engine misfiring

[malder]

since I rewired my Z it is running really poorly. It misfires very badly when cold and is only slightly better when warm. The power band totally goes flat at about 3000RPM. Timing is @ 7degrees. My mechanic friend and I were moving the timing around yesterday and it only improved slightly...I have the Pertronix ignition. I know the carbs aren't tuned to perfection, but I don't think it should run as poorly just because the carbs aren't just right.

My friend recommended I should start by getting some new spark plugs and then we can start narrowing it down and get it running smoother.

Any suggestions for where we should start looking for the problem?

:classic:

[beandip]

YES ! Fix one thing at a time ! if you do change plugs use only NGK they work the best in these Zs trust me. Just the standard ones no platnum. Is the engine backfireing? or just missing under load. For now concentrate on when the engine is warmed up for any testing . All cold engines will act up when cold. 1st . did this all happen since you worked on the wireing? If so what did you do ? look there. 2nd look inside the dist . cap and clean the contact free of any crud and see if they are burned same for the rotor. If a dist with points check to see if they are pitted or have a spike . if either replace them. and the condencer as well. When at idle does the engine misfire? if it is missing put on some gloves and remove a plug wire and see if the engine changes speed . do this one at a time the bad one the engine will not change speed. If you find one that seems bad , try this plug in a different cylinder and see if it still missfires. You could have a bad plug wire. I agree it sounds like ignition especially since you said it was missing. Also check the vacume advance if equiped with one. I hope you are aware that just because the temp gague says the engine is warmed this may not be the case . It takes a while for the engine to properly warm up so have patience here. I dont know of your experience level. Its 1:30am time for bed . Good luck