According to Honda Tuning Magazine, Oscar Jackson at Kraftwerks discovered that the swapping to a slightly shorter spark plug in the GE will eliminate a hotspot and let the engine gain a few horsepower.
Project 2009 Honda Fit - Denso Iridium Spark Plugs - Honda Tuning Magazine

Not sure if there are any downsides but you have to wonder why Honda didn't use these plugs from the factory.


**edits**
Something went screwy when I tried to edit before, but anyway.

If you look at the the dyno graph you can see that the plugs used are the IK22.
Also note the nice gains from the Takeda intake, first trustworthy third party dyno I've seen of any intake.
Is this a sign of things to come from Kraftwerks? I hope so

 

Wonder how much of a beast the actual plug install is?

Direct link to said plugs...

Kraftwerks USA Products

 

haha i think he discovered it while Kraftwerks was holding a "Fit Meet" i was at. They tried it on a GD3 and amazingly it gave an instant hp gain! i think from like 99whp to like... 104? haha but with a fit, it needs all it can get i guess

 

I bought these plugs after reading the article. I haven't installed them yet though.

 

If only its wasn't a product sold by the same individual in the article. I would be better sold on it. Although rethinking on it: has there ever been a check on the effect on fuel economy with these? I'd be curious.

 

Ah that's probably the downside. Fuel efficient = lean = hot.

 

Copied and pasted from my garage thread.

Received the Denso IK22s in the mail today and just finished installing them. Will go for a quick run. First will describe the procedure.

Removed the upper and lower cowl to make it easier to get to, if you have small enough hands you might just be able to do it without removing the pieces, but would be pretty much a pain in the ass.

First thing is to remove your windshield wipers which are held in place by (14mm) nuts. And undo the wiper fluid hose at the junction next to the cowl. There are 2 small plastic clips holding the upper cowl cover as well as about 6 or so clips, that you can see if you remove the strut covers, that you don't have to really worry about getting out, just pull up on the cowl once you remove the 2 small plastic clips. After the upper cowl is off, there are 6 (10mm) bolts holding the lower cowl in place, plus another 3 (10mm) bolts that fasten the wiper assemblies to the lower cowl. I can't be certain if it is exactly the same on the left-hand drive models, but I'm pretty sure it would be. Once both are off you still have to somewhat makeshift your way around, but not hard whatsoever. The coil packs are attached by (10mm) bolts and the spark plugs are (16mm) or (5/8"). Remove your coil packs and plugs and reverse the whole procedure. I do it one at a time so as to not mix up the coil packs, yes they are the same across the board, but I would rather have each cylinder to have the pack it originally had.

Sorry I didn't take any pics, but it is already dark here and I just couldn't wait till the weekend to change them out.

 

I don't mean to be a broken record, but you do not need to remove the cowl/assembly/etc to replace the plugs. I did the job in 15 minutes "by braille" with only a basic knowledge of spark plug replacing. You can, but you can also tack on an extra 30 min for taking off the assembly and 30 min putting it back on. Plus, you run the risk of breaking the clips on the cover.

 

Well maybe my hands are larger than yours or something, but trying to get behind the 2 cylinders to the right was not happening. I don't see how one would break the clips on the cowl unless they are a complete 'Grape Ape'.

The whole job took me 45 minutes, so I spent an extra 30 minutes longer than you did, but my hand was not fitting around the assembly, maybe the left-hand drive is easier to reach around compared to right-hand drive.

 

Has any one tried this on a euro GD1 (1.4 non-vtec), results?

Also, any one point me to a link for these "shorter" spark plugs?

 

IK22

This is where I purchased mine from, came up to $44 shipped.

Also in the 2nd post in this thread there is a link to Kraftwerks page selling them.

 

So this intake and these plugs and its like I found a hidden turbo!?

 

so 555 sexy drive did you notice any improvements in performance or detriment to fuel economy

 

These plugs come pre-gapped?

 

Plugs are pre-gapped. Honestly I can't feel any improvement in performance, but if they do only generate 2~3hp, that is something you wouldn't really be able to feel. Even if timed against the regular plugs, the actual drop in time would not be very significant (say from a 25~75 spurt). Fuel economy hasn't gotten worse or better, but mostly my foot is the reason for that.

On a side note to the fuel economy question, I actually seem to get better economy from leaving the TC in SP7 mode, as it can get up to speed much faster and easier to modulate the throttle at that setting.

 

Subscribed!!!

 

i have to agree w/ baylorbro here. u can actually reach behind from the passenger side of the motor....unless u have short arms. i'm 5'10, 200lbs so im not a small skinny guy...however i don't have super huge hands either. i unbolted the coilpack closest to the drivers side. question for BAYLORBRO: did you unclip the coilpack then uninstall...or just yanked out the coilpack? I had to kind of bend the boot to get it out and wasn't sure if it would damage anything. well, as bad luck would have it..i ended up slicing my finger pretty deep after removing the first coilpack. so since i had no bandages nearby(blood was gushing out a little faster than i expected and i was trying to attempt this on my lunch break in the parking lot), i decided to just wrap it up and attempt this on my next lunch break. at least i know its doable w/out removing the cowl....for me anyways.

so yeah, if you plan on just feeling around back there w/out removing the cowl...be careful. one of the metal plates back there is pretty sharp. i think i might've dripped some blood back there too so my fit n i are now blood brothers (no longer a one man wolfpack...lol).

 

someone pls confirm the effect on fuel econ,