ZX-Tex

iTrader: (15)

So I pulled my plugs tonight to see how things are going in general, and to look for signs of detonation. Here is what I found, in order, cylinders 1-4. Only thing that concerns me are the very small dark specs on some of the insulators. Supposedly small dark specs are a sign of detonation, but not sure if this is what it looks like.

These are NGK iridium plugs so before anyone says WTF, yes the electrodes are supposed to look like that.

J.T.

I thought the dark specs were from minor oil blowby, thats just what I've heard though. Lotta carbon buildup tho

Bryce

iTrader: (24)

I've never actually seen what the signs of detonation look like, but that looks like it from what I've read. Tiny specs of oil and metal landing on and fusing with the porcelain and ground strap.

magnamx-5

iTrader: (7)

uhh dude you are fine stfu and drive bryce you wrong det looks worse

Bryce

iTrader: (24)

I stand corrected then

magnamx-5

iTrader: (7)

lol atmost i would switch to a stage colder plugs but his electrodes look good and there is no sign of damage. If you run abit colder plugs you will loose hp but the safety margin goes up a lil.

cjernigan

iTrader: (13)

What plug gap are you able to run with those iridiums? It looks huge compared to my current .025

samnavy

iTrader: (7)

Plugs look fine and carbon buildup indicates running slightly (safely) rich.

Hmmm... never thought about being able to run larger plug gap with iridiums. With COP's I'm running .040 on the standard 1 step-colder Autolites... maybe I'll pull them tonight and increase a little to test results.

Joe Perez

iTrader: (8)

Those plugs look gorgeous, ZX. Frankly, they're cleaner than mine (also Irridiums)

CJ- with stock ignition I used to run those at about .030", now with the COPs I've got 'em at .040". I've not tried going any further (maximum acceptable gap shouldn't really be a function of plug electrode construction) but you're right, those look huge.

m2cupcar

iTrader: (5)

I agree- I think they're fine. Similar to mine... maybe a bit richer

ZX-Tex

iTrader: (15)

Thanks for the feedback all.

They are gapped in the as-delivered state which is a large gap at 0.044". Reminds me I forgot to check the gaps when I pulled them, dang it. That is a large gap but I wanted to give it a try and so far the car seems to be running well. Granted I am only running at 7.5 psi right now while waiting for the clutch installation. When I increase the boost to 12 psi I may have problems as mentioned here in other threads and will have to close up the gap. Right now I am using the stock coils and newish NKG wires.

y8s

iTrader: (8)

if you want the real story, go do a power run and shut off the car as soon as you lift. otherwise you're not getting the "true story".

http://dirtbike.off-road.com/dirtbik....jsp?id=332655

Joe Perez

iTrader: (8)

...which I hear is really good for your turbo bearings.

y8s

iTrader: (8)

synthetic oil and doing it once in a blue moon probably wont do much

ZX-Tex

iTrader: (15)

Yes I agree. I was not looking for mixture feedback since I have the WB02 for that, arguably a much, much better tool than the old chop-the-ignition-and-coast-into-the-pits approach. I was more interested in looking for signs of detonation based on what I am doing in this thread:
https://www.miataturbo.net/forum/showthread.php?t=22322

Saml01

iTrader: (9)

Id worry more about stopping with no vacuum assist.