my evo 8 is lightly modded(340hp nothing special)
it has a spoolin up cop but dont know what spark plugs the previous owner used and cant get the COP off cause its soo ****in tight on that i have to drill it out
its running 1.2-1.3 bar boost

 

Stock specification plugs is what most of us use in our 4G63's

 

one says NGK's the other say denso(MD343244 Denso P22PR8)
so which is it?

 

Well, i know the spec for my EvO 9 = NGK ILFR7H

Not sure what the 8 runs off hand. I'll leave that to you to figure out Sir

There are scores of threads on this same topic

 

Stock heat range:
NGK – BPR7EIX
Denso – IW22

1/2 step colder:
NGK – BR7EIX

1 step colder:
NGK – BPR8EIX
Denso – IW24

1 1/2 step colder:
NGK – BR8EIX

 

evo 8... just use the ngk coppers.

 

Yup. Just take off the IX at the end of the plugs in my list above and replace with an S

Example: BPR7EIX = BPR7ES

 

Stock plugs are 6's I believe.

My tuner said coppers for 8s and iridium for 9s

colder the plug heat range the more power you make.

 

Stock heat range is 7

 

Stock heat range is 7.

The correct plug makes the most power. Arbitrarily going colder helps nothing. Stock heat range is good to around 7-750whp in these cars.

 

DSM EVO dyslexia

 

i like that!
wonder if they make 0 heat range plugs.
gonna get me some

 

I read a lot on here and also my tuner recommended denso IKH24 for a 100hp up on stock build. Like letsget says it probably doesnt matter going colder at low hp

 

I run stock heat range plugs at 650whp with higher than stock compression and E85, but it's an Evo 10, so not a "real evo".