[KenCrawleySC]

It took 1.5 hours to do the job. That including "admiration" pauses.
The plugs were sooty on the threads and the insulator was tan with some soot. Unless something changes, I am going to go to the hotter plugs next change. I also waited way past the 16,000 mile plug change interval. It was unnecessary at that time, and I feel that, with the improved running I noticed today after doing the plugs, perhaps the best time would be around 20,000 miles.
Ken 24,300 miles

 

[phat6]

Spark Plug Replacement - 24,358 Miles

I agree with Ken, 24k is too long between plug changes, especially the way I ride. Plugs had some nice carbon coating on them (dry). This might have been somewhat a result of the BBS I had, but the dealer assured me at that point the plugs looked fine and did not need replacement. I searched the cross-references and some bastardized cross-referencing (the plug that fits the Rune, also fits car xyz, so see what else is out there for car xyz, and make sure it is very similar). Some cross-references seemed to be one direction only, i.e. this plug works in car X and car Y, but car X and car Y show different plugs. I ended up putting in the Bosch Platinum Ir Fusion, Bosch PN 4501, $10 a cylinder, yikes! Physical size is comparable, including electrode protrusion, etc, so no fit problems; these fit perfectly. The gap is not adjustable, and is .01" bigger than recommended. We'll see what effect this has if any (doubt it will have any impact). There are a number of Acuras that use this plug, and this crossed to the NGK model in the owners manual for sustained high speed riding, who would do such a thing 8) . These are fused Iridium/Platinum plugs with 4 electrodes and a straight exposed spark kernel. I will test these out this next week and post mileage, etc. to see if I notice any change from when the Rune was new.

 

[KenCrawleySC]

Well, 2.5 years later, and at 45,150 miles, I guess it is time to change my plugs.

Phat: you did not post your results of spending all those simoleons on Bosch plugs. Is it worth it?

ken
(45,150 Rune miles - Oct 8 2007)

 

[WIZ]

put the stock NGK plugs back in it.........sold at any auto parts house....
$1.98.......changed mine before myrtle beach [email protected],000 miles..
took 30 mins........max ...........and thats putting it on the lift....
changed the oil @same time........and the final gear oil.....over $400.00 if dealer would of done the job........cost me alot less........ :lol:

my plugs looked exactly as you both described and could tell a difference
of a more smooth idle.......i would not wait past 15,000 miles personally......

 

[WIZ]

Ken,

I wonder about all that extra heat from the increased spark on the top of the
piston? Increased wear? Increasing air flow like I did with the airbox mod
could do the same thing.

Tara

not a concern.........a piston is not pin pointed in any area......
when a spark plug fires it ignites the fuel/o2 mixture in the cylinder....
the heat of the explosion is absorbed by the full top of the piston and
cylinder walls......you can not melt the top of a piston with the spark
it creates .....only the fuel/o2 mixture that it ignites...... i hotter spark plug
would only keep the electrode cleaner longer......thus live longer.....
or in theory.........unless you have an intake and exhaust spark plug...
it would be hard to see or fill any benefit..........

 

[phat6]

Well, 2.5 years later, and at 45,150 miles, I guess it is time to change my plugs.

Phat: you did not post your results of spending all those simoleons on Bosch plugs. Is it worth it?

ken
(45,150 Rune miles - Oct 8 2007)

Sorry, buddy, never did get back to this thread until now! Posted the answer in a different thread:

"Researched back and forth across the web for hours to find what looked to be a very close match for plugs, but the performance type plugs I wanted in the high temp / "sustained high speed riding" version. Found the Bosch Platinum Ir Fusion Plugs, 4501. These work great. I get slightly better mpg that I ever did on the previous plugs (0.5-1.0 mpg) and about 3-4 mpg better than what I was getting before I replaced the plugs. The original plugs I pulled were carboned over. I tend to do a lot of riding > 100 mph, so the high temp version was the obvious choice for me. Hoping the variety of plugs I chose will last a long time as replacement every 15-20k is a little annoying."

http://www.runeriders.com/forum/showthread.php?t=3784

BBS may have contributed to the short life of the original plugs. With all the mods I have made on my Rune, I typically get 38-40 mpg running ~80 mph now. It is about time to check the condition of those plugs to see if these hold up longer than stock, but I am still getting 38-40, and occasionally 41, so I expect these are still in great shape. I am probably not even going to look until I see the mileage start to drop slightly! These seem to last longer than stock as one would expect with this type of plug, so to me it is worth it just to not have to screw with it. The better mileage is an added bonus!

BTW - the "sustained high speed" version is actually a lower temp plug as someone correctly pointed out.