93zder

I will be getting my plugs changed in the spring and am unsure whether to stick with the AC Delco Platinums or TR-55's which i have heard a few people use. My car is only lightly modded with maybe headers and a cut-out in the near future. What is working best for you guys?

I've heard that unless they are platinum, they require more spark to work - therefore make less power. Is this true?

Gripenfelter

I use NGK TR55s.

hairbear21

Bosch Platinum +4's - be VERY careful to not hit or bump the ground electrodes, there is not way to set the gap.

93ZM6Tally

AC Delco Platinums - seem to work fine

user guest 45

ngk tr55IX

95TA8280

Bosch +2s.......

allmotorta

NGKTR55's

UkraineTrain350

any plug with more than one ground electrode is merely a gimmick and therefore a waste of money, especially bosch +4s. there is also a big myth about platinum increasing power, it absolutely does not. its purpose is to reduce wear and that's it. the best plugs to use are finewire platinum, the platinum makes the plugs last a long time and the finewire refers to the center electrode being very skinny (~.8mm) which reduce the voltage required to create a spark.

z28Power

Man, this is posted all the time. I would do a SEARCH and you'll probably find a multitude of threads on this, as I have seen quite a few in the past 2 weeks alone.

hairbear21

Ukraine, do you know how +4's are designed to work? True, platinum will not increase power, but there is no deteriation in the center electrode, that is why they last longer. I explained this once before, and the multiple electrode design is centered around efficiency not power. Power if any, is merely a biproduct of the efficiency. The way that they work is, when one of the ground electrodes' becomes hot (and it will), another one becomes the focus of the spark. Think of it as a resistor, and when a resistor gets hot, it is less efficient therefore, by providing multiple paths of resistance, the spark will always travel to the one that offers the least amount. When I put them in my car, I did not notice an increase in power (if any), but, the idle was smoother, especially at high temps, gas mileage went up (biproduct), and acceleration was up also. Granted, any tuneup will do this, but only time will tell if these plugs will do this in the long haul

aircop40

ditto!

WheelmanZ28

NGK TR55 here as well.