Muffler Exhaust Manifold Wrap

Why?

 

Drag racers wrap their headers....it increases power slightly since they act as vessels for the exhaust and keeping the heat in the vessels make more power. A better thing is to have them ceramic coated. After a dragster makes a pass you can actually touch the header and it will only be warm! On some cars this works better, depending on motor design. On the old 2.2 and 2.5 motors that Chrysler made they work GREAT! The motors have the intake and exhaust on the same side of the motor so the better they flow heat away from the intakes the more power they make.

So that is one reason to do it. I would think that this would also create more mpg too!

 

To elaborate, it keeps the heat out of the engine bay. Simple thermodynamics... engines are most efficient when they take in colder air and expel hotter air!

Another benefit might be that the cats run hotter, leading to fewer emissions... but that's debatable.

Either way, go with the ceramic coating over the wrapping. More bang for your buck... it's cleaner, more durable, and doesn't eat up space in your cramped engine bay.

This, not so much. O2 sensors don't measure temperature. Once your cat has warmed, your ICE is going to cycle the same with or without a wrapped exhaust.

You don't need to replace the sensor until it fails (if it does)... your ECU will tell you when it's time. It's a waste of money otherwise.