premium spark plugs

[lakegeorge]

Has anyone tried any premium spark plugs, like Iridium or something similar? If so what were the results. I'm curious as to what the results were as they claim a lot of things on the net.

 

[lakegeorge]

premium spark plugs

I'm posting this in 2 areas to see what you guys think. Have any of you tried any premium spark plugs? I'm thinking like the Iridium plugs and if so what did you notice?
Most major plug companies offer them.

 

[bruceb58]

Re: premium spark plugs

I'm posting this in 2 areas to see what you guys think. Have any of you tried any premium spark plugs? I'm thinking like the Iridium plugs and if so what did you notice?
Most major plug companies offer them.

Waste of time in a boat. You typically are replacing plugs before they ever wear out.

 

[Bondo]

Re: premium spark plugs

I'm posting this in 2 areas to see what you guys think. Have any of you tried any premium spark plugs? I'm thinking like the Iridium plugs and if so what did you notice?
Most major plug companies offer them.

Ayuh,..... Anything other than the spark plug stated by the manufacturer at the time it was built is a Waste of gas money....

SBC's, 'n most other Chevy based motors, up to 'bout '96 would be the AC Delco, MR43T...

'n Don't post in more than 1 forum,...
When I find it, it's comin' here...

 

[sktn77a]

Re: premium spark plugs

Unless the engine in question is designed to run long-life platinum or iridium plugs, you won't see any appreciable benefit. Platinum plugs are designed for roughly 1000-2000 hours use and iridium for 2000-4000 hours use in a car. In a boat, however, you won't see that kind of longevity.

 

[jestor68]

Re: premium spark plugs

Has anyone tried any premium spark plugs, like Iridium or something similar? If so what were the results. I'm curious as to what the results were as they claim a lot of things on the net.

The so called premium plugs only advantage over standard copper core plugs is longevity. If you have ever dug around in some of these cramped engine compartments trying to change plugs, you will appreciate not having to do it so often. Since the service life is more than double that of a cheap plug, you won't have to change plugs but every 10 years or so.

As far as the specialty plugs like SplitFire goes, I have seen tests showing slight improvements in power and fuel economy. But the difference was so little that I found it hard to justify the price.

 

[bruceb58]

Re: premium spark plugs

Since the service life is more than double that of a cheap plug, you won't have to change plugs but every 10 years or so.

To me, this is a bad idea in a boat. If you have any possibility of any corrosion, you could have a very stuck spark plug.

 

[rallyart]

Re: premium spark plugs

I've actually run dynamometer tests on race engines with different spark plugs and different wires. There are differences but they are tiny. (i.e. 0.74 hp on 300) Plugs with multiple prongs offer more flame opportunities but the extra prongs block propagation so there is no benefit. Platinum plugs have real benefit in plug life and also in firing mixtures that are not ideal. If everything is good there is no significant power or economy advantage.
If your engine starts to run a little rougher or is harder to start it is often a good idea to try new plugs, regardless of the age or type. Otherwise, ignore them.

 

[MH Hawker]

Re: premium spark plugs

This sort of got me to thinking to see if their was a running hour change out on my plugs. I couldn't find it if their is. But I have made it a habit to change them out at the start of every season just because its a 2 stroke. I bought a dozen plugs a few years ago just for that reason and keep a extra set on the boat. Last year I ended up with 164 hours on a set and it was running just fine but I changed them out any way this spring. Its the standard NGK plugs.

 

[H20Rat]

Re: premium spark plugs

I've actually run dynamometer tests on race engines with different spark plugs and different wires. There are differences but they are tiny. (i.e. 0.74 hp on 300)

From the results I've seen, you can consistently gain more horsepower by indexing the plugs correctly, vs the plug selection. (outside of temperature range of course) And that being said, nobody outside of very dedicated racers actually bother to index plugs even.

 

[rallyart]

Re: premium spark plugs

Yeah, indexing is a pain as it requires careful remachining of the holes and them you're still messed up if you change brands. It can benefit the flame propagation but is a bit different for each combustion chamber shape. I always spent my effort on airflow and fuel mix.

 

[bruceb58]

Re: premium spark plugs

Indexing is such a big waste of time on a marine engine. You would get 1000% more improvement just getting the engine up to a higher temperature with closed cooling.

I used to be involved with some guys that raced motorcycles and used dynos to verify their changes. Indexing plugs did basically nothing.

 

[82rude]

Re: premium spark plugs

sorry bruce but i think i will take evinrudes advice about indexing the plugs on my etec over your advise that its a waste of time.this is of course unless your talking about inboards then i cannot say weather your right or wrong as im not familar with them atall.

 

[bruceb58]

Re: premium spark plugs

Talking about 4 stroke engines. Indexing in an Etec is necessary because of its injection nozzle so close to the plug and its direct injected. Indexing is actually necessary because you may foul the plug more with that engine if you don't.