How do you do a plug chop? I've been reading on the web but it seems there are different answers to this question(Must be like what kind of oil do you prefer) I've read that you need to run threw 2nd to 4th flat out then check it, another said top gear wide open for 8-10 secondsShould I warm the engine with the plug in it im going to test or use a old one to bring the engine up to operating temp?