Whether you realize it or not, there’s a method to the madness behind what material is used on the exhaust parts on your high-performance car. Stainless steel is more than just jewelry for your ride–it adds some wonderful benefits to the entire exhaust system that add performance that you may not realize.
Vince Roman from Burns Stainless provides some knowledge that will broaden your understanding of this mystical metal, and why you need to use it when you can.
There are really two stainless steel alloys that are the most commonly used in motorsports: 304SS and 321SS. The 321SS alloy tends to be stronger at higher temperatures that you see in the extreme environment of racing, so it naturally is the choice for turbocharged and other high-heat applications. The manufacturing specification of the steel is important because of how it can be manipulated. Burns Stainless works with a minimum ASTM 249/269 spec because it makes the forming of tubing easier without it splitting for fabricators as they build exhaust components.
Stainless steel has a much lower carbon content and higher amount of chromium, which makes it resist corrosion better and possess a higher level of strength. According to Roman, there are three major characteristics that make stainless steel the ideal choice for exhaust systems.
“Stainless steel has a higher strength than mild steel resulting in a more robust exhaust and allowing for thinner-walled tubing to be used for reduced weight. Stainless steel is considerably less prone to corrosion, allowing for a long-lasting exhaust in spite of high-temperature operation. The lower thermal conductivity of stainless steel as compared with steel minimizes heat transfer to the engine compartment, reducing high-temperature exposure of engine components. Also, this keeps heat energy in gases helping to scavenge the exhaust.”
Now you see why all of the high-end exhaust systems and headers on the market use stainless steel for their construction. If you’re looking for more information on stainless steel, or need some for your next project, make sure to check out the Burns Stainless website.