NGK Spark Plugs...any good?

[ksubigbuck]

I always have a hard time finding the Champion Ql77JC4 plugs in my area. But, everyone seems to carry the NGK version. Has anyone tried them? Were the results good or bad?

Thanks,
Hunter

edit: Motor is a 1977 115hp

 

[tashasdaddy]

Re: NGK Spark Plugs...any good?

your motor was built to run Champion QL77JC4, not NGK. NAPA stores have the Champion.

 

[ksubigbuck]

Re: NGK Spark Plugs...any good?

Ok, thanks. I have a napa not too far from me. I'll get the champions.

Anybody want to buy some NGK's j/k

 

[Vic.S]

Re: NGK Spark Plugs...any good?

If you use NGK plugs in place of the Champion ones on a motor with OMC CD ignition then it is important to not to use the ordinary resistor plugs such as BR7HS which are sometimes given in application and equivalent lists

The OMC ignition system requires low resistance, inductively suppressed plugs if suppressed plugs are used.
The Champion Q series plugs are inductively suppressed!

The equivalent NGK plugs are the "Z" series to which end the NGK equivalent of QL77JC4 is BZ7HS-10 (although the -10 only indicates that it is supplied ready gapped to 1mm and you'll have to regap it to 0.7 to 0.8 mm , 0.030", anyway!)

Stick to the recommended Champion QL77JC4 but if you are forced to use NGK then BZ7HS or BZ7HS-10 are the nearest equivalents.

Technical explanation of the need to use inductively suppressed plugs rather than resistor plugs at http://members.iinet.net.au/~pauldawson/iame26-spark-plugs.PDF

 

[knehdn]

Re: NGK Spark Plugs...any good?

Interesting read... thank you.