It was the '99 Model year. They messed it up so bad they didn't have a 2000 model for the Cobra. They got it almost right in 2001 by increasing the compression ratio, among other things. Guess what, it caused pinging!!!!
They never did anything about it. I should know, I have one. It pings under load in 3rd. Not bad and not all the time. Some guys had melted/pitted pistons. Ford just handled them on a case by case basis. What subaru is doing is great!