I read somewhere that the Porsche ECUs are pretty delicate. I'm putting on the AWE CATs this week and I think there are two ways to have the ECU remap to the change. The quickest is to disconnect the battery (black first both to disconnect and reconnect from what I read), but this can lead to power spikes that can fry the ECU. Is it safer to just drive the car and eventually the ECU remaps? How long do you need to drive it? How many miles?

 

I don't believe that a simple disconnect and reconnect of the battery, to reset the ECU, puts anything in the electrical system at risk. So long as you're careful this is the way I'd proceed. The process will accelerate the 'learning' of the new exhaust behavior - enabling you to more quickly identify the change, if noticeable at all, from the previous setup.
Considering that these are street cars, designed to have batteries replaced, jumped for starting and all of the other electrical issues that come with long-term ownership, by people who are not necessarily as skilled as those on the Porsche factory race team, it's the path I would take - and do take every time I make a change.

 

I was reading on another forum where a guy did the battery disconnect thing and the ECU went bad. He eventually took it to the dealership and wrote in his thread that the dealer said its fairly common for the ECU to go bad when changing a battery b/c of the spikes in power. However, I only read that once, so it's anecdotal information for now.

 

I disconnect the negative terminal on my battery all the time, and it's never been a problem. A few hrs is all you'll need. Enjoy the AWE cats, they're terrific!
CATTMAN

 

Likewise, I've disconnected/reconnected my battery more than a half dozen times and no problems.

 

Same here, no problems at all besides the average mpg resetting.

 

I disconnect the negative battery terminal every time I change a part of the intake/exhaust equation or whenever I changed anything with an airbag. Never a problem.

 

is it neccesary to disconnect battery to "learn" new characteristics or will it do it on itself?