Hey All,

I have a 2000 Mazda Protege, with the 1.8L engine. The car was purchased for pretty cheap. I'm doing some basic mantenance items for it. Curious about what kind of Spark Plug is the best kind of spark plug to put in the car?

I've been told by a few friends that are "motorheads" to use a platinum spark plug. Others have told me to use iridium.

Can someone please provide a little insight on this?

Also, I am curious if any suggestions on plug wires can be provided.

Thanks!,

 

I have Denso iridium plugs and they are great. I believe they give a slightly hotter spark than platinum.

COPIED: through recent technological advances, DENSO has harnessed the power of Iridium. DENSO?s patented alloy is composed of iridium, complimented by rhodium (an even stronger metal). The rhodium is added to increase oxidation and wear resistance.
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. Additionally, the DENSO Iridium Power alloy is so durable; it allowed our engineers to produce the world?s smallest center electrode (.4mm) which reduces the voltage requirements, concentrating its sparking power. Also, its smaller size, combined with the tapered U-Groove ground electrode, allows more room for the flame kernel to develop and produce a more efficient combustion.
For example, many newer Lexus? and Toyota models carry an ultra long-life Iridium plug variation (.7mm with platinum tipped ground) that is capable of up to 120,000 miles of service. DENSO Iridium Power plugs, with their .4mm center electrode, have been developed for performance applications. Because gradual wear will ?round-off? firing points over time, the concentrated firing power and voltage requirement benefits will be reduced. For this reason, DENSO advises replacement after 30,000 miles.
ABOVE FROM: Frequently Asked Questions: DENSO Iridium

So, platinum- and iridium-coated plugs with a copper core won't boost horsepower or fuel economy; they'll just last longer and perform more consistently. Performance fine-wire plugs can enhance efficiency by helping the flame front to initiate and spread a bit more quickly, which potentially means more fuel burned per compression event and less fuel wasted. Both platinum and iridium fine-wire plugs will outperform copper-tipped plugs, but the iridium's ability to withstand high temperatures allows for a thinner plug tip. In the real world, though, you're unlikely to see any measurable change in fuel economy using iridium instead of platinum plugs. Platinum will do everything iridium does outside of the most severe racing applications. Iridium can give engine builders a slight edge in very high-compression, turbocharged or supercharged engines, but this edge isn't likely to translate into increased fuel economy in a street engine.

Read more: Platinum Vs. Iridium Spark Plugs and Gas Mileage | eHow.com Platinum Vs. Iridium Spark Plugs and Gas Mileage | eHow.com

 

Or if your like me you just put in the OEM recommended plugs and run with that, wont run any worse than stock that way. OR if your on a very tight budget like I have been lately you get the cheapest ones available, throw them in and just keep taking them out every 5-10K and regap them Also like Noggin said your fuel economy gain might be so slight that the cost of the plugs outweigh the "savings" in fuel.

The one big downside to everyone getting the platinum or iridium plugs is they put them in (without anti-seize no less) and forget about them since they are "good" for 100k sometimes, you still HAVE to remove the plugs from time to time (25k-50k miles) or they can, and usually do, seize in the heads. When this happens the next person to try and remove the plugs will either rip the threads out of the head or break the plug in the head and its still stuck there (been there done that, not fun).

 

This is true. This video explains this exact situation:

Goss' Garage: Spark Plug Removal - YouTube

WOW what a difference! The actual video is displayed! This is a great improvement.

 

And one more thing: stay away from the gimmicky E3, pulstar and such. That's money thrown out the window.

Copper yields the strongest spark, but lasts for a very short time only. That is why the manufacturers turned to platinum and iridium.

 

For a simple 1.8 use the standard listed plug. You will most likely not notice or feel any difference running the fancier & more expensive platinum or iridium plugs.

I recommend NGK Spark plugs.

At a guess, & DO CHECK A PART CATALOGUE, you will probably need BKR5E-11.

 

Hey All, Thanks for the information above.

I ended up getting the Bosch Ir Fusion Platinum plugs. Main reason, these plugs do not require gapping.

The change went over pretty simple, I have yet to do the wires. I think that's a project for this weekend, when I do the oil/filter change, ignition coil pack replacement.

I was going to go with NGK plugs & wires per the suggestion of a friend and coworker, and also of this forum. But, the only set according to Napa was there was only one set in the entire US in their system.

I do have a question though. Should there be oil on the plugs? I know to use anti-seize on the plug itself. But when I pull out the old plug, should their be oil on it?

Thanks!,

Dan
(Windbk)

 

Oil on the porcelain? This means the rocker cover gasket is leaking.

 

Well, I'm not entirely sure. I've been trying to upload a picture of the plugs. But the site isn't letting me for some reason...

Here's the photobucket link.
IMG_20130112_210554_zps9c211111.jpg photo by dsmith225 | Photobucket

The old autolite plug is on the top in the socket, and the replacement bosch plug is on the bottom.

Say, if the rocker cover gasket is leaking like you suggested, @grim_reaper. Is it hard to replace?

Forgive me for many of my questions that I ask, for I'm rather new at working on cars. Much more comfortable tearing a computer down myself and rebuilding it better.

Thanks!,

Dan
(Windbk)

 

Oil on threads means it came out easy. Tip looks good. Sounds like leak from above.
Currently I have NGK iridium # TR5IX, # 7397, .6mm tip with Accel hi output voltage coils.
NGK is recommended for Mazdas.