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Cylinder Head Gasket - Volvo

Head Gasket
Your Price:

Head Gasket


Key Features:

  • For: GM 305 (5.0L)/350 (5.7L) CID Eng.

Additional Details:

  • Fits: MCM/MIE GM V-8 (283, 305, 327, 350 & 377 cid) engines

Use With:



  • 16.50-00250


  • 7057500


  • 36160


  • 6269577


  • 9-63706

Mercruiser Stern Drive

  • 27-34278
  • 27-48330
  • 27-75611
  • 27-75611001

OMC Stern Drive

  • 313201
  • 3853380
  • 910089
  • 914971

Volvo Penta

  • 3853380
  • 841207
  • 856474

Max Volt Catalyst Eliminator Computer
Starting From:
This Part has options, please click the button below to order.

Max Volt Catalyst Eliminator Computer

121-120 + Option(s)

Max Volt Catalyst Eliminator Computer

If increased engine performance is what you are after but have concerns about the catalyst equipment on your engine, then the Catalytic Eliminator Computer (CEC) is what you need! Designed specifically for marine engines, Maxvolt Performance worked with a team of marine electrical engineers to create a product this simple and gets the job done. There is no cutting or splicing of wires; everything is plug and play! And there are three ways to play! Your engine can be Aggressive,Mild, or Basic:

Aggressive: If you want to be aggressive and replace your stock exhaust system with a header system, then this is the product for you. We worked with the header design teams at Hardin Marine and other popular manufacturers to be sure their headers are manufactured to work with CEC. To be compatible, the header must be made to accept a pre-oxygen sensor!

Mild:If changing over to headers is too aggressive for you, then removing the catalysts but retaining the stock exhaust manifolds is the path for you. Depending on the engine, 10 to 15 horsepower will be gained by removing the catalysts and using the factory exhaust system.

Basic:If your boat has fouled its post oxygen sensors and is no longer under the factory warranty, then you know what it costs to have new sensors installed and the trouble codes cleared. For less than what your dealer charged, you can purchase and install the CEC and never have to worry about throwing that fault code again!

  • Only works with the 4 pin plug switching style O2 sensors.
  • Will not work on the newer wide band O2 sensors with 6 pin plugs.

WARNING! This module is not to be used on emissions regulated waterways. The intent of this module 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 computer system is not legal for any purpose other than testing purposes and not for use on any state or federal waterway.

O2 Spacer, Stock Mercury Riser
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O2 Spacer, Stock Mercury Riser


O2 Spacer, Stock Mercury Riser

This Unique 1" thick adapter plate provides an installation option for retro fitting a Oxygen sensor and or air fuel ratio gauge for tuning purposes Into Mercruisers most common Wet Joint style exhaust manifold systems. The part is CNC machined from 6061 Billet Aluminum then Naval Spec Hard Coat anodized for corrosion resistance (Beware of inferior non-coated versions)

A unique feature of this adapter is the cooling parts that run along each side of the sensor maintaining consistent temperature of the spacer. Designed to accept all popular 18MM O2 Oxygen sensors.

  • Mercury 3 and 4" Riser Gasket(700-32080) 2 Required
  • Stainless Steel 18MM Oxygen Sensor Plug(620-50031) 1 Required

TECH NOTE: Will O2 Sensors Work In marine exhaust systems?

YES FOR TUNING but they have limitations as water / moisture is a byproduct of combustion. Often boaters find there is moisture in their exhaust system that have collected or made their way inside of what is better known as the "DRY" exhaust stream of their exhaust system. Anything from steam like to little water droplets about 1/32" all around the inside of the exhaust. This is because water IS a by product of combustion. same thing you see on a cold morning behind cars. sometimes you see water dripping out.

Don't take our word for it ask a real rocket scientist:

This is why O2 Sensors are great for tuning but have a limited long term life span unless protected by Catalytic converters like on New Marine engine offerings. So you know gas is known as a hydrocarbon based fuel. And we all know what hydro means WATER.

Seaward O2 Oxygen Sensor Adapter Flange
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Seaward O2 Oxygen Sensor Adapter Flange


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.

Stainless Steel Oxygen Sensor O2 Bung
Your Price:

Stainless Steel Oxygen Sensor O2 Bung Installed


Stainless Steel Oxygen Sensor O2 Bung Fitted to Tailpipe (Each)

These bungs are designed to allow you to weld in an oxygen sensor bung for convenient fuel injection or air fuel ratio calibration.

Universal M18x1.5 thread pitch. Fits most wideband & narrow band O2 sensors. Requires welding.

Note: This part will be fitted to Hardin Marine tailpipes. These must be ordered with Hardin Marine tailpipes. It does not include a plug, see related parts if you need a plug.