Anybody know whether the ST215 COPs will fit on a Gen3 turbo head the same as the 1ZZ? Also do they operate the same with aftermarket ECUs? I know the 1ZZ work fine and are widely used， but I can more easily get a set of ST215 at the moment.
Do all COP just sit on top of the spark plug， and depend on a nut/bolt to secure them down? Or should they also clip onto/around the spark plug terminal similar to ignition leads?
The ST215 ones I've seen have the spring part cut across the middle， meaning they won't fit around the plug like leads. Probably better explained with a picture.
