1. Low fuel consumption
2. Excellent acceleration and performance
3. Stable combustion during idling
4. Long life and high reliability
5. Features iridium with high melting point

Editorial Review :

Denso Iridium Spark Plugs are designed to ignite the air-fuel mixture in the engine cylinder by generating sparks between the center electrode and earth electrode. They employ an iridium alloy for the center electrodes and provide superb ignition performance. These plugs have lower fuel consumption and higher acceleration performance as well as stable combustion during idling, which contribute to the cleaner exhaust.

Customer Review :

Fit my car

Was shipped promptly and arrived quickly. It was well packaged than a previous set of spark plugs I bought from Amazon. Amazon must be reviewing these reviews because I complained about the packaging the last time. Anyway, it is good to have a responsive seller who cares about what customers say.
I haven't observed an improvement in my gas mileage but I haven't been paying attention to it.

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smooth running engine with this Iridium spark plug

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.

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Working Great!

Bought these as part of a full tune up to my wife's '03 Honda Accord EX 2.4L. Engine is running smooth and strong...these did the trick. Hopefully, we'll see some mpg pickup like the previous reviewer as well! Only had them in for a week.

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Faster Starts

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.

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Excellent

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.

Rating :

1. Patented fused iridium and platinum center electrode, sintered into an extended insulator nose, provides exceptional wear resistance and reaches
2. Revolutionary surface air gap firing technology featuring Bosch's unique four ground electrode design, delivers the most powerful spark for the most efficient combustion and optimum horsepower without increasing the voltage requirement
3. Four yttrium-enhanced ground electrodes resist spark plug wear and oxidation for exceptional performance life
4. Factory pre-set gap set to provide ease of installation - never requires adjustment
5. Contains one spark plug

Editorial Review :

Bosch Platinum IR Fusion spark plug has an iridium and platinum fused center electrode with surface air-gap firing delivering optimum horsepower, better than OE iridium plugs.

Customer Review :

Perfect Plugs in my Impreza

These have been running strong now for 30,000 miles. They start the car 1-crank faster and have not given me any trouble. Fuel economy is what it should be as well.

I will purchase these again when they are worn. Finally, a good spark plug from Bosch!

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victor

I ordered Bosch 4501 Platinum IR Fusion Spark Plugs through Amazon and everything went perfect. They were delivered on time I installed them on my Mercedes and it made a great difference in the performance of the car. The price was great I recommend Amazon Bosch 4501 Platinum IR Fusion Spark Plug , Pack of 2 to anyone they're superve and you will notice the difference immediately.

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Bosch has arrived with the 4501

3days and 350 miles on these and the VR6 Jetta has new life.Runing strong, full o pep.Code 411 has not returned after clearing code with new plugs. Have not studied mileage yet, but looking to increase for sure.
Expensive yes, but great peace of mind in having these.

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Good Plug - However, No Noticeable Fuel Mileage Increase

I have two Toyota Camrys. A 2004 SE and 2006 LE. Both have the same 4 cylinder engine. I have always been religious about checking the gas mileage on my cars at every fill up because this relays to me if anything has gone awry. The '04 had 115,000 miles and the '06 had 45,000 when I replaced the plugs. I replaced them mainly to see if it would help the fuel mileage; unfortunately for me, no difference. I'm sure they are good plugs as Bosch is well known for their high quality, however next time I will probably replace using the factory spark plugs.

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more MPG

i placed this spark plug in my 2002 misubishi lancer and increased its MPG from 29.5-34 MPG and thats about 4.5 MPG increased. highly recommended product.

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More reviews...

1. 8.50mm in diameter
2. Red wires with grey boots
3. Spark plug boot material is silicone
4. Helically wound core has only 40-50 ohms resistance
5. Dual crimp stainless steel terminals

Editorial Review :

A tough 8.5mm synthetic/silicone jacket over an extra-heavy glass braid and dielectric insulator keeps the current guided to the plugs. The MSD super conductor wire set has dual crimped stainless steel terminals. A helically wound core has only 40-50 ohms of resistance per foot. MSD Ignition warrants its products to be free from defects in material and workmanship under normal use, if properly installed, for a period of one year from the date of purchase.

Customer Review :

Great performance upgrade!

These MSD wires give my LS1 performance. After 60k these wires with new spark plugs make the motor run like new. Strong.

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MSD- Hot Wires

Installed these on my C5 Corvette, Much better wire than the stock factory wires. Exact fit.

Rating :

1. Patented fused iridium and platinum center electrode, sintered into an extended insulator nose, provides exceptional wear resistance and reaches
2. Revolutionary surface air gap firing technology featuring Bosch's unique four ground electrode design, delivers the most powerful spark for the most efficient combustion and optimum horsepower without increasing the voltage requirement
3. Four yttrium-enhanced ground electrodes resist spark plug wear and oxidation for exceptional performance life
4. Factory pre-set gap set to provide ease of installation - never requires adjustment
5. Contains one spark plug

Editorial Review :

Bosch Platinum IR Fusion spark plug has an iridium and platinum fused center electrode with surface air-gap firing delivering optimum horsepower, better than OE iridium plugs.

Customer Review :

Good Plug

These plugs seem to work well. I don't know if there is an hp or mpg gain but my engine is running quieter. The Bosch website make these seem like the best plugs ever. I hope so.

Rating :

Not bad ...BUT...

Well I finally changed my old plugs with these ones, got more power engine, better gas mileage BUT i notice my car starts vibrating as soon as I hit 60 mph. dont understand why but that is my only issue.

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Spark Plug

I have my husband put on this Bosch 4505 on my explorer (SUV) and the SUV runs excellent...

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Worth the money

Hey, these things really make my LS1 run a whole lot better.
By better, I mean better mileage and smoother performance.
I just bought them because I had 30K on the old ones. I was
surprised to feel a power difference.

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Fits my 99 Ford Taurus fine

In conjunction with new Motorcraft plug wires i picked up a few horses and i think a tad better mileage so far. Have driven over 500 miles on them no engine codes or problems so they run fine. Went into my 99 Taurus with a Vulcan engine

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1. NGK # 5464
2. Constructed from durable material
3. Fine Iridium tip ensures high durability
4. Features superior anti-corrosion and anti-seizing properties
5. Iridium alloy has extremely high melting point, perfect for today¿s high-tech, high-performance engines

Editorial Review :

NGK Iridium IX Spark Plug is designed to offer extreme ignitability, improved throttle response and superior anti fouling capacity. It is constructed from durable material that is corrosion and abrasion resistant. This Spark plug features a fine iridium tip that ensures high durability. It ensures longevity and can easily be installed.

Customer Review :

Great product

Definately the best spark plugs I have ever used. Replaced old bosch platinum plugs in my maxima, and I could definately feel the difference.

Rating :

Great plugs!

This is my second time buying from the Iridium-IX product line for my vehicles. Bought these plugs with the wider .044 gap (code BKR5EIX-11) for my 2006 Scion xB. The larger gap is said to allow for a better spark and improved gas mileage. (As I understand it, timing is retarded slightly to account for lag created by the larger gap.)

Anyway, here is what I have seen so far:

-Idle is now super smooth. Before, the idle would hover near 900rpm and then suddenly drop, then back up again. These allowed for a solid idle that stays around 1k rpm with no dips. The (stock) plugs I replaced had less than 12,000 miles on them, and did not show signs of abnormal wear or other issues...so I don't think they were specifically bad, just not as good as the new iridium plugs.

-Acceleration "feels" stronger and smoother. (no dyno testing or anything....just how it feels to me)

-Mileage has increased. I am getting about 2-2.5 MPG more with these plugs....that's about an 8% increase.....not too bad in my opinion.

Also, being iridium, these "should" allow for a longer service interval before they need to be swapped out again. (Though I will likely not let them go anywhere near the 100k that they can reportedly go....especially since I went with the larger gap to begin with.)


Rating :

World's Finest Spark Plug!

I have four of these plugs in my 2002 Corolla with stock ignition and they are Fantastic! I just checked them after 11,636 miles and there is no electrode erosion on these plugs (Checked plugs with a wire gap tool)! I would suggest to everybody who changes their own spark plugs to at least check them around every 12,000 miles or once a year (even if they are long life plugs, reading the plug will let you know about any potential issues with the engine). If your looking to put better plugs in your Corolla, NGK Iridium IX is an excellent choice. Fuel economy on the Corolla does slightly increase ~1% but every little bit counts! Another pointer is to drive conservatively and (if you can) anticipate traffic flow, curves, hills and don't ride the brakes - increase your following distance and let the car coast down the road. God Bless and happy trails!

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Honda Idle

My Honda Foreman 500 used to be very cold natured until I put this plug in. It now doesn't need to be started by choking much of the time and when I do have to choke the engine, it can be unchoked after starting where I used to run with choke for a while before it would stay running. Great plug.

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Great Plugs, Well Worth It

Have used cheaper plugs in my 2002 Ford Escort (Autolite, etc.), you can notice a difference in engine performance (although that's a highly subjective statement).

Only other plugs I currently recommend are the bosch.

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