My engine is stock, I thought they sold them the same heat range.

 

I ran Bosch platinum +4's for two years street and strip (12.70's) and had no problems and they looked just fine when we took the motor apart to build the stroker.As for ngk Iridiums the benenfits as stated in their catalog is that the ignitabilaty and durability are better then platinum.That being said I doubt their worth the extra price. When it comes to plugs it is about the heat range. All plugs are pretty much equal. If the motor is tuned properly all should work just fine.Everyone has a personal preference and with a moded motor you have to find the proper heat range. I am currenty running NGK racing plugs that the engine builder recomended for my set up.

 

I now run the NGK Irridium plug.
Did not notice any performance gain, it did seem to idle a little smoother though. The reason I installed them is their long life.
I do not want to have to replace them as often bottom line!!!
I now have about 35,000 miles on them with no problems.
Same performance without replacing as often is fine with me!

Michael

 

I agree that there may not be a performance gain, i am more concerned with durability. If i can find a plug that will last longer for the money i will try it - that's my main concern here. My concern with platinum plugs is that the 'coating' of platinum lasts a very short time - i'm hoping to find out the iridium lasts longer.

 

I agree that iridiums are way to expencive. the only advantage to the bosch platinum 4s are that since their are 4 electrodes when one of them becomes out of gap the spark will follow the path of least resistance. I put the split fire tripple platinum in my car and they are great.

 

What does the 'triple platinum' mean? Are they triple coated to last longer? How much were they?

Sorry for all the questions - i need to make my decision soon.

 

if you ever look at a split fire plug, it has one electrode that splits at the end so there are two spark pulses. and all three ends are platinum.

 

I did notice a much smoother idle with my NGK Iridium IX plugs. I say they are worth every penny. It drove like a new car.

Iridium plugs are also supposed to last far beyond 100,000 miles. Apparently Iridium is one of the hardest natural substances, and will almost never wear down. I know people who actually remove and *CLEAN* their NGK Iridiums instead of replacing them.

 

How do they clean them? What do they use?

 

What heat range or part number NGK iridium are you guys using.
I was told mine NGK Iridium plugs are too cold by a guy who has them on his TT 69 Camaro. He has the same plugs on his car.