Just realized exhaust wrap isn't always better than a heat shield

I used to wrap every header I touched for years, but after my 2005 Mustang cracked a manifold last summer, I went back to a ceramic heat shield and the underhood temps dropped more than I expected. Which do you guys run on high mileage daily drivers, wrap or shields?

3 comments

3 Comments

keith11619d ago

Right, that moisture trapping is the real killer with wrap on a daily. Once it soaks in and sits against the pipes through a few cold starts, you're basically begging for rust to eat through from the inside out.

stone.sarah20d ago

Yeah "underhood temps dropped more than I expected" is exactly what happened to me too. I had a 98 Jeep Cherokee that I wrapped the whole exhaust on and thought I was being clever, but after a year the wrap was frayed and holding moisture against the pipes, plus my intake temps actually went up on hot days. Swapped to a basic aluminum heat shield over the manifold and the difference was night and day, engine bay felt cooler to the touch and the truck stopped pinging on 87 octane. I think wrap works great for race cars that see fresh air and high heat cycles, but for my daily that sits in traffic and gets driven year round, shields just make more sense.

shah.evan19d ago

Intake temps actually went up on hot days"? Wait, hold on. You're telling me your intake was pulling in hotter air with the wrap on? I gotta admit I never checked that on my old project car. I just assumed wrap was keeping everything cooler overall. But thinking about it now, if the wrap is holding heat in the pipes and that heat radiates back up into the engine bay instead of escaping, yeah I could see that making the intake air warmer. That's kind of a game changer for me honestly. Might have to rethink my whole setup this summer.