Ideal coil on plug spark plug to suit 20v

[4.5AG]

http://184.72.239.143/mu/8ba8c976-2135-f511.jpg
Denso PK20PR11
http://184.72.239.143/mu/8ba8c976-1fb3-ced6.jpg
This was taken off my engine after racing on the weekend.
The engine misses above 6000 rpm on all gears after a few laps, it was
suggested to use colder plugs or iridium type plugs.
Any suggestions? Has anyone used Denso IK20.
cheers,
Vener

[Sam-Q]

what do you mean by the "coil" in your thread title?

[Anthony]

its pretty hard to diagnose plugs when the pics are out of focus but the colour doesnt look good :)

I only use NGK iridium BKR6EIX-11

[4.5AG]

what do you mean by the "coil" in your thread title?
I was referring to 1zzfe coils
The plugs tip looked rusted after taking it off.I'll try to get some clear pictures tomorrow.

[Sam-Q]

just a bit ocnfused, the thread title sounds like a question about the most ideal 20v coilpack but your content is about plugs

[PRIMRK]

i think he means what is the best spark plug for a COP setup...maybe...

[H8CHIR6KU]

yeah man that plug looks rusted. bhg?

id be pressure testing the cooling system with the plugs out for a while then crank it over and see if water comes out.

[4.5AG]

i think he means what is the best spark plug for a COP setup...maybe...
Yep that's what I meant..yeah the plug looked rusted, there is no coolant lost during the race.

[macca1590]

http://www.verrill.com/moto/sellingguide/sparkplugs/plugcolorchart.htm

cant realy match any one up to urs with that pic quality thoe