2004 280DA 496 Mag 8.1 Spark Plugs

[jpflhr]

So getting ready to tune up the boat and for the spark plugs it says MerCruiser part number 33–881673 which is now old Replaced by 33 – 863622. Which says it is a AC.- 41-983 plug Platium Performance Gap .059
i was reading and wondering if to go to a 41-993 which is Iridum Performance plug Gap .040
They say smother idle and better running?

Wondering what to do here the 41-983 is a little more priced also just want to put in best plug:smt001

Thanks
John

 

[juggernaut1]

I use Iridium NGK TR55IX's in mine and all good.

 

[Leardriver]

The 983 is the plug I use in my 2004 motorhome with the 8.1. It's not a finicky motor at all with plugs.

 

[Mittens]

AC Delcom. 41-983 plug Platium Performance Called for Gap of .060. and come with that gap in the box.

Raymar marine that builds 496 stuff like s.050 gap... but be SUPER carefull gaping this type plug.

I just did both mine and use .060 gap

 

[mnm99]

I'm using AC Delco 41-983 gapped at .060, Runs perfect...

 

[jpflhr]

Thanks you all looks like I probably stick with the 41 983