit" Small Block Chevrolet Exhaust System

Starting From:
$2,299.99

This Part has options, please click the button below to order.

Seaward Series "Low Exit" Small Block Chevrolet Exhaust System

620-38182 + Option(s)

  • Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • Perfect for use on jet boat applications or boats with a crank centerline style exhaust exit to 400HP 
  • Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Kit includes all bolts and gaskets needed for installation

Seaward Series "Ski Boat" Small Block Chevrolet Exhaust System

Starting From:
$3,599.99

This Part has options, please click the button below to order.

Seaward Series "Ski Boat" Small Block Chevrolet Exhaust System

620-38116 + Option(s)

  • Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • Perfect for use on OEM engines up to 400HP 
  • 3.5" Outlet Riser for performance ski boat applications
  • Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD  (3.5" outlet)
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Kit includes all bolts and gaskets needed for installation

Seaward Series 6.2L, 350 Mag MPI, 350 MPI Alpha-Bravo EC  (Catalyzed-Delete) 2" Taller Exhaust System

Starting From:
$4,999.99

This Part has options, please click the button below to order.

Seaward Series 6.2L, 350 Mag MPI, 350 MPI Alpha-Bravo EC (Catalyzed-Delete) 2" Taller Exhaust System

620-38208 + Option(s)

  • Eliminate Catalyzed Exhaust Systems
  • Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • Perfect for use on OEM engines up to 400HP 
  • Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Kit includes all bolts and gaskets needed for installation
  • Requires Catalyst Eliminator Computer (See Related Parts)
  • 2" Taller Than Stock Risers
  • We need to know your current riser height to make sure the risers will fit. See this image, we need height labeled "C". or find the part number on the riser such as in this image.

NOTE: THIS SYSTEM REQUIRES A HIGH DEGREE OF TECHNICAL APTITUDE TO INSTALL AND CONFIGURE. YOU MUST CALL AND SPEAK WITH OUR TECH SUPPORT DEPARTMENT BEFORE GETTING A QUOTE.

WARNING! This system is not to be used on emissions regulated waterways. The intent of this system is to allow the running of a catalyzed marine engine without the catalytic converters installed and without triggering any ECU error codes. With the engine operating in this condition, the emissions control system will be rendered inoperative. For this reason, do not operate the vessel on emissions regulated waterways. This system is not legal for any purpose other than testing purposes and not for use on any state or federal waterway.


Seaward Series 6.2L, 350 Mag MPI, 350 MPI Alpha-Bravo EC  (Catalyzed-Delete) Exhaust System

Starting From:
$3,899.99

This Part has options, please click the button below to order.

Seaward Series 6.2L, 350 Mag MPI, 350 MPI Alpha-Bravo EC (Catalyzed-Delete) Exhaust System

620-38123 + Option(s)

  • Eliminate Catalyzed Exhaust Systems
  • Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • Perfect for use on OEM engines up to 400HP 
  • Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Kit includes all bolts and gaskets needed for installation
  • Requires Catalyst Eliminator Computer (See Related Parts)
  • We need to know your current riser height to make sure the risers will fit. See this image, we need height labeled "C". or find the part number on the riser such as in this image.

NOTE: THIS SYSTEM REQUIRES A HIGH DEGREE OF TECHNICAL APTITUDE TO INSTALL AND CONFIGURE. YOU MUST CALL AND SPEAK WITH OUR TECH SUPPORT DEPARTMENT BEFORE GETTING A QUOTE.

WARNING! This system is not to be used on emissions regulated waterways. The intent of this system is to allow the running of a catalyzed marine engine without the catalytic converters installed and without triggering any ECU error codes. With the engine operating in this condition, the emissions control system will be rendered inoperative. For this reason, do not operate the vessel on emissions regulated waterways. This system is not legal for any purpose other than testing purposes and not for use on any state or federal waterway.


Seaward Series Replacement Small Block Chevy Manifolds
Starting From:
$1,599.99

This Part has options, please click the button below to order.

Seaward Series Replacement Small Block Chevy Manifolds

620-38 + Option(s)

  • Standard Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Silent choice, captains call, and select sound exhaust diverter system compatible
  • Sold in pairs
  • No tailpipes included, replacement manifolds only!

Seaward Series SBC Dry Joint Exhaust System

Starting From:
$2,799.99

This Part has options, please click the button below to order.

Seaward Series SBC Dry Joint Exhaust System

620-3813 + Option(s)

  • DO YOU HAVE DRY JOINT EXHAUST? CLICK HERE TO LEARN MORE.
  • Mercruiser Dry Joint Replacement
  • Replaces 14 degree, Dry Joint "Tall" Riser systems, "Short" 7 degree systems will require custom tailpipes
  • The term Mercruiser Dry Joint Exhaust refers to a later model (2002 and newer) OEM exhaust system which utilizes 2 coolant passages vs 4, between the manifold and riser that are separated outside of the exhaust gasket. 
  • Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • Perfect for use on OEM engines up to 400HP 
  • Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Kit includes all bolts and gaskets needed for installation
  • Risers include O2 Sensor bungs and plugs.
  • MerCruiser changed their exhaust system design in 2002 by creating a Dry-Joint exhaust system thus removing the cooling water passages from the perimeter of the riser and manifold flange area.  Dry-Joint is a proven enhanced design exhaust manifold and exhaust riser compared to standard “Wet-Gasket” style of marine exhaust manifolds and exhaust risers common to early or old style marine industry offerings

Seaward Series "Alpha/Bravo - 3" Taller" Small Block Chevrolet Exhaust System

Starting From:
$2,499.99

This Part has options, please click the button below to order.

Seaward Series "Alpha/Bravo - 3" Taller" Small Block Chevrolet Exhaust System

620-38044 + Option(s)

  • Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • Perfect for use on OEM engines up to 350HP 
  • 3" Taller Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Silent choice, captains call, and select sound exhaust diverter system compatible
  • Kit includes all bolts and gaskets needed for installation

Seaward Series "Alpha/Bravo - 6" Taller" Small Block Chevrolet Exhaust System

Starting From:
$3,499.99

This Part has options, please click the button below to order.

Seaward Series "Alpha/Bravo - 6" Taller" Small Block Chevrolet Exhaust System

620-38109 + Option(s)

  • Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • Perfect for use on OEM engines up to 350HP 
  • 6" Taller Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Silent choice, captains call, and select sound exhaust diverter system compatible
  • Kit includes all bolts and gaskets needed for installation

Seaward Series "Alpha/Bravo XL" Small Block Chevrolet Exhaust System

Starting From:
$2,799.99

This Part has options, please click the button below to order.

Seaward Series "Alpha/Bravo XL" Small Block Chevrolet Exhaust System

620-38048 + Option(s)

  • Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • Perfect for use on OEM engines up to 400HP 
  • XL Riser for performance applications
  • Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Kit includes all bolts and gaskets needed for installation

Seaward Series Low Port Small Block Chevrolet Exhaust System

Starting From:
$3,399.99

This Part has options, please click the button below to order.

Seaward Series Low Port Small Block Chevrolet Exhaust System

620-38106 + Option(s)

  • Manifold is powder-coated for corrosion protection
  • Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
  • Perfect for use on OEM engines up to 350HP 
  • Low Port Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
  • 356T Aluminum Heat treated tubular style cast internal manifold core for header like performance
  • Kit includes all bolts and gaskets needed for installation

Powerflow Small Block Kit with Stainless Risers
Your Price:
$2,789.99

Powerflow Small Block Kit with Stainless Risers

421-PFS-82AK

Powerflow Small Block Kit with Stainless Risers

Powerflow now offers a small block system. This system is designed after the big block kit using the same riser system. This system will increase your torque and horsepower by 10%. This system is also available fully polished, too.

Powerflow manifolds are manufactured using the finest materials and most advanced techniques available. The high quality aluminum manifold castings feature water jackets that surround each exhaust passage, including the port, to eliminate the possibility of burn out.

 The outside manifold surfaces are then coated with the highest quality epoxy powder coating available, creating a part that not only is highly corrosion resistant, but good looking as well. Features an external fitting to accept stock MerCruiser thermostat plumbing.


Powerflow Small Block System with Stainless Silent Choice Risers
Your Price:
$2,739.99

This Part has options, please click the button below to order.

Powerflow Small Block System with Stainless Silent Choice Risers

421-PFS-85SAK

Powerflow Small Block System with Stainless Silent Choice Risers

This popular system allows the use of a switchable exhaust diverter. These risers are stainless steel and custom designed to ease installation. They use a standard 4" diverter connection.

Powerflow manifolds are manufactured using the finest materials and most advanced techniques available. The high quality aluminum manifold castings feature water jackets that surround each exhaust passage, including the port, to eliminate the possibility of burn out.

 The outside manifold surfaces are then coated with the highest quality epoxy powder coating available, creating a part that not only is highly corrosion resistant, but good looking as well. Features an external fitting to accept stock MerCruiser thermostat plumbing.


Powerflow S-Pipe System - Small Block System Chevy with Stainless Risers
Your Price:
$3,799.99

Powerflow S-Pipe System - Small Block System Chevy with Stainless Risers

421-PFS-84SK

Powerflow S-Pipe System - Small Block System Chevy with Stainless Risers

This "S" pipe is unique in many ways. It has an infinite number of advantages. This pipe will size up to many pre-existing port locations. It's great for below platform applications with large camshafts or high performance motors. It allows the exhaust to mix with water down at the first connection.

Powerflow manifolds are manufactured using the finest materials and most advanced techniques available. The high quality aluminum manifold castings feature water jackets that surround each exhaust passage, including the port, to eliminate the possibility of burn out.

 The outside manifold surfaces are then coated with the highest quality epoxy powder coating available, creating a part that not only is highly corrosion resistant, but good looking as well. Features an external fitting to accept stock MerCruiser thermostat plumbing.


Hi-Torque Replacement S/B Manifolds Only
Your Price:
$1,779.99

Hi-Torque Replacement S/B Manifolds Only

520-35000

Hi-Torque Replacement S/B Manifolds Only (pair)

If you find yourself in need of maintenance accessories - we've got them! Gaskets, Clamps, Manifolds, Sealers. We've got it all!


Small Block GM Hi-Torque Standard Exhaust System
Your Price:
$2,969.99

Small Block GM Hi-Torque Standard Exhaust System

520-SM350K

Small Block GM Hi-Torque Standard Exhaust System (Exhaust Tips NOT Included)

The Hi-Torque manifolds feature state of the art design with single wall internal castings that are enclosed with an aluminum press formed jacket creating a fully water cooled manifold. A highly polished stainless riser comes standard as well as bolts, gaskets and fittings. This system also comes with an exclusive 60 month limited warranty.

All kits include: Shift, Module, and an Oil Filter Bracket