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What Plugs Do You Use?

Tix

Tix

New member
I've done a general search but failed find listings of supported plugs for our bikes.

I'm looking to make more power and eventually get the front wheel up.


What do you guys run?
What would you suggest?
 
I run the iridium also but because they last longer between changes, the plugs in this thing aren't exactly easy to get at.

I know some ppl with say otherwise but I have never seen any HP/Torque gains from any kind of plug alone. All smoke and mirrors IMO.
 
question

9 Lives said:
I run the iridium also but because they last longer between changes, the plugs in this thing aren't exactly easy to get at.

I know some ppl with say otherwise but I have never seen any HP/Torque gains from any kind of plug alone. All smoke and mirrors IMO.
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Whats the model # on those plugs? All I found where the stocks on the ngk sight. Also thought about denso iridium but cant figure on which ones I'd get.
 
Thanks for the input guys.

I've used the Iridium pulgs in my old STi and with a tune, they did help make more power. Interesting to see what will happen with the 8. ;)
 
9 Lives said:
CR9EIX, CR9E is the copper core ones, the IX is for iridium.
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I run the CR9EIX plugs as well...I noticed a tiny difference when I first jump on the throttle (which isnt all that often) but with my stock plugs there was a tiny lag in throttle response. I find these plugs have helped with that slightly. Its still there a bit for me, but just ever so mildly now.
 
Dont use them but BRISK SPARK PLUGS AR10ZS Are one more that fit the fz8
i will stick with ngk tho!
 
I'm curious, how does a different brand spark plug make more power?
On older, carb'd engines, with coils, I can totally see that, but on an engine that is computer controlled in ignition, air and fuel, how can a plug make a difference that you can notice. I supposed if the engine is tuned, and runs on higher octane gas, it is conceivable that it would need a hotter plug, but stock..I dont understand. I'm all for it if its true. Can one of you more knowledgable guys help me understand please.
Thank you
 
I put em in so there is less chance of fouling...if I wanted power..I would put ngk plugs in...our bike comes with them.... The more I tear into this bike and upgrade it..the more I realize it already has pretty good parts on it..
 
Woody146 said:
I put em in so there is less chance of fouling...if I wanted power..I would put ngk plugs in...our bike comes with them.... The more I tear into this bike and upgrade it..the more I realize it already has pretty good parts on it..
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That makes total sense. Thank you Woody.
 
after 58,000mi the iridium plugs on my last bike looked like they had just come out of the box. supposedly iridium plugs create a spark hot enough to keep carbon & stuff form building up. also takes lower voltage to spark.
 
Yip, and those ones that are iridium, dipped in chromium with an added layer of molybdenum will not only blast of every piece of carbon in the combustion chamber and also give you 25% more HP and 50% gains in your fuel mileage. Copper is actually a better conductor than iridium. ;)
 
copper is a better conductor. change your copper plugs at 10,000mi. or never change plugs again. a broken ring & worn valve guides kills all bets. im just sayin if your engine isn't passing oil, iridiums have a longer service life. copper is a better conductor!
 
AndyS said:
I'm curious, how does a different brand spark plug make more power?
On older, carb'd engines, with coils, I can totally see that, but on an engine that is computer controlled in ignition, air and fuel, how can a plug make a difference that you can notice. I supposed if the engine is tuned, and runs on higher octane gas, it is conceivable that it would need a hotter plug, but stock..I dont understand. I'm all for it if its true. Can one of you more knowledgable guys help me understand please.
Thank you
Click to expand...

Disclaimer - my engine/combustion theory is based on modifying my GTP and Vette, but still seems applicable here.

Besides what has already been mentioned on longevity of the plugs (Iridium>Platinum>Copper) the difference is mostly heat dissipation properties. A tuned engine with higher octane gas would benefit from a larger "hotter" spark, yes, but actually a colder plug. On my GTP when I increased the boost from the supercharger and added more timing (to increase horsepower), I had to run colder plugs. Two full heat ranges colder actually. As temperature increases inside the combustion chamber you run higher and higher risks of pre-ignition (AKA knock, where the air fuel mix ignites from the heat and pressure before the plug fires). Obviously this is terrible for the engine.

So if you aren't using a PCV or getting your ECU flashed, plug longevity is your only real consideration. Once you start running low octane fuel in extreme heat, or messing with fuel and spark tables, the heat range of your plugs could really matter. I do not know how the FZ8 ECU senses or deals with knock, but my car dramatically cuts power and enters 'limp home mode'. Anyone here know what the 8 does in that situation?
 
mrarmy300 said:
Disclaimer - my engine/combustion theory is based on modifying my GTP and Vette, but still seems applicable here.

Besides what has already been mentioned on longevity of the plugs (Iridium>Platinum>Copper) the difference is mostly heat dissipation properties. A tuned engine with higher octane gas would benefit from a larger "hotter" spark, yes, but actually a colder plug. On my GTP when I increased the boost from the supercharger and added more timing (to increase horsepower), I had to run colder plugs. Two full heat ranges colder actually. As temperature increases inside the combustion chamber you run higher and higher risks of pre-ignition (AKA knock, where the air fuel mix ignites from the heat and pressure before the plug fires). Obviously this is terrible for the engine.

So if you aren't using a PCV or getting your ECU flashed, plug longevity is your only real consideration. Once you start running low octane fuel in extreme heat, or messing with fuel and spark tables, the heat range of your plugs could really matter. I do not know how the FZ8 ECU senses or deals with knock, but my car dramatically cuts power and enters 'limp home mode'. Anyone here know what the 8 does in that situation?
Click to expand...


Probably dies honestly..just speculation tho
 
I won't do anything, it doesn't have a knock sensor. Motorcycle EFI systems are not nearly as advanced as cars.
 
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