Computer Chip

Hi all, new to Porsche. I have a 84 911 Cabriolet-was told the chip was replaced with a high performance one, but I can't verify other than what previous owner said. I found under the drivers seat Bosch silver box with a wiring harness going into it and 4 screws holding a black female end. Silver box looks sealed, how do I tell for sure?

Would I gain performance by going with aftermarket chip and if so what one?

Rgds/Brian

To verify, you will need to open the box and check to see if the chip is changed, most likely to Autothority imprinted on it. You can try to test and see if the redline is higher. Chips raise it around 500 rpm from stock.

------------------
8 9 9 1 1, The last of the line.