anyone recomend spark plugs that are 1 step colder for the Z used for NA?

My engine is misfiring with my mods and I want to get this solved ASAP
I get the check engine soon light that comes on and stays on and it happens around 1-2k rpms

thx guys

BTW, power mods are:

Crawford package
JWT cams
nismo exhaust
tilton street clutch/flywheel
350 evo Final drive
UR pulley
JWT popcharger
350 evo throttlebody
TS ECU

 

I got mine from www.autocarparts.com

 

By the way they're Denso Iridium plugs

 

perfect, thanks! - someone told me Denso doesn't make 1 step colder so I wasn't sure what to get for a little there

 

I'm confused, so what is the part number of the Denso Iridum plugs that go in our cars? Is it the IK20's?

 

Yes

 

Great thanks!

 

IKH20 is the right part number for a Z, and its 2 steps colder than stock, not 1.

Adam

 

You might also want to look at NKG. LFR6A1X-11 A good source is Vivid. A my350z.com "sponsor". The price was right and got quick service.

 

Ok well I just ordered them last night - should I cancel my order - I need 1 step colder, not 2. Maybe I can just wait until I get them and find out what part number they are - seems like false advertising or something if they really aren't 1 step colder

 

after my ecu flash Tadashi at Technosquare suggested I move to the 1 step colder plugs as well. I got them at a nissan dealer in his area and Technosquare put them in for me. I do not know the part number but they work great!

 

I say the IKH20's are 1 degree colder and the IKH22's are 2 degrees colder.

 

What about the IKH16's?

 

bark, that z is f'n nice!

 

Alright, I gotta ask. What does it mean to be 1 or 2 steps colder??

 

The IKH16 is equivalent to stock.

 

TS is taking my car on Monday to research the 2005 ECU and come up with a tune.

At the same time -- they will be installing the following:

Crawford Plenum
Crawford Headers
Crawford Cats
Nismo Exhaust
350 Evo Throttle Body

Of course, TS will be doing a full tune for my package as well.

Right now I am passing on cams. Maybe later -- but the stuff above is plenty costly. Will I need cooler spark plugs????

BTW, I will be getting before and after dynos.

 

Does anybody know the actual heat range rating number for the stock plugs? I have a set of HKS Superfire Iridium plugs, heat range 8, sitting in my garage.

 

Skrill, you might not need them, but you never know

I have those same mods for the most part with the addition of jwt cams, tilton clutch, UR pulley and I need the colder plugs. I was told it's mostly the tilton that's causing it on my setup with how it's interacting with the mods

 

mike - got your fax this AM. The way I read their literature though is that IKH16 is stock temp range. One step colder would be an IKH18, but there is no such plug. IKH20 is the next one they offer, but its 2 steps away from the stock temp range.

Now, that does not mean it is not an acceptable plug to use.

However the better question I guess is why you are getting any misfires of any kind on the car given your mods......there should be absolutely no need for a colder plug on an NA setup unless you are bumping compression, etc

Adam