whats that?

If I boosted my engine I would probably run one step colder. (Japanese plugs: Colder = bigger number)

A 7 is a colder plug than a 6 FYI.

SST = Special Service Tool.

Ok, so I did a lot of research this morning. Thought I would share my findings.

The OEM plug is a Denso ZXE27HBR8, which will tell us all about the design of the physical plug.

ZXE - Thread Size x Hex Size - 12mm x 14mm, .55mm Iridium
27 - Heat Step - Equivalent to an NGK 9, Champion 4.59, or Bosch 2
H - Thread Reach - 26.5mm
B - Electrode Design - Triple ground electrode
R - Resistor
8 - Gap - 0.8mm (.032")

Now, with that knowledge, we can "build" a spark plug to our needs. As a general rule of thumb, for every 75-100 hp of FI, you should go one step colder in your plug. This will be your biggest concern when finding a model to fit your needs. One step up in Denso land would be ZXE31HBR8.

Unfortunately, I haven't been able to find any equivalent plugs with those dimensions. Denso, themselves don't even list them. I think it was a completely new model. It's odd to find spark plugs with 26.5mm reach.

The guide to the Denso part number spec is here (pg 12).

NGK lists a spec here.

Hope this helps everyone!

Makes it sound easy I wish I could see a video of how easy it really was

I don't think its easy, I think it requires TONS of patience. I do think its easier than lifting up the engine!!

What is this trollish information you speak?

Oh, sorry, let me translate...

Dude, Denso sucks ass. It sucks so much that other manufacturers haven't even made replacements for it. I bet that it costs like 20$ per plug from the dealer, too.

Just take your spark plugs out. Who needs that crap? You'll make more gains from the weight reduction alone.

...but really, it's 19.xx $ from the dealer.

I'm an NGK guy myself. I find that the more linear powerband and less heat you get from NGKs over Densos is more than worth the lower horsepower number they ultimately produce.

if its not avail in NGK, I'm fine with denso quality

money is fine for the part, I just want to know someone else has done this ZXE31HBR8 before I buy it

Done ginea piggin for a minute

Gem, that model isn't made yet.

The spark plug? It is, but it's really pricey being a RACE plug. I don't think anyone really wants to pay about $90 per plug. We'll test some out real soon though! :)

Regards,


Bob @ Drift-Office, LLC

Link? I couldn't find it on the google.

I have a customer running the HKS 50003-M45HL plugs, made by NGK with good luck. Not sure if they alone were an improvement though as we did a bunch of other things at the same time.

http://www.hks-power.co.jp/en/produc...ies/index.html

https://sphotos-b.xx.fbcdn.net/hphot...45736924_n.jpg

We are using the HKS fire on our own FR-S and S2000. They are great plugs!