i have a 97 240sx and am getting ready to get it tuned i just need some spark plugs, i dont know what i need but i know i need to go a step colder, can anybody give me the part number and where to get it. are Iridium plugs the best? thanks

 

so if anybody knows anything........ i found some stuff online but i have yet to buy any of the plugs. bkr5e is the stock plug i belive bkr6e is the stock plug in a sr20det so i was wondering should i run the 6 or go colder and get the 7.

 

Just to be nice you need to ask questions with correct defenitions. The term colder plug means nothing. If you were to say what plugs withstand heat tolerance better than I could help you.
In any case I know more people that own Chevy's, Ford's, Toyota's, Nissan's, and Honda's that use the (NGK Iridium) brand of spark plugs. They are the most reliable for the price and are probably what you are looking for at $7.00 a plug. Denso is also an excellent brand but they are a bit more expensive.

 

ngk bkr7e-11 is probably the most common for a ka-t set up

 

The iridium Ngk part number is BKR7EIX-11 . The stock number you want to give you local parts store for the ngk is 6988.

And for the record, You are correct in your terminology. It is a one step colder plug. It is a colder plug. Any performance shop or parts store would know exactly what you mean. Ask technical questions if you want technical answers.