Another 455 Spark Plug Q (pics)

[Bradf]

My boat was feeling a bit weak, and not running at the RPM it normally does, so i pulled the plug and here is what I got:
http://i22.photobucket.com/albums/b320/hadesgp/Plug.jpg
Thats a Bosch Platinum WR9FP (thats what someone told me to use)
After doing a quick search here on the forums, it looks as though thats wrong. What plug should I use? The boat has always ran a BIT on the fat side, but the plugs have never looked like that. Its a very mild motor. I cruise it at 3500-4k most of the time.
Here is the ignition:
http://i22.photobucket.com/albums/b320/hadesgp/IGN.jpg
^^ I have no idea what that is, it was on the boat when I bought it.
I appreciate the help guys, without these forums I would be so damn lost!

[gbelt]

I've never had good luck with those in anything except German cars. I'd go buy some AC Delco plugs.

[455Rocket]

Where are you gaping? Points or Box ignition?

[Bradf]

Where are you gaping? Points or Box ignition?
Sadly, I have no idea. Lemmie go pop the cap and take a look lol.
EDIT: It has points

[nyjetboat]

the coil is made by pertronix they are pretty good coils ,asfar as plugs go i use ngk R5670-5 you can get from jegs summit ect

[Bradf]

I can not find my damn plug gapper. I know the block is a 72 or 73 455. What SHOULD it be gapped at.. so when i go buy a new one lol. If the new plugs/gap setting doesnt have any effect, Ill prolly have to change the power valve (no idea how, which means ill take it to a shop)

[TahitiTiger]

I use AC Delco R45s, gapped at .060. But I use a MSD 6AL, I think originally they were gapped at .035. Also I would ditch the points, and if on a budget get your self a Pertronix Igniter. Reliable, cheap, and never fail. :D

[OverKill]

Yep AC Delco gapped at .035, that should do it.

[OverKill]

Oh and yes that plug does look a little lean. I might think differently if you were running 100LL AV Gas all the time.

[79centurion]

I think you mean rich. A good plug is tan/brown. That is too black. Ditch the platniums and put either delcos, autolites, or ngks in it.
Dan

[bakerjet]

if you idled the motor before you pulled the plugs then your not getting an accurate look at the plug, but when you do get the right plug. do a wot pass and kill it coasting to a stop then pull'em they should be clean with a color change at the bend in the ground strap and some light brown starting below the threads on the insulator (it looks like a ring). maybe someone will give you a link to plug reading its a good way tune.
Her ya go http://www.dragstuff.com/techarticles/reading-spark-plugs.html

[malcolm]

I like the NGKs too. I'm running them one range colder than stock.
How's it idle? Is it flooding? That will make 'em black.