My z31 drives fine when out of boost. But when I was driving it today I went into 3rd and did a pull and when it got into boost at about 3psi it starts to miss out bad. The spark plugs are at .026 and the rotor and cap are new. timing was at 20. And at wide open it was at 10.5:1 AFR. Any ideas what could cause the miss out?
Try using some di-electric grease on the spark plug wire connections. It reduces the resistance towards the electrons as they cross over from one metal to another, therefore allowing more spark to reach the spark plugs. Also, check your grounds and make sure they are secure and clean.