which sparkplugs??

[soda7o]

05 ex 400 lookign to replace sparkplugs
what are a good kind?

[GPracer2500]

NGK DPR8Z

[Big - D Racing]

or dpr9z

[soda7o]

thanks for th einfo but what is the diff between the two you suggested?

[bwamos]

Temperature Rating.

[soda7o]

Originally posted by bwamos
Temperature Rating.

sorry but i have no clue what that means?

[bwamos]

The DRP8Z and the DRP9Z transfer different amounts of heat back to the cylinder head.

You need the correct temperature rating. One that is hot enough to prohibit fouling of the plug, but cool enough to not induce detonation.

Generally you want to use the stock rating (except in a few cases).

The DRP8Z is a hotter plug than the DRP9Z.

Aka the DRP9Z transfers more heat from the combustion into the cylinder head. Less likley to remove carbon, bot also less likley to cause detonation. Detonation is where the mixture detonates uncontrolled before it is supposed too. Aka.. pinging.

If you are at the proper a/f mixture and getting detonation.. some times you can go to a cooler plug to stop it. Also if you're at the "proper" a/f ratio and fouling plugs, sometimes you can go to a hotter plug to fix it.

But, most of the time the stock rating is correct, and if your pinging, or fouling you're running to rich or lean.

Clear as mud?


Here's an article that may help some: http://www.ngksparkplugs.com/tech_support/spark_plugs/p2.asp?mode=nml

Also there's a spark plug finder on their site you can use to find the correct plug for your ATV.

[soda7o]

yes very helpfull