NGK Iridium Spark Plugs - Any comments?
 

Does anyone have any experience with NGK Iridium spark plugs?

Someone asked about them last week. Too me they are overpriced. Why not just stick with plain old NGKs?

I'm curious if anyone has experience with Bosch Platinum +4's in a 911. They have a 4 pronged tip on the plug and the box says you never need to gap them out of the box...

Trying them in my rice car, so far so good.

Bosch Platinum anything basically get a bad rap in these parts. Stay away. The spark always goes from one electrode to another - never from 1 to all 4. There's no advantage. It's just psychological.

The NGK Copper plugs have never let me down.

I have them in my turbo saab, and they have by far outlasted any copper plug for that car. But they are way to expensive for non turbo's. Do they make my car run better? Nope! Just last longer.

I run denso iridiums in my supercharged toyota solara and they perform very well. I went with them because I needed to go one step colder, they were well tested at my level of boost and application, and they were easy to find.

Have you ever heard of Unobtainium? If you replace clapped out plugs with any new plugs the car will run better.

Fouled Bosch +4 plug
 

I have tried Bosch +4 plugs with similiar poor results on two cars. Both are Volvo 240s. One is 30 years old and the other is 20 years old. In both case 1 of 4 plugs fouled. the O2 system "saw" the unburnt fuel as a rich running car and leaned down the mixture. So, 3 plugs were running lean and therefore a bit hot.

I use them in my 73S with MFI. I believe that the car does start up a little better, especially with a rich idle mixture.

Good plugs, very pricey. A better NGK to use would be the NGK BP6ET (3.2 engine). They will last longer than the copper plugs. Durability is excellent. You will have no regrets.

In my experince depended on a particular engine. Like a
3.0 or 4G63 or 4AG, M52, etc and then it trickled into say if modifications or tuning was carried out.

You also have to becareful about gaping. It is possible in particular engines to gap and basicly have piston to plug contact. It depends on application.

My experience with NGK Iridium : on a 911 3.2 /1986 model , that runs fine : i heard a noise a bit like a "click-click" , i checked springs valves , rockers arms ...............always tor Boschhis noise.

Just for trying , i changed my NGK for Bosch spark plugs.............and the "click-click" has dissapeared.

Try to test the Ohms resistance of a NGK ; you'll see that every sparkplug has a different value , that i can't explain.

All that i'm sure is that the taping noise is solved.

Until you go to gap them and break off the tip.:( Back to the cheapo plugs for me.

Use what is recommended...the expensive plugs are just expensive snake oil.....

Luv'em
 

I have used them on everything from 3.2 L Carreras to John Deere 335 lawn tractor to Audi A8 and even mfi 911's. I bet they would also work well in carbed 911's where the plugs have an issue with carboning up. They last forever, hold their gap well and start ups are fast...which helps on the starter. They are not even close to expensive compared to Denso's.

I use them in my supercharged Miata, and they are recommended for bosted applications with water or methanol injection.

I use the Bosch copper in my Porsches, because they are from the same era, and work well with Bosch Fuel Injection of that era.

The NGK is also a good plug. Bosch Platinums can fluff in a 911.

You don't need to gap them. Just look and insure the ends are not damaged in the packaging. NGK factory settings are better than I could do on the bench. They do great right out of the box. Try them, no issues.

You do when you are running over 23 lbs of boost and it blows open the gap after a while, different car though.

Have never had a better plug than the BERU quad plats that are currently in the car. Who's recomending Jap plugs in a Porsche to you guys anyway?? whats next a cheap set of champions? Ha! Ha! Just kidding guys! ALWAYS USE WHAT YOUR COMFORTABLE WITH AND UNDERSTAND!!