Plug inspection
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From: San Antonio, Texas
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.



These are NGK iridium plugs so before anyone says WTF, yes the electrodes are supposed to look like that.
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.
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.
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.
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.
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From: Chicago. (The less-murder part.)
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.
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.
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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.
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.
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From: Fake Virginia
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
http://dirtbike.off-road.com/dirtbik....jsp?id=332655
Joined: Sep 2005
Posts: 34,402
Total Cats: 7,523
From: Chicago. (The less-murder part.)
Joined: Jun 2005
Posts: 19,338
Total Cats: 574
From: Fake Virginia
Thread Starter
Elite Member
iTrader: (15)
Joined: Dec 2007
Posts: 4,847
Total Cats: 27
From: San Antonio, Texas
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
http://dirtbike.off-road.com/dirtbik....jsp?id=332655
https://www.miataturbo.net/forum/showthread.php?t=22322
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