Spark plug difference

[SweeperForce]

I've been using NGK BUHW for the past 2+ years with no problems. However on NGK's website they suggest I use BUHX. I seached for a while on the web and can't find any difference between the two. Can anyone on here give me a hand?

Thanks,
Tom

 

[Jiggz]

Re: Spark plug difference

The BUHX is a booster type plug requiring higher voltage to fire than the BUHW. For Force engine always recommend using the rugged voltage BUHW.

 

[pnwboat]

Re: Spark plug difference

As Jiggz stated, the NGK BUHX is s boost gap plug. There is an internal gap inside the spark plug. If you take an OHM meter and measure between the center electrode to the metal tip that the wire attaches to, it will read "Open". No continuity. This type of plug was designed to allow the voltage to build up to a certain point before it fires. Early CD ignitions systems (Prestolite) use this type of plug to insure adequate spark energy. Spark plug gap is factory set to about .025".

The NGK BUHW is a non-resistor standard type plug. If you measure resistance from the center electrode to the metal tip that the wire attaches to you will read 0 ohms resistance. Basically the same as a piece of wire. Later model CD ignition systems ( Mercury Thunder Bolt) use this type of plug. Spark plug gap is factory set to about .045".

Here is a picture of the two types of plugs. BUHW on the left, BUHX on the right. Notice the gap from the center electrode to the body. It's wider on the BUHW than the BUHX.