I changed the spark plugs and I am freaking out. My leading look really really really bad. I searched but no concrete answer. what it could be detonation, worn out or fouled.? Both are 9 heat range. Fd is pushing 320- 350whp. Any help would be appreciated. Left leading, right trailing.

 

Colour doesn't look too bad.

Do the deposits just brush off?

Looks fairly normal to me.

The trailing plug always looks "better" because the trailing plug hole into the rotor housing is much smaller and the plug is exposed to a lot less abuse.

 

The leading plug has some hard stuff, it might take a good amount of effort or wire brush to get it off. I have a new set of plugs, but I was worried that something really bad was going on.
Thank you sir..

 

if that's both lead and trail its normal.

 

The one with more deposit is the leading and the other one is the trailing. The rear housing's plugs show the same case as thisones. I don't have any smoke coming from the exhaust.
Thanks

 

Thanks for you help..as always my respect for you guys..

 

The center electrodes look fine and the ceramic doesn't look like it's damaged judging by the pictures. To get some of the harder deposits off you could lightly sandblast the tips of them.