I put the CSF in my twincam, that is the only direct fit welded race rad I could find. It seems to be a nice piece, fits properly, and eliminated the temp spikes I was suffering from. The car still runs hotter than I would like, but at least now it is stable at 220 on a 80 plus degree day, measured with a proper gauge, with the sender right below the thermostat. And that is running hard on a fairly fast track, using water with one jug of water wetter in the cooling system. Its back to 180 by the end of the cooldown lap.