Timing chain questions

[Decolliber]

Does the 911 have an interference engine? Do timing chains ever need to be changed? Do they break? When I first got my Carrera, a Porsche dealer service manager (Lujacks, Davenport, IA) tried to persuade me that I should get new timing chains at 60K, for a mere $1300. But since it was not listed in Bentley as a 60K service item, I declined.
Timing belts have been on my mind since I saw a '95 Audi A6 at the local dealer having a $3500 top end rebuild because the timing belt broke at 73K. So I promptly had my A6's timing belt replaced at 55K.
So then I asked local Ford dealer if my wife's 97 Escort has an interference engine and he says yes, and change it at 60K. Then I read in Chilton that it does not have an interference engine. So I figure, what the heck, just wait until it breaks. Does a broken timing belt do an harm in a non-interfrerence engine?

[ChrisBennet]

The 911 has an interference engine and a timing chain. No need to change the chain until you rebuild the motor.
-Chris

[rcwaldo]

becareful on the escort, get that belt changed--a tow truck ride might cost you more than the timing belt....

[Superman]

A broken timing belt on a non-interference engine does no harm, except that the car won't run until a new belt is installed. A broken belt on an interference engine means that one or more valves will be bent. Sometimes all the valves, or at least all the intake valves. So you see, timing belts are a good investment.