What spark plug gap?
 

I've been searching around and got a lot of answers to the same question :facepalm:

I just bought a set of NGK Power coppers. What should they gap?

So far i've seen people saying .045", .040", .039", .035", .030" and .020". Which one is it? I'm running stock ignition system so i assume the 45 is too much since thats more for COPs.

.035-.030"

Thank you sir :)

.025 was the most I could run on the stock coil. I run .050 with the Toyota cops. The seemed to blow-out in colder temps, so you may want to take .005 out if its warm out (but you're in Chi-Town so its probably cold).

This exactly...but my stock coil gaps were closer to 0.020...so I was in a real rush to get COPS.

I run the 0.041 gap with them as they come out of the box.

I gapped around .025 @ 14 psi before I got CoP.

so wait, its better to go less with the turbo otherwise it blows out?

I had my BKR7E's gapped to .030 and they worked great.
You want a smaller gap when turbo'd, yes.

unless you have a real ignition system where you can get away with .043" like me on my cheap ass Autolite 3922s

Definitely planning to go COP in the future;)

Does anyone at the moment makes COPs to order on here?

You have a 90. Brain made a big ass thread about doing it for the earlier years. Just follow that and I don't think youll have problems.

Us NB people don't have a step by step like that. Even though its similar its not the same AFAIK.

oh well

i would just like to get a premade one if anyone makes it. I did see the big thread with a step by step how to .

It's not better, it's a necessary compromise.

Larger gap is "better"...but it can blow out with stock ignition system at boost above about 10psi (for me). I think my coils were getting pretty damn tired at 240K miles...and COPS were like espresso for my motor.

What do you guys think? The lower right is number 3... 2nd to the back of the engine

it had some oil on the rim (the washer/gasket) but i dont know if its from when i did the compression test or whatever.

There was no oil on the tip or the threads of the spark plug.

Attachment 202657

Attachment 202658

Looks just a little lean.

I'm currently running .020. I tried .025 and got blow-out above 12 psi. Now I'm waiting for my Boundary/WeaponX COPS to arrive .... dreaming of big-gap goodness!!!

Just do it man.

I wanted to order some too...and then found all my COPS on eBay for $80 shipped and just started doing it one day...took an afternoon.

The big how to is much shorter when you clip out the parts you don't need.

god, how long has that been now?

Evan why dont you just toss in a tesla coil in there while you're at it :P

I've been able to run .035"-.037" on the stock 01+ coils + Magnacore wires + NGK race plugs.

Yeah i measured the stockers and they were about 37-38
i made the new ones 33

Recommended spark plugs/gap for 95 on 7psi, stock coils?

Was assuming to go with BKR7E's but unsure of a correct gap...

Guess there really is no definitive FAQ on proper spark plug choice and gap?

i'm running ~0.032 on BKR7E but thats with a blaster II coil and a distributor... its a little easier for me to upgrade than you guys :)

lucky :) lol very impressive car man!

anyone else running BKR7E?

Yes. Many people.

thats the standard plug recommended for turbo miatas

18psi,triple88a...thanks for the info guys.


Whats the recommended/common gap on those plugs on stock 1.8 coils?

.035-.030 is what mine are set to.

Whats stock plug gap anyway? Just for an N/A engine? (Not COPs)

I think its somewhere in the high 40's low 50's? Just guessing

Lol he did say NOT cops :)

from what i've found 35-40 is good.

Mazda specs the stock gap at 1mm because, that's right, they've got the metric system! If you do the math it's pretty close to .040" which is a nice easy number to remember.

Being still N/A I haven't felt compelled to run BKR7Es but I do run BKR6Es (one heat range colder than the stock BKR5E) because it hits the track a few times a year. On a totally stock street only car I don't see any need to run colder than stock plugs.

0.03937 to be exact. ;)
The OCD in me had to say something.

I ran .025 with the wrong spark resistor in my MS with stock '99 coils.

I just turbo'ed my car, with an HKS kit w/o intercooler boosted at 5,8 psi:

I bought NGK BKR7EIX-11 where 11 stands for the 0,043" gap...

It is the standard gap of the NA version, could it be too much?

I tried to boost @ 6,5 psi and i heard it knock, could it be because of the plugs' gap?

what if the gap is too much??

then you'll have spark blow out issues, and no spark = no boom = no detonation.

lol

i didn't really understood what you meant...

anyway I put the gap at 0,035"...

It went good...

I tried the car on the motorway and reached 6500 rpm in 6th gear at 225 kmh...

It seems it is good!!