My bumper is really hot

[Bighim]

I'm a Chevy guy and bought my first 911 about a year ago, a 1988 911. I took out for a drive today, air temp around 70 degrees, car running very nice, drove around 35 miles. Pulled in my garage and check under car for leaks after my ride and the rear bumper was too hot to leave my hand on it for more than a second. I shot the rear bumper under the backup light with my infrared heat sensor and got 126 degrees on drivers side, passenger side 115 degrees. The muffler itself was 227 degrees and cat was 304 degrees.
So here's my question, is this what is considered normal? The muffler is stock and sits only a few inches away from the bumper just like any other 911. Any ideas?
Thanks.

[McLaren-TAG]

Perfectly normal.

[porsche930dude]

If its ok in your area replacing the cat with a bypass pipe helps alot with lowering temps down there and easier access to valve adjustments

[Joe Bob]

Do you know how to check the oil on a dry sump motor?

[Pazuzu]

Originally Posted by Bighim

I'm a Chevy guy and bought my first 911 about a year ago, a 1988 911. I took out for a drive today, air temp around 70 degrees, car running very nice, drove around 35 miles. Pulled in my garage and check under car for leaks after my ride and the rear bumper was too hot to leave my hand on it for more than a second. I shot the rear bumper under the backup light with my infrared heat sensor and got 126 degrees on drivers side, passenger side 115 degrees. The muffler itself was 227 degrees and cat was 304 degrees.
So here's my question, is this what is considered normal? The muffler is stock and sits only a few inches away from the bumper just like any other 911. Any ideas?
Thanks.

Wait until you touch the passenger side front fender after a 35 mile drive...


Or better yet, drive through a small puddle and get steam billowing out from the wheel well!

[group911@aol.co]

Make sure the heat shield is still under the reflector area

[tobluforu]

and if its not, either buy one or you can line the inside of the bumper with reflective heat tape.

[Mike Andrew]

JC Whitney sells a nice adhesive backed foil covered insulation that can be cut to fit this area. Do not have temp data but it definitely drops the temp of the bumper and reflector area. IIRC, it was about $25.
Yeah, yeah, I know - JC Whitney??????

[rfloz]

Or:

[bkreigsr]

[Flojo]

You don't want to plastidip that area, haha

[Bighim]

Info has been helpful, I was concerned the temperature was abnormal.
I gather that all is okay and I should expect the temp of the bumper will go up as the weather warms up.
Hope it doesn't damage the paint on the plastic bumper but then again, I guess they all run this hot.
I'll try the heat shield for piece of mind. I've wrapped headers with the heat tape with pretty good success. More ideas are welcome.

[allaircooled]

There is supposed to be a heat shield there? ooops.. I don't have one.

[Jerome74911S]

The original post asked about the rear bumper. It is made of aluminum, not plastic. The valance below the bumper is steel. Not to worry.

[75 911s]

My bumper got so hot it melted the holes closed and burned off the paint...

[Bighim]

Whatever the back bumper is made of, it gets really hot.