Hardin Marine

With the overwhelming success of the performance of Seaward exhaust manifold system it was only natural to expand into even more offerings. This latest version uses the popular Seaward Ocean Series manifolds combined with a intersecting companion pipe allow for direct replacement of rotting, cracked, failing original elbow top styled headers while providing the unmatched durability of a performance manifold system. This system allow's the original tailpipes to be reused for simplicity and affordability of exhaust replacement.

• Manifold is powder-coated for corrosion protection
• Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
• HP Riser for high performance performance applications.
• CMI Flange on riser uses existing tailpipes.
• Also replaces Mercury HP 500 EFI 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

• Manifold is powder-coated for corrosion protection
• Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
• Perfect for use on HP500, 540 Bulldog and other HP Bravo Applications.
• HP Riser for high performance 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 3" Taller Risers - Sold As A Pair

Seaward 6" Taller Risers - Polished - Sold In Pairs

Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD

These tailpipes feature a 4" O.D and a 3-1/2" I.D. for maximum exhaust flow.

Seaward 600/700 Risers - Polished

Seaward XL BBC Bravo Tailpipes - Sold As A Pair

Seaward Exhaust Manifolds Spacer Kits for 8.2L Engines with D Shaped Cylinders Non-Coated Stainless Steel

These spacers are for Hardin Marine Seaward Exhaust Manifolds specifically. These spacers allow for a proper gasket seal when mounting your new Seaward manifolds. Spacers are 3/8" thick. Made from stainless steel. Sold in pairs. Includes two gaskets for the cylinder head side and longer bolts for headers with 3/8" flanges. The bolts are specifically the correct length for Seaward manifolds ONLY.

For manifolds on these applications:

• 8.2L Mag EC (H.O. Model) 2A041665 THRU 2A051740)
• 8.2L Mag EC (H.O. Model) (2A051742 & Up)
• 8.2L INBOARO (H.O.) EC - [2A041665 & UP.)
• 8.2L Mag EC (Base Model) - [ 2A051743 & UP)
• 8.2L MPI Bravo - [1G400000 THRU 1G499999]
• 8.2L Mag (H.O. Model ) - [ 1A351597 & UP]
• 8.2L MP) Bravo - [1G400000 THRU 1G499999]
• 8.2L INBOARD (Base) EC - [2A041665 & UP]
• 8.2L Mag /Base Model) - [1A351597 & UP]
• 8.2L Mag EC (Base Model) - 2A041665 THRU 2A051741)

Seaward HP500 Standard BBC - Polished - Sold as a pair

Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD

These tailpipes feature a 4" O.D and a 3-1/2" I.D. for maximum exhaust flow. These systems are perfect for engines rated up to 525HP.

• Manifold is powder-coated for corrosion protection
• "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection is standard for 496 system.
• Designed for use as replacement for OEM Mercruiser 496 manifolds and risers 
• 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 brackets, bolts and gaskets needed for installation
• 2", 6", and 8" taller versions have 2-3 week lead time for custom tailpipe construction.
• Check your riser height to make sure you get the correct system.

Whether you're a tuner seeking to add a popular Air/Fuel ratio gauge or you're entering the world of aftermarket fuel injection we have developed the critical part to make this addition a snap. This billet aluminum anodized wedge is at just the perfect angle to allow re-connection of your original exhaust hose. The kit includes (1) O2 adapter wedge, (2) gaskets, and (2) new front attachment studs. Bolt pattern is 3" x 4.5". Designed to fit the Hardin Marine Seaward Manifolds only.

Seaward O2 Wedge / Gauge Kit

• Gauge kit includes custom tuned .1 AFR Resolution Bosch LSU 4.9 Sensor, 8ft. wiring harness, 304 stainless steel weld-in bung, mounting hardware, and detailed instructions for installation
• 0-5v data and serial data outputs for ECU, data acquisition unit, or Laptop tuning
• User programmable range for Rich/Stoic/Lean conditions
• Peak recall/memory
• 10:1 to 20:1 AFR range for gasoline applications
• 12 and 16 volt compatible, compatible with nearly every street car or race car electrical system
• User Programmable Warning Function
• Display data in Lambda or numerical A/F ratio

Whether you're a tuner seeking to add a popular Air/Fuel ratio gauge or you're entering the world of aftermarket fuel injection we have developed the critical part to make this addition a snap. This billet aluminum anodized wedge is at just the perfect angle to allow re-connection of your original exhaust hose. The kit includes (1) O2 adapter wedge, (1) gasket, and (2) new front attachment studs.

• 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

• 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

• 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

• Manifolds are powder-coated for corrosion protection
• Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
• Perfect for use on OEM engines 4.8 to 6.2L up to 500HP (Camshaft duration not to exceed 234 degrees @.050 Duration) 
• Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
• 356T Cast Aluminum Heat treated tubular tuned runner header style internal manifold core for header like performance 
• Drawformed Non-porous manifold shells are powder-coated for corrosion protection
• Silent choice, captains call, and select sound exhaust diverter system compatible
• High Performance Risers include O2 Sensor bungs and plugs.
• Kit includes all bolts and gaskets needed for installation

• Manifolds are powder-coated for corrosion protection
• "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
• Perfect for use on OEM engines 4.8 to 6.2L up to 500HP (Camshaft duration not to exceed 234 degrees @.050 Duration) 
• Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
• 356T Cast Aluminum Heat treated tubular tuned runner header style internal manifold core for header like performance 
• Drawformed Non-porous manifold shells are powder-coated for corrosion protection
• Silent choice, captains call, and select sound exhaust diverter system compatible
• High Performance Risers include O2 Sensor bungs and plugs.
• Kit includes all bolts and gaskets needed for installation

• 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 4.8 to 6.2L up to 400HP (Camshaft duration not to exceed 218 degrees @.050 Duration) 
• Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
• 356T Cast Aluminum Heat treated tubular tuned runner header style internal manifold core for header like performance 
• Drawformed Non-porous manifold shells are powder-coated for corrosion protection
• Silent choice, captains call, and select sound exhaust diverter system compatible
• Low Exit Risers include O2 Sensor bungs and plugs.
• Kit includes all bolts and gaskets needed for installation

• 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 4.8 to 6.2L up to 400HP (Camshaft duration not to exceed 218 degrees @.050 Duration) 
• Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
• 356T Cast Aluminum Heat treated tubular tuned runner header style internal manifold core for header like performance 
• Drawformed Non-porous manifold shells are powder-coated for corrosion protection
• Silent choice, captains call, and select sound exhaust diverter system compatible
• Low Exit Risers include O2 Sensor bungs and plugs.
• Kit includes all bolts and gaskets needed for installation

• Manifolds are powder-coated for corrosion protection
• Optional "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
• Perfect for use on OEM engines 4.8 to 6.2L up to 435HP (Camshaft duration not to exceed 228 degrees @.050 Duration) 
• Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
• 356T Cast Aluminum Heat treated tubular tuned runner header style internal manifold core for header like performance 
• Drawformed Non-porous manifold shells are powder-coated for corrosion protection
• Silent choice, captains call, and select sound exhaust diverter system compatible
• XL Risers include O2 Sensor bungs and plugs.
• Kit includes all bolts and gaskets needed for installation

• Manifolds are powder-coated for corrosion protection
• "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
• Perfect for use on OEM engines 4.8 to 6.2L up to 435HP (Camshaft duration not to exceed 228 degrees @.050 Duration) 
• Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
• 356T Cast Aluminum Heat treated tubular tuned runner header style internal manifold core for header like performance 
• Drawformed Non-porous manifold shells are powder-coated for corrosion protection
• Silent choice, captains call, and select sound exhaust diverter system compatible
• XL Risers include O2 Sensor bungs and plugs.
• Kit includes all bolts and gaskets needed for installation

• 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

• 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 4.8 to 6.2L up to 400HP (Camshaft duration not to exceed 218 degrees @.050 Duration) 
• Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
• 356T Cast Aluminum Heat treated tubular tuned runner header style internal manifold core for header like performance 
• Drawformed Non-porous manifold shells are powder-coated for corrosion protection
• 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

• Manifold is powder-coated for corrosion protection
• "Ocean Series" Extreme Corrosion Treatment available for additional interior corrosion protection 
• Perfect for use on OEM engines 4.8 to 6.2L up to 400HP (Camshaft duration not to exceed 218 degrees @.050 Duration) 
• Polished Stainless steel tailpipe is manufactured from premium 316L Stainless steel, 4" OD 
• 356T Cast Aluminum Heat treated tubular tuned runner header style internal manifold core for header like performance 
• Drawformed Non-porous manifold shells are powder-coated for corrosion protection
• 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

• 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

• 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 415HP 
• 3" taller riser for tall riser 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
• Silent choice, captains call, and select sound exhaust diverter system compatible
• Kit includes all bolts and gaskets needed for installation

• 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 415HP 
• 6" taller riser for tall riser 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
• Silent choice, captains call, and select sound exhaust diverter system compatible
• Kit includes all bolts and gaskets needed for installation