What spark plug to use for WOT?

[ericthered]

Hi all,

Just got the jetting sorted on my GP200 and would like to know what spark plug I should be using if going on a decnt run out and using wide open throttle a lot? Not motorway as such but decent A roads.

Its a SIL GP200 with AF clubman, standard indian stage 4 barrel (but with inlet and exhaust matched to barrel and internal casting faults removed but not polished), 22mm Jetex running 130 main and 48 pilot, and drilled airbox.
Been using an NGK B7ES.
Should I be using B8ES for long runs??

Thanks and regards,
Eric.

[Rally220]

B7ES for round town, B9ES for long runs.

[ericthered]

Thanks Rally220, I'll give that a go.

[Burnside]

Stick a B8ES in, it'll be fine for round town and long runs, shouldn't need a B9 for a standard setup

[ericthered]

Thanks for that.
I called AF Rayspeed to order one and they said they prefer Champion as Ray thought he lost up to 500rpm (at max rpm)running an NGK.
Anyway, getting an N4 and an N3 (N3 same as B8ES I think), going to use the N3 for all round use and long runs and keep the N4 for back up.
Best regards,
Eric.

[shocky]

Thanks for that.
I called AF Rayspeed to order one and they said they prefer Champion as Ray thought he lost up to 500rpm (at max rpm)running an NGK.
Anyway, getting an N4 and an N3 (N3 same as B8ES I think), going to use the N3 for all round use and long runs and keep the N4 for back up.
Best regards,
Eric.

Really never heard that before

[speedy]

There were folk who said that NGK worked best in Vespas and Champion work best in Lammies. I have no idea if this theory is true or not,however, I do use this system myself, I don't know why, but I do . I also used to like Nippondensu ZU plugs, but they are harder to locate. Think it's just personal choice really.Cheers,Speedy.