[javadog]

If you are talking about an ignition distributor, there were several different ones used for the 911SC. In general, US and "Euro" cars had different ones. Likewise there were those used in '78, '79 and '80 and different ones from '81 onwards. Obviously, the differences are in the advance curves. As ruf-porsche mentioned, the rev limiter was done differently on some cars.

If you are talking about fuel distributors, then you also have a bunch of different ones used. The main difference related to whether the car was fitted with an O2 sensor or not. There were differences from market to market and year to year. Porsche changed something or another in the injection system every year.

All this is to say that, maybe you have more power as a result and maybe you don't. What would concern me more is if you have more ignition advance and are subject to getting a little detonation as a result. It's hard to hear it if it occurs in these engines, particularily if they are new to you. An '83 SC had lower compression in the US than Europe, but it was quite a bit higher than the first few years of SC production. I'd be real curious to know which distributor was installed and what timing the car had.

Whenever I buy a new (used) car, I take a careful look at what previous owners have done. I find I undo more modifications than I keep. I don't want to make you nervous unduly but I always suggest a good shop take a look at the car as early in the ownership process as possible.

Happy driving, and welcome to this asylum...

JR