Iridium Spark Plug Gap

[Steve C.]

Hey Gary, according to the Denso web site, the Iridiums come pre gapped and shouldn't need adjustment unless you have a modded engine.  IIRC that's what I've done on my bikes, just swap 'em out and let her rip.

http://www.densoiridium.com/faq.php


Steve C.

[Marsh White]

Steve,
So what's the deal with these plugs?  I've just been using the stock NGK plugs.  Can those of us without new coils and wires get a benefit from these plugs?

[Steve C.]

Marsh, I've never done back to back dyno runs with OEM style vs Iridium plugs but it's what Hank put in the motor when he built it for me so I can only imagine they are worth a few ponies at high RPM.  He doesn't believe in spending $$$$ that don't equal horsepower.  The biggest improvement I've found so far is changing to the accel coils.  No dyno runs but she certainly starts easier which is a good thing since the FCR-39s don't have a choke circuit.

[Gazza]

Thank you Mr. Conklin, sir.  I will pass that on to my friend who discovered said iridium units in the head of his Futura that was running a little funny.  Here she is and not looking too bad for 54,000 miles.




Darn nice site here, Fluffy!!   

[Mark Olson]

I used to run stock ngk but switched to 1 step colder plug to help with heat and pinging in the summer, some riders switch back and forth depending on weather.

[ogmudbone]

my 85 FJ 1100 is bone stock right now...i switched to iridium plugs and gapped them to regular specs...made a huge difference...way smoother idle, better response,negligable mpg increase. it runs far smoother and just feels better at every rpm level now.


OGmudbone

[FJ Flyer]

Just ordered a set for the FJR.  NGK site gives you the gap.

[scapello]

Did you get your plugs by now? Let us know what you think, I am going down the same route.

Steffen

[FJ Flyer]

Got the plugs and they're sitting on the bench.  Hoped to do them today, but the damn water softener wasn't cooperating after changing out the motor, gear cam, and seals.  Try again tomorrow night.

[mikeholzer]

I'm stepping up to the Iridium plugs myself. I can't seem to get better than 38mpg out of my 92 FJ; I think that the previous owner neglected a lot of the maintenance on this one.

Maybe this will help with the rough idle, too.


Mike

[tqmx1]

Guys I hate to say it but Iridiums & Platinums are a waste of money for somthing like the FJs. The main reason for them is there long life they will not give you any more power.

The long life is nice for Cars/bikes & other engines where the plugs are a BITCH to get to (the FJ is not one of them ) so any of the $3. a piece standard plugs and change them about every 8000 miles you will be $$$ to the good.

[Dan Filetti]

All I know is that a fresh set of plugs in my buddies' BMW R65, makes it clearly very much faster, and more enjoyable to ride with (the old plugs looked ok coming out not all sooted up or too dark/ light).  If there is such a difference between an old plug (10K miles) and a new one, maybe a fancy schmancy plug would be even better. 

I'd be curious to hear the feedback from those that are trying them in an FJ.  I can't see the harm, and who knows, maybe the spark is bigger, and makes for a better burn -or some such.... Please do report back, for those of you that are trying them.

Dan

[tqmx1]

Dan, You are comparing a old set of spark plugs to new Yes there is going to be a differance.

You were saying the plugs were all sooted up that is telling me he is running rich (put smaller jets & bigger needles in it and solve it's problem) As for the FJ get a set of NGK DPR8EA-9s and then a set of the Iridiums or Platinums and take it to a dyno and run back to back pulls. My bet is there will be less the .5% differance in Hp & Tourque the only dirrerance you will feel is how much fuller your wallet feels with the $$$ you saved

It takes X amount of current to jump the plug gap once it jumps you could have 1.000.000 volt coils and it would not make a bit of differance (the only thing is you could run a wider plug gap to ignite a leaner mixture charge)

Kim

[scapello]

Here is an article that might be of interest.

I think the benefits might be minor but only the best for our girls, right?



http://www.spark-plugs.co.uk/pages/technical/iridium_spark_plugs.htm

[tqmx1]

It's a waste of hard earned $$$ but do what you want. Your combustion chamber wont know the differance.

The only time the high buck plugs come into there own is on HIGH boosted Supercharged or Turbocharged engines +20lbs.