Just changed my plugs, used the NGK iridium motorcycle BR*IEX plugs, but they didn't have any 7's in stock, so I'm running BR8IEX leading and BR9IEX trailing.

My motor is completely stock, but I will be installing a downpipe within a week or two. Colder plugs should be less likely to detonate, but foul more easily, but Iridium should make a better spark and last longer. I'm hoping the hot summer weather will play a factor and prevent fouling. It was 100+ degrees yesterday while I was changing them.

The BR-IEX's were $7.00 each at my local motorcycle shop , and they had a thin-wall wrench to use for installing them. I had to grind the walls even thinner.

I just wanted some feedback, has anyone tried this? Is there anything I'm missing?

-scott-

 

Here are photos of the old plugs, I've never seen any as bad as these. I was under the impression that the dealership I bought the car from had changed them out, but obviously they hadn't. I wonder how long it was since the previous owner changed them...

Also I mis-typed the part number for the plugs I installed. It's BR8EIX leading and BR9EIX trailing.

I'm thinking the colder leading plugs might be a bad idea, these leadings were pretty dark. The rear rotor wasn't quite as bad, but same basic thing, lighter trailing, darker & more gunk on the leading. Everything feels fine so far, but I'm planning on checking these ones in a thousand miles or so, will post an update then...

-s-

 

I removed the BR*EIX plugs today. Since I added them, I drove the car a few hundred miles, installed a downpipe, and drove another few thousand miles. The plugs have just over 3,000 miles on them.



-s-

 

Interesting. How was the idle after that many miles?

 

Also from my understanding Iridium plugs just last longer but copper still gives the best spark. Platinum and Iridium ive heard is just so they last longer.

 

That photo shows the plugs as if you were looking at the motor from the drivers' (left) side of the motor:
The idle with the BR*IEX's (w/ 3k miles on them) was fine, there was a bit of that 'puffing' sound that seems to come as the plugs get older, and go away right after you switch to new ones, but it was plenty smooth. I was mostly curious to see how they held up, being non-stock plugs and in different heat ranges than I had planned on using. It looks like 8's were good to use, I might try 9's next time, because to me the leading's look like they were getting too hot, or at the very least could afford to be dissipating more heat.

I do have a slight exhaust leak at the downpipe >> cat junction, and it's causing the car to overboost a bit (+1-2psi at full throttle). That could be causing the apparent hot/lean condition, though I'm not sure.


I switched back to stock copper plugs, BUR7EQ and BUR9EQ, mostly because I want to get a feel for what the car's like with fresh stock plugs in it. The wires are old and I'm looking into either buying a set of NGK's or making a custom set of MSD's, if I can find some that will match with the BR*EIX's threaded end.

-s-

 

When your idle gets "puffy" as you say you are probably losing power and the plugs need changed. It's a gray area though as to how lumpy the idle is. I normally notice this after 3K or so on stock plugs.

As for the exhaust leak that shouldn't make any difference in boost or a hot/lean condition. I have recently developed a super bad exhaust leak and other than sound it has no impact.
dis1

 

miss post