People could sit around and debate that kind of Porsche Piwis Tester II question all day long, with good points being brought up on either side... however, whatever the outcome of that debate, it would be completely meaningless to your issue. The real question here is "does Farmer's Insurance Company consider the normally aspirated version of the Porsche 944 to be 'high performance."

To get the answer to that question, ask Farmer's (better yet, ask for a quote - that will Porsche 2 tell you pretty much exactly the cost regardless of what they think of the performance, since the cost of insurance on a car that old will be mostly affected by the history of their costs insuring these cars).