Is it normal that the exhaust pipe/cat under the car get so hot that they make a tapping noise after the car is turned off? I have a naturally Aspirated 91 convertible.

 

Yes its normal, its just from the heat, the pipes are cooling down and changing slightly - thats what the noise is.

 

that would be your catilytic converter cooling down, totally normal, alot of the new Jeeps do it even louder than the rx7 does

 

Every car i've ever owned and or drived has done this.

 

oh oh, this one time i heard someone saying it was "hot oil dripping from the engine to the cold oil in the oil pan"

i was like wtf wtf wtf??

 

Even our wood stove makes that noise when it starts heating up or cooling down. Completely normal, I am sure that it depends alot on the type of metal though.

 

Yes, I knew it was the temperature of the exhaust that was making it tap. I was concerned that the emission equipment was not working correctly and the car would crack something in the exhaust.

I have never seen another car do this but it is common for tim roofs.