Customer Reviews

Denso (5304) IK20 Iridium Spark Plug, Pack of 1

5 star:		(23)
4 star:		(4)
3 star:		(0)
2 star:		(1)
1 star:		(4)

 

 

Picked up a set of these to replace the stock NKGs on my 2005 Honda Accord 4 cylinder after 97k miles. The originals were still good -- just doing a spring-time overhaul.

Engine felt smoother although that could be psychological. What is real, however, is a solid and consistent 2 MPG increase in fuel economy from what I was averaging over the last 60k miles.

I'll try to update this review after 30k miles or so.

This fits in 1999-2003 Toyota Sienna. Trick to replace the three spark plugs in the back is to remove the windsheld wipers and the plastic piece for intake air and rain water collector -- a big piece from left to right.

After the spark plugs replaced, the engine runs smooth, starts faster. Since Iridium is very expensive, the tip is little -- 0.4mm in size, so that it can spark easily. Denso's web site says it has life 60,000 miles. Denso also developed one for Toyota and Lexus that has 0.7mm tip, that one can last 120,000 miles. 0.4mm has more precise ignition time, so that better fuel econemy.

Until recently, platinum was considered the best material to use on the top of an electrode because of its durability. However, Iridium is 6 times harder, 8 times stronger, and has a melting point 1200 degrees higher than platinum. Put that into a harsh environment such as an engine piston chamber, and you have a spark plug that can resist wear much better than platinum.

I just installed a set of these in my 2001 GL1800. I previously had NGK standard plugs with under 1,000 miles on them and AC Rapidfire plugs with 24,000 miles on them.

The AC Rapidfire plugs were my previous favorite, but it seems they are not the same plug anymore, having lost the serrated center electrode. The Rapidfires I had previously installed were the non-serrated type. They still provided faster starts than new NGK plugs, but not the improvement I had witnessed in other engines with the serrated Rapidfires.

The IK20s, which, in spite of the title and picture, are Iridium Power plugs, provided about a 1/2 second start time, where new NGKs gave a slightly longer than one second start, and the Rapidfires gave a slightly less than one second start. The engine is running smoother than with the 24,000 mile Rapidfires, but that is no suprise. I can't tell if it is running smoother than with new Rapidfires, as the difference is negligable. That is the extent of my review so far, as I have not yet collected enough data to see if I get a fuel economy change, and the power difference is too negligable for me to tell.

The Iridium Power spark plug is good for 30,000 miles as per the Denso FAQ. If a 5% fuel economy gain is achieved, then the plugs will pay for themselves a couple of times in that time.

There is also a Denso Iridium Tough plug available, the VK20, which is supposed to give less of the benefits of the Iridium power, but last 60,000 miles while still giving improvements over conventional plugs.

I have been using iridium since 2001 on my civic. I saw quite a few comment about lifespan of the plug.
My denso iridum on the box said good for 250000 miles, and my civic is at 260000 and still running swell.
So they do last long, unless they reduce the quality so denso can make more $$.

I have tons of pictures above!

Denso IK20 = Electrode .4mm (rated 30k)high performance, low mileage
NGK BKR6EIX-11 = Electrode .6mm (rated 60k-70k) mid, mid
NGK IFR6T11 OE = Electrode .7mm (rated 120k) stock performance, high mileage
Denso SK20R11 (OEM long life)= Electrode .7mm (rated 120k) stock performance, high mileage

Hope this helps. These are 4 top-rated plugs. Rated mileage varies on these plugs depending on various factors of your engine. Keep your engine fuel clean and u should be fine. Toyota recommends the SK20R11 but I found in the owners manual that the discontinued "IFR6A11" is also comparable replacement, the new one is the IFR6T11.

I've tried SK20R11 and it lasted about 110k but there was some compression leak (plugs were still good though). All of these are excellent plugs. I have not tried IK20s yet but will purchase some though the 30K life is pretty short. I hate the 1mz-fe engines with the 3 rear plugs which are a *bleep* to change. Anyone have tried all three or either of them should give us some insights.

According to a previous review, if the IK20 gives a 1%-5% increase in fuel efficiency then you should opt for the IK20s because it pays for itself within a few thousand miles provided you have the time to change them out without too much inconvenience. I don't buy into the MPG hype but i'll try it out since I have the IK20s already.

Denso (5304) IK20 Iridium Spark Plug, Pack of 1
NGK (3764) BKR6EIX-11 Iridium IX Spark Plug, Pack of 1

Opened up the boxes. Checked the gaps (all were perfect). Put some anti-seize on the threads. Installed the spark plugs with no problems. Car is running well.

I replaced the factory installed spark plugs on my 2003 Camry with these ones after reaching 90k miles. There was nothing wrong with the old plugs but I read on lot of websites that it is a good idea these kind of spark plugs after 90k miles and I am a believer in preventive maintenance. Installed these new ones in 30 minutes and it's been a week and no issues so far. I am not seeing any noticeable improvement in gas mileage or anything else but that was not my primary goal.

First off, my hat comes off to amazon for really doing a great job getting such a wide variety of items. Now the Denso (5304) IK20 Iridium Spark Plug is great for the price. Really gets the job done. Plus these plugs lower fuel consumption and while enhancing acceleration performance. You notice it immediately, They boast cleaner exhaust which is great but I cant actually tell.

After reading reviews, talking to mechanics and taking auto manufacturers relationships with suppliers as sceptic, I tried these plugs in my Mini Cooper 2003 (a hesitant slug) which was seen by the reputable dealer with this complaint. Never improved after their expensive tuneups. With near recommended gap (all 4 matched) , the hesitation is gone. Normal heat range, these inspire you to drive more sportingly with somewhat greater efficiency, yet the real gain is in sureness entering highways. The previous factory recommended plugs do not come close. They (set up correctly still hesitated) Makes you wonder? I put 5 in my wife"s Volvo V70 with similar yet less dramatic improvement. Is this rather subtle company one of those best kept secrets?

Have a Honda Civic with 70,000 miles on it and noticed lately it seemed to be running rougher and gas mileage had slipped and even though spark plug change on the Civic isn't suppose to be until 110,000 miles I decided to give a new set of plugs a try. The standard plugs for the Civic are Denso so decided to stay with Denso. After some research on-line I went with the Denso IK20 plugs. Amazon's price was a lot less then I could have purchased locally even with shipping. Plug changing on a Civic is super easy and the results were what I hope for, smoother running, more zip, and better gas mileage.