what plug is better for performance? platinum or copper?

 

Copper. Can't go wrong with NGK for quality and price.
TR5, TR55, TR6 all work well.

 

Does the TR5, TR55, TR6 signify the heat ranges or what?

 

Also I'm looking for a little more performance than what I have now and I am trying to utilize the gain with what I have. Does anyone have any suggestions? Thanks again for any info.

 

The best two performing plugs that I have run in my truck is denso iridium & acdelco/denso platinum. I would be running the acdelco/denso platinum (#41-974) in my truck but they are too hot of plug for my application so I am running the denso iridium it20 which are colder than stock. Both of the plugs gave my truck more pep. I have ran acdelco platinum 41-952 & 932, ngk tr55 & tr6's, and also the bosche +4's. The bosche +4's ran the next best. The only down side to the denso iridium plugs is they costed $11 a pop were as the acdelco/denso jap plug & bosche +4 plug cost $6 a pop.

 

NGK has iridiums now for $5 a plug. TR55ix, Orielly's sells them. I could tell the differance after installing them. good plug.