Stainless Steel Manifolds are ideal cast iron replacements, designed to eliminate leaking and corrosion. Lightweight. Custom made. Built to last the distance.

MarineTorq’s Stainless Steel Manifolds are a unique one-piece construction, designed for petrol and diesel inboard boat engines. Built to prevent engine failure, boost performance, and improve fuel efficiency.

A manifold collects and cools the hot exhaust gases as they are expelled from the engine, while simultaneously allowing the cooling water to exit. It is an integral part of your boat, which has to withstand extreme temperatures, water, vibrations, and corrosion. For cast iron manifolds, this combination is a ticking time bomb.

The average lifespan of a cast iron manifold is 2-3 years. There’s no obvious warning light for manifold failure, so unless the manifold is replaced regularly, you could be facing irreversible and expensive engine damage. In comparison, a quality stainless steel manifold can potentially last the lifetime of your boat.

Why Choose Stainless Steel 

Our Manifolds are made from premium quality stainless steel. Here’s why…

  • Stainless steel is very lightweight- a MarineTorq manifold weighs only 7 kg on average. In comparison, a cast iron manifold can weigh upwards of 50kg. This means stainless steel will reduce the dead weight by up to 80%!
  • Cast Iron manifolds typically corrode with a blistering action, leaving layers of rust which block water flow and speed up the corrosion process. MarineTorq’s stainless manifolds include a sacrificial zinc anode, which prevents a build-up of rust. This means better performance, plus less time and money spent on replacements!
  • The thickness and grade of stainless steel used in MarineTorq’s manifolds has been extensively tested to prevent cracking or brittleness under extreme heat and pressure. Capable of withstanding 650-700 horsepower, the quality and longevity means we can offer a much longer lifespan and warranty period than cast iron manifolds.
  • Stainless steel is as beautiful as it is functional, the workmanship and eye-catching finish will make your engine bay a conversation starter! Compared to rusty cast iron, a shiny set of stainless manifolds are worth showing off.

Our Most Common Questions

Do Stainless Steel Manifolds Rust?

No, MarineTorq’s stainless steel manifolds won’t rust and here’s why. Each manifold includes a sacrificial zinc anode which when replaced regularly, keeps the manifold in perfect condition. We recommend checking your anodes every 3 months, and replacing every 6 months to maintain the manifold warranty. Learn more about how anodes work.

Freshwater vs Saltwater Manifold Lifespan

In freshwater, we are confident our stainless steel manifolds will last the lifetime of your boat. With regular anode replacement, MarineTorq’s stainless manifolds will also last indefinitely in saltwater. In one instance, a set of manifolds have been on a customer’s boat (in saltwater) for 20+ years. For more on maintenance and replacement parts, click here.

Lifespan of Stainless Steel vs Cast Iron

The average lifespan of a cast iron manifold can be as short as 2-3 years, and regular maintenance/ replacement is a non-negotiable for avoiding engine failure. In comparison, MarineTorq stainless steel manifolds have been proven to last 10+ years, offering better long term value and less time in the workshop. Find out more on the benefits of stainless steel vs cast iron.

When Did You Last Check Your Manifold?