spark plugs

[johnboyy7]

04 210 with 343 pcm. how often do yall change plugs? and wires? does anyone have a preference on which plugs they use?

ive owned the boat for 2 years and i havent done it. boat seems to have plenty or power and runs good still.

[NCH2oSki]

My 05' with 343 still has the original plugs, 290 hours on it. Smells a little rich sometimes, so I'm planning on changing mine this winter. Per ski dim the iridium plugs ($99.00 per set) are what is used for the replacements. I've seen a few posts on here about people complaining they don't get but a season on the cheap plugs.

[ski4evr]

Hate to knock our supported vendors, but here are my plugs http://www.autozone.com/autozone/par...ier=186209_0_0_ . The '05 330 cross references to a 1998 vortec 350. WLM wants $97.50.

[Mikeski]

That would be a EX330 not a 343. I recommend the AC Delco/NGK Iridium plugs. The boat came with Platinum plugs and is probably good to at least 500 hours. My 2005 EX330 has 620 hours on it and will be getting new plugs this spring, the plugs are sitting on my workbench at home. I can confirm the number later but I believe they are AC Delco 41-101. I bought mine off ebay for a $40 for the set.

[NCH2oSki]

That would be a EX330 not a 343. I recommend the AC Delco/NGK Iridium plugs. The boat came with Platinum plugs and is probably good to at least 500 hours. My 2005 EX330 has 620 hours on it and will be getting new plugs this spring, the plugs are sitting on my workbench at home. I can confirm the number later but I believe they are AC Delco 41-110. I bought mine off ebay for a $40 for the set.

My mistake, thanks Mike, it is the EX330. The Iridium plugs is what I am also going to install.

[196 die hard]

So what is the AC Deco number for the EX343?

[Nordicron]

So what is the AC Deco number for the EX343?

I believe it is Ac delco 41-993

[Mikeski]

Correct the 41-993's are the correct AC Delco part number for the Platinum plugs, the iridium version of that plug is the 41-101 (not 41-110 as misstated in my earlier post (Fixed it. -Jeff)). I actually discovered I ended up with both a set of 41-993's and a set of 41-101's on my bench. If you are interested I will sell you the new discontinued platinum 41-993's I have for $45 shipped. I don't need both.

Note, these plugs are sometimes co-branded by NGK. The OEM plugs I pulled out of my mom's 2004 5.3L Tahoe were NGK's!

[NCH2oSki]

whats the difference in the Iridium and platinum plugs?

[johnboyy7]

whats the difference in the Iridium and platinum plugs?

i too would like to know. and whats the advantage of one to the other.

[Mikeski]

Iridium has a higher melting point allowing the electrode to be smaller, the smaller the electrode the better the spark, they iridium plugs also last longer.

quote borrowed from the internet:

"Size Matters
What does size have to do with it? Less voltage is required for a smaller center electrode and results in better ignitability. The smaller the electrode, the more centralized the electrical potential is around the electrode tip. The required voltage can be reduced because the level of the electric field is made stronger and local insulation (air gap and electrode surface oxidation) breaks down more easily. The bottom line is that it takes approximately 5,000 volts less to fire a Denso Iridium Power spark plug versus a conventional platinum spark plug.

So why not just make a smaller diameter electrode spark plug out of platinum? It just wouldn't last. The small-diameter center electrode reaches much higher temperatures. Iridium's melting point is 700 degrees C higher than platinum, and laboratory tests have shown that with the same-size electrode iridium, plugs were four to five times as resistant to wear as platinum. Much of Denso's R&D went into finding the perfect iridium alloy (90% iridium, 10% rhodium) that would provide 200,000 miles of service, and working out the manufacturing process to "draw" the electrode into the extremely small .4mm-diameter wire."

[NCH2oSki]

Thanks for the info!

So after reading the info that Mikeski supplied: what kind of plugs are you putting in your Nautique this winter?

[JayG80]

If I was putting plugs in a sports car with difficult access then I would install the expensive 200,000 mile spark plugs.

My GT-40 is so easy to work on so I use AutoLite 764 plugs for about $20 and change them more often. Boat runs great, new plugs at 200 and new plugs and wires at 500 hours.

Am I missing performance or is there another reason to pay for the expensive plugs?

[Mikeski]

If I was putting plugs in a sports car with difficult access then I would install the expensive 200,000 mile spark plugs.

My GT-40 is so easy to work on so I use AutoLite 764 plugs for about $20 and change them more often. Boat runs great, new plugs at 200 and new plugs and wires at 500 hours.

Am I missing performance or is there another reason to pay for the expensive plugs?

I can get the iridium plugs off ebay for $45/set so the extra $25 is money well spent to avoid changing them for 600 hours

[NCH2oSki]

If I was putting plugs in a sports car with difficult access then I would install the expensive 200,000 mile spark plugs.

My GT-40 is so easy to work on so I use AutoLite 764 plugs for about $20 and change them more often. Boat runs great, new plugs at 200 and new plugs and wires at 500 hours.

Am I missing performance or is there another reason to pay for the expensive plugs?

PCM does not specify the iridium plugs for the GT-40, the Autolite 764s are correct.