Best spark plugs for a 318

[gran coupe john]

Just looking for best spark plugs for my 318 71 gran coupe

 

[Chryco Psycho]

IMO Champion & Autolite regular , platinum or irridium .
But everyone else will tell you NGK which foul & quit firing all the time

 

[gran coupe john]

Automated was in it, but 20 years ago. Thanks I respect all opinions.

 

[EW1BH27]

I’ve run NGK GR4 V-Groove since 2011 with absolutely no issues or problems.

Whether it makes a difference my 318 is bored 40 over, mild cam, LD4B intake, 600 CFM Holley, 340 6pk exhaust manifolds, 2 1/2 inch TTI dual exhaust, Mopar Electronic Ignition.

 

[Xcudame]

Champion. I figured Ma Mopar used them as factory for a reason. The regular copper plus are still pretty cheap, and changing them every 10,000 miles or so helps milage and performance.

 

[tonysrt]

The only reason Ma Mopar used them was because they were the cheapest. I'm not saying there bad, just cheaper than any others. I run RC boats with Zenoah engines and the first thing we do is throw the Champions away and use NGK. The Champion electrode is weak and has a tendency to break down or off and ruin the engine.

 

[Xcudame]

Sorry, got to go out on a limb and disagree with you! I've fixed many of crappy running Mopars just by throwing away other brands of spark plugs and putting in stock copper plus Champion spark plugs! Realize NKG are Japanese plugs!!!

 

[tonysrt]

I didn't say they were bad just lower in price than others. In our Zenoahs they weren't physically strong enough to with stand the punishment we put them through. Full speed as soon as were in the water for 3-4 minutes.

 

[Xcudame]

Hince why I replace the Champions often!