You’ve finished installing your freshly wrapped headers and exhaust, but a few minutes after firing up the engine, you notice wisps of smoke coming from the engine bay and exhaust. You open the hood and nothing is on fire, but your freshly installed exhaust heat wrap is smoking like it’s going to catch on fire. Not to worry—this is actually normal for newly installed exhaust wraps that haven’t yet been exposed to heat.
Exhaust/header wraps are made with binders, which are specially formulated starches that give the wrap’s fibers some structure and lubrication during the weaving process. Once the manufacturing process is done, the job of the binders is complete, and when exposed to exhaust heat they tend to burn off, creating the aforementioned smoke after using exhaust wrap.