which plug should i use and a quick write up would be nice.
torque specs needed?
correct gap measurment?

 

Yes what are the stock sparkplugs used with the evo?

 

stock are iridium but i'd rather not spend that much on plugs

 

Ngk Iridium

 

if you skimp out on anything for your car itll get you back. kind of like taking a first date to mcdonalds.

 

why would RRE use NGK Copper?

 

Check this out... a little over a month ago, I did this whole writeup because another member was caught between denso and ngk... here are the difference...

OEM - NGK IGR7A-G
DENSO - IW22
NGK - BPR7EIX (do a search, can't remember the whole part number off the top of my head)

Anyway, those are 3 of the more common ones... It's established that OEM is one of the more expensive ones... reason being the center electrode is iridium and the ground electrode is platinum tipped.

next in line would be the denso... it has a center electrode width of 0.4mm... reason being is less resistance, to provide a better spark with the given gap and to reduce quenching...

right behind that would be the ngk iridium IX... the center electrode is slightly bigger at 0.6mm... also a good sparkplug and a bit more affordable price than the denso plugs and oem plugs... the other reason why rre would use copper plugs is because they're cheaper, gappable (most plugs come pre-gapped anyway) and give you similar if not the same performance. downside to that is that you would have to change them out more frequently than the iridium plugs...


torque specs for the spark plugs are 18 ft-lb plus/minus 4

biggest PITA is getting the coil pack off the spark plug... Just keep pulling even though it feels like you might break something... they're on there 'that good.' once you get the hang of it, it's cake work... don't for get spark plug anti-seize...

 

using ngk coppers is not skimping out necessarily... look at it this way... it's like comparing something name brand to something that's not... they both do the same thing. just don't expect the non name brand to last as long as the name brand item even though they are made from the same manufacturer...

Oh yeah, btw sometime this coming year the OEM plugs will become available in autoparts store... they've already dropped in price... you can get them from www.sparkplug.com ... cheapest place i've seen so far...

 

I just put some Denso iridiums (IW22) in my EVO on Saturday. I'm not sure if it was real, or a placebo effect, but I swear the idle is smoother now. There just seems to be less vibration through the steering wheel. When sitting in the driveway.

I also had my OEM plugs completely foul out on my one very cold day last winter. It took HOURS to get the stupid thing started, eventually requiring me to pull the plugs and heat them up with a propane torch!

There was an article a couple years back where a magazine dyno-tested several major brands of plugs and compared them on various engine types. There was one pushrod motor, one high revving VTEC 4-banger, one turbo 6 (a Skyline GT-R), and something else (a truck?). They found the most HP gain on the Skyline using the Denso plugs. I think it was 5+HP! Then again, back then I don't think NGK had an iridium plug yet, so I'm not sure how they compare. I work for Denso, so I'm definitely biased.

 

Hmmm... how much do you get yours for? I'm not biased, but I'm all about getting a good deal... I have the ngk iridium ix right now...