Seaward Series "Bravo" Big Block Chevrolet Exhaust System

  • 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 
  • 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
  • Risers include O2 Sensor bungs and plugs.
  • Sold in pairs

The Seaward exhaust systems will be the biggest market changing product to debut in 2016. These exhaust systems were not only created using the most modern robotic electronic machine operations but with state of the art tooling. What does all of this mean? It means you can now buy the very best reliable performance exhaust manifold system that money can buy for a whole lot less money.

Hardin looked at the exhaust market in the same fashion the worlds top manufactures have in that through the most modern state of the art design and production efficiency we could build the best product and reduce the overall cost by hundreds of dollars over anything even remotely comparable in the world today

The SEAWARD debut is a 100% all new design these exhaust systems were built to provide virtually every feature once desired in a performance marine exhaust system with reliability and longevity being the key features.

The Seaward Standard system is designed as the ultimate OEM replacement exhaust system in the world today. The Standard length riser makes this system perfect for use on OEM engines up to 415HP and will allow easy connection and use of either through hull hose connection or silent choice , captains call, and select sound exhaust diverter systems. The stainless steel tailpipe is manufactured from premium 316l Stainless steel not 304/303 low grade SS many competitors use. these tailpipes feature a 4" O.D and a 3-1/2" I.D. for maximum exhaust flow.

Here's the facts: There is no other performance exhaust manifold system on the market today that with as many features and advancements in construction PERIOD. Starting with a 356T Heat treated tubular style cast internal core that has been optimized to flow with the technology design and shape and design of a tubular header. By extending the runners and separating the exhaust pulses to the collector this system produces maximum power in a compact design.

More Facts: The optional "Ocean Series", 1000 hour salt spray coating provides extreme corrosion treatment. That's right this industry has never seen these types of processes. These products are extending the naval and aerospace program products as much as ten years. Sure the finish is that of a show piece, but it's truly what you can't see that sets these systems apart. Underneath the thick non-porous billet heat treated aluminum casing lies the most exceptional foundation of corrosion protection found anywhere. A hydrogen infused zinc process is applied to each manifold. Until now salt spray testing could merely only withstand 100-150 hours of sustained exposure, Today those numbers are 1000 hours of durability.

More facts: Beauty is well beyond skin deep here as the beautifully polished stainless steel exhaust risers of the systems are manufactured from 316L Stainless Steel while inferior systems choose inferior stainless (303/304 Auto Grade) steel, Seaward systems offer nothing but the best money can buy which has been proven to be the most durable long lasting product for marine use.

Fits: Standard Bravo and Silent Choice Applications up to 415 HP.

The big-block Chevrolet has a firing order of 1-8-4-3-6-5-7-2. This means that In each exhaust manifold, we will have two cylinders that will fire In succession. Cylinders 8 & 4 on the starboard side manifold and cylinders 5 & 7 on the port side manifold. In the images of the competitor exhausts below, we can see the manifold has a divider that separates the exhaust pulses from cylinders 8 & 4. This divider keeps the exhaust gases of the number 4 cylinder from entering the number 8 cylinder when the number 8 exhaust valve Is still open. The port manifold actually groups cylinders 5 & 7 together. Without a divider between these two cylinders, the exhaust gases from the number 7 cylinder will enter the number 5 cylinder when the number 5 exhaust valve Is still open. This Is not what we want. Using this style manifold on both sides of a V8 engine Is not very efficient. As shown on the Seaward manifold however, all ports are truly separated, leading to better exhaust performance.

*What can you expect from a new performance exhaust system*

A new Performance exhaust manifold and risers can provide feel of a noticeable improvement in the motors breathing much better as the engine(s) respond quicker to the throttle input, The risers stay significantly cooler vs the OEM risers it, and the water cooling temp is lower than before.

The combination of less weight on the rear transom area of the boat, with a faster response time to throttle input, quicker gas exhaust exit from the system and a cooler running system makes the boat perform better than before out of the hole and get quicker to chosen speed at all RPM ranges.

A very slight louder exhaust is only noticeable when flushing the engines out of the water, and a very slight deeper sound (more bass to it) exhaust under the water.

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Reviews On This Product:
(5.00)stars out of 5
# of Ratings: 1
1. on 7/26/2019, said:
5 stars out of 5
Installed this system on a Donzi 22ZX with a 430HP 502 engine, much improved hole shot, way better sound of exhaust and better top end. Great system and it includes everything needed for installation, be sure to order the brackets for the mercrusier Scott Price president of Hardin was vert helpful David
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Making selections in the following sections may change the final product price.

All Seaward manifolds come powdercoated for corrosion protection standard. With this option, an additional hydrogen infused zinc process is applied to each manifold for over 1000 hours of durability.



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