# 1970 GTO Judge spark plugs



## tklaxs119 (Sep 29, 2012)

I have 46S AC spark plugs. But I think I need R46s spark plugs for the 1970 GTO JUDGE. Which is right? 

Does anyone need a pair of R46 spark plugs if I do indeed need the R46S?


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## geeteeohguy (Feb 2, 2008)

"R" stands for resistor. Either plug will work. The resistor plugs were designed to eliminate radio interference. But most ignition cables have built in resistance, which helps. It's all about electronic noise repression. Other than the resistance factor, they are the same plug.


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## tklaxs119 (Sep 29, 2012)

Which was original?


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## geeteeohguy (Feb 2, 2008)

R45s was original. R44s if it was/is a ram air car. Resistor plugs came standard starting the 1969 model year. Pre '69's had the non resistor plugs. Performance 400's and 389's used the 44S plugs, 2bbl versions the 45S. In '70, the heat range went up slightly, to R45S. R46S plugs are hotter, and meant for lower performance 2bbl engines.


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