Ok, I know this may have been beaten to death. But i gotta get it right. I have meth running stock turbo evo 8 pushing around 385whp. I have been running BR8ES spark plugs. Honest have to say these spark plugs only last 1 oil change from my experience and kinda annoying. Im want to try iridium plugs.

My questions : Are iridium just as good as copper in performance but last longer?
Is NGK BPR8EIX the right step colder for my performance?
NGK or Denso?
Iridium: does it need gapping?

Or should I just stick with copper and live with it.

 

Stick with the copper.

 

Bpr8es

 

What he said!

 

but whats the correct gap for evo 8? im boostin aroud 21 psi now.
its at 28 currently, im thinkin lowerin it to 24/26.

 

I would just close up the gap some to like .023 and make sure the grounding strap is parallel to the center electrode surface. When you bend the ground electrode over to close the gap it tends to make it an uneven surface that wears faster and opens the gap.

 

Copper is fine, but there is nothing wrong with the stock Iridiums. I was using my stock plugs with 38,000 miles on them, running 30psi on stock turbo with E-85. I just recently starting to get some misfiring. I replaced the plugs with another set of stock Iridiums and all is well again...boosting 30 psi on E85.

Again, a matter of choice. Pay less for the copper, but change more often. Pay more for the Iridium, but change less often.

 

To the best of my knowledge; yes.

The general guideline is one step colder fo every 75-100 hp added. Go for the 9 heat range.

I have never had a problem with NGK's.

Yes, you still need to have the right gap.

Your choice.

 

my evo as of right now pushes 25 pounds of boost and anytime i would lay into boost or try and do a pull it would cut off power, i replaced the spark plugs with ngk bpr8es and it fixed the issue for a little bit but it still cuts power and feels like the spark is being blown out, after realizing that i never gapped the new spark plugs i found out they come pre-gapped to .031, obviously that could most likley be my issue and i just need to re-gap them to .020-.022, but i just want to get some feed back and see what other things could potentially cause they loss of power, granite this is my first evo and it just shipped in yesterday.

 

that gap is to big, stick to .020-.022. Im running BPR7ES on 28psi boost 400 HP with spoolin up COP

 

do you think that could most likely be the issue?

 

I had no spark issues on the stock turbo pusing 25psi with .020-.022 gap and I was using BPR7ES. If regapping doesn't work try a hotter plug. IIRC BR7ES is colder than the BPR7ES.

 

P is for projected tip. The non projected is colder, correct.

IE
BPR7ES is 7 heat range
BR7ES is like 7.5 heat range
(With NGK higher number colder the plug)

9 heat range is way cold, not needed until large power.

 

after re-gapping the spark plugs the issue got a little better but not gone away completely and now everytime i let off the gas the car dies, i'm starting to think i'm going to need a tune at this point.

 

Are you logging? If so, what are your fuel trims like? What is your afr when the car is dying?