anyone used one of these ?

I have not used one. They may work to keep an aluminum header in a sport boat cooler, but for a tuned pipe system to work to its potential ( why we use tune pipes to begin with ), we want to build as much heat in the exh. as we can. So from a performance stand point, we need to keep heat IN the exh., and keep heat away from the carb. Stainless headers and ceramic coated pipes, together with plenty of fresh cool air for the intake, is a good recipe. However, they may help to solve heating issues on sport boats with aluminum headers/pipes.

Where did you find that ?

www.horracing.com/product_info...lqb4679hgon3t87

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