Rep Power: 187

i went to go order new plugs cuz i think mine are still stock ones, but whats the difference between these 3?

stock heat range
1 step cooler
2 steps cooler

http://www.procivic.com/pages-produc...598/index.html

not really worried about gas mileage if one or the other will give a bit more performance over stock

 
Rep Power: 199

The heat range has NADA to do with power or gas mileage. It has to do with plug life mostly. It only has to do with power if you have one fouling out. If you have a mostly stock plug, stock heat range will do fine for you. Pull the plugs and "read" them. If the plugs show that they are burning correctly don't change a thing. Put the same thing back in there. The only reason to change them is if performance mods change it, turbo, racing; ie high rpms for extended times, MAYBE if you change to a different fuel type, ie high octane fuel etc., usually if it comes from the pump it will be fine though. If you are just driving its fine stock....

 
Rep Power: 187

ohhh okay. i was under the impression they needed changed after xx,xxx miles. but i always use premium gas anyways.
how do i know if something is wrong when i pull the old ones out?

 
Rep Power: 187

and i drive it pretty hard lol

 
Rep Power: 199

Not recommending a Haynes manual at all, but on the back of most of them there are pictures of spark plugs to "read" them. Ideally they should be clean and maybe a tad orangish type glaze on the ceramics. Look around on the net for images, sure they are out there....

 
Rep Power: 811

stick with the stock heat range denso iridium.