I used to drive this thing all over NorCal but with a meager 6-71. It had iron heads and drove around on 9lbs of boost all day long on Cali pump swill. It did see as much as 20 a few times at the track on Sonoco 100. I can tell you the head gaskets were not long for the world like that. But this was the late 90's and if I were to do it again I think it could be made to love a bit longer now.