All of the top of the line 1970 A bodies ran mid 13's stock on crappy tires and through manifolds and smog tuned carbs. They were mass production but expensive for what they were just like the Evo and STI. I think its a little harder to wring more power out of an STI or Evo than it was to get it out of one of those muscle cars because the 4 cyl cars already have a lot of trick parts on them, while the stock muscle cars have a lot of room for improvement.