Spark plugs numbers

[redone 45]

Hi Guys. 

I am wanting to know the cross reference from Chapman spark plugs to NGK spark plugs.

The actual Chapman has a longer thread. As dose the NGK. I need the right plug number for

NKG.

Thank you

Bill

[pfrederi 18,333]

I assume you meant Champion but which number do you want to cross???

[953 nut 57,904]

I have always heard that you should look at the application chart for the specific manufacturer you are interested rather than a cross reference. 

[adsm08 2,644]

24 minutes ago, 953 nut said:

I have always heard that you should look at the application chart for the specific manufacturer you are interested rather than a cross reference. 

 

I would agree with this.

 

I have sold some plugs that were wildly wrong going only off a cross-referenced number.

 

The best part was that the guy showed up right after I closed, pissed off at me for getting him the wrong one, because all he brought me was a Toyota P/N, and no actual plug to compare mine to.

[gwest_ca-(File Mod) 11,243]

Spark plug cross references are only good to determine the physical dimensions of a plug. (wrench size, thread size and thread length)

Here is why.

Go to Champion and use their x-reference to determine which Champion plug would replace a "C" NGK plug. Result is a "8" Champion.

Now go the NGK and use their x-reference to see what NGK plug would replace a "8" Champion plug. Result might be a "D" NGK plug.

Same plug physically but a different heat range.

Only the company supplying the plug knows which of their plugs works best for the application. They don't test other manufacture's plugs.

 

The same with filters and Toro/Wheel Horse applications are a good example.

Wix will have a filter to replace a Toro part number but go to their application charts and they will recommend a different filter because they determined it does a better job.

 

Garry