Bumper Fire???? Exhaust Tips

[ProjectM96]

My new performance exhaust system touches the rear bumper. The tips are held up against the bumper pretty strong and it gets pretty hot since it is a high flow muffler.

Do I need to worry?

Is the gray part over the muffler tips made of aluminum or is that plastic. I cannot tell by feeling it or looking at it.

I have seen pictures of other cars whose bumpers caught on fire from exhaust.

Keep in mind that I will be driving it hard at the race track for 4 hours on Saturday. 1 hour breaks after each hour of driving.