spark plugs

[novi306]

what is the best plug for windsor sr. cast iron heads i have tried ngk and autolight plugs when i tried to cross reference at the local parts store they suggested autolight 23's ,runs very rough with these ,they did not have any one step colder. The ngk's were # 7's . Plus with an ignition such as an MSD is plug gapping as critical? "they" recomended setting the 23's at .50 stock gap,but it doesnt idle as crisply as before .

[speedytang]

Autolite #24 and .035 gap.

[novi306]

do i need to gap it at .035 with an MSD ?

[speedytang]

More than likely YES. In supercharger application opening the gap does nothing for performance and even with a MSD the spark will blow out.

[novi306]

changed gap settings back to .035 runs and idles alot better, thanx for the info

[speedytang]

Welcome

[regattacoupe]

what is the best plug for windsor sr. cast iron heads i have tried ngk and autolight plugs when i tried to cross reference at the local parts store they suggested autolight 23's ,runs very rough with these ,they did not have any one step colder. The ngk's were # 7's . Plus with an ignition such as an MSD is plug gapping as critical? "they" recomended setting the 23's at .50 stock gap,but it doesnt idle as crisply as before .

What is the full part number of the plug? I'm running these same plugs on my 393 but they are not gasket plugs. They are tapered seat.

[novi306]

checked, what they gave me were the 26's.. never looked that close at them when i put them in ....

[NOVI VERT]

Are autolite 3923's too cold for 9-10 pounds of boost???? Or should i move up too 3924's????