[ocN55]

Originally Posted by Pparana

you need a deep well spark plug socket, just get one from ecs or another bmw shop,

one thing to note the torque spec is pretty high on the plugs, since the motor is direct injection. I forget the number, but it is more than hand tight.

Does the normal 14mm 12pt socket work? Looks like the copper plugs are 6pt.

[Pparana]

Thin wall is needed, http://www.amazon.com/CTA-Tools-2376...rk+plug+socket

[Mywifes335]

Originally Posted by ocN55

Does the normal 14mm 12pt socket work? Looks like the copper plugs are 6pt.

Wait a sec.... With everything that's been said? What's best for power and ensuring no misfires?

- 1 step colder iridium (ocn55 reco)
- copper (which ones? Pparana reco)
- n20 (?)

You guys are all familiar with my mods...

[dt20011]

I'd give the N20 (ngk) plugs a shot.

[Mywifes335]

Originally Posted by dt20011

I'd give the N20 (ngk) plugs a shot.

Is that what you ran?

The stock ngk iridiums?

[dt20011]

Yup.

[DfVgyCjmFQnu]

Originally Posted by Taunto

it is possible but hard to tell for me without actually seeing the vehicle.

a good note to everyone tho is if your vehicle is miss firing to have it inspected as soon as possible. The electronics on our cars and almost any newer vehicle these days are very fragile.
I have seen a couple times now where a prolonged a bad ignition coil has caused internal damage to the DME and required a new DME followed by programming.

if you have a bad or faulty ignition coil you will notice right away because the vehicle will be miss firing constantly.

the only way to verify a coil is bad besides hooking up a oscilloscope is identify what cylinder is miss firing and without Removing the spark plug swap that cylinders ignition coil to a known good cylinder... clear faults do a key cycle then restart the engine till the check engine light comes on or vehicle begins to miss fire for a little bit. Recheck fault codes and see if the miss fire followed the ignition coil to the other cylinder

Thank you very much, I owe you a beer.

The car is running great since the new plugs, no problems whatsoever, idle and under power is very smooth. I think I am good for now. Thanks again!

[Pparana]

Originally Posted by Mywifes335

Wait a sec.... With everything that's been said? What's best for power and ensuring no misfires?

- 1 step colder iridium (ocn55 reco)
- copper (which ones? Pparana reco)
- n20 (?)

You guys are all familiar with my mods...

Depends on what you want, copper most power, most Maintence. N20 is what I would run if I was In a 91 octane state.

[Mywifes335]

Originally Posted by Pparana

Depends on what you want, copper most power, most Maintence. N20 is what I would run if I was In a 91 octane state.

I'm in 93 octane states all the time. Really looking for most reliable power.

Looks like N20 is popular with by power guys.

[Drpoomanchu]

Originally Posted by Mywifes335

I'm in 93 octane states all the time. Really looking for most reliable power.

Looks like N20 is popular with by power guys.

Have you tried the N20 plugs or did you go a different route..? After much searching it seems the old 5992's now NGK ILZKBR7A-8G are very popular on N54 tech and come well received by Terry running JB4. Im debating between the copper core 4786's, old 5992's, and N20's. Correct me if im wrong but all 3 of these plugs are one step colder in heat range than our stock plugs which would seem like the sweet spot running roughly 100hp over stock. I would like to know the latest info on plug choices before i replace mine here soon. I will be FBO this spring running stock turbo and fueling system 3-4 gal E85 to 93oct map 5.

[Mywifes335]

Originally Posted by Drpoomanchu

Have you tried the N20 plugs or did you go a different route..? After much searching it seems the old 5992's now NGK ILZKBR7A-8G are very popular on N54 tech and come well received by Terry running JB4. Im debating between the copper core 4786's, old 5992's, and N20's. Correct me if im wrong but all 3 of these plugs are one step colder in heat range than our stock plugs which would seem like the sweet spot running roughly 100hp over stock. I would like to know the latest info on plug choices before i replace mine here soon. I will be FBO this spring running stock turbo and fueling system 3-4 gal E85 to 93oct map 5.

I used the N20 plugs (copper, according to NGK) right off the bat with the PS2 turbo setup. Car has been running perfectly. I'm not sure what the temperature number is, however. The N20 plugs are the NGK SILZKBR8D8S and the stock N55 plugs are ZR5TPP33S. My guess it that the first 8 versus the 5 in the N55 plug code means it is 3 steps colder.

http://www.jegs.com/i/NGK+Spark+Plug...YQDBoCIZTw_wcB

I might not be 100% right, but if your car is not running an upgraded turbo, I'd stay with the stock plugs or whatever Terry recommends. But generally, from all the tuners I've spoken with Copper is a better conductor than Iridium. Iridium lasts longer.

BTW, IF you get the N20 plugs, make sure to gap them yourself to the right N55 gap. They are NOT pre-gapped for the N55.

Hope this helps.

[Paisano]

What is the reason for N20 spark plug superiority when the N55 is tuned?

[amw896]

I think someone above mentioned they are optimized to handle higher boost and temperatures better. They operate in a colder temperature range.

Originally Posted by Paisano

What is the reason for N20 spark plug superiority when the N55 is tuned?

[Paisano]

Originally Posted by amw896

I think someone above mentioned they are optimized to handle higher boost and temperatures better. They operate in a colder temperature range.

I saw the post but I should rephrase my question. Other than being gapped differently, are Laser Iridium or is the N20 a combination of some other compound? I'm sure the higher boost levels experienced by N20 spark plugs have something to do with it.

[amw896]

I think it was also mentioned above that the N20 plugs are copper vs the N55 being iridium.

Originally Posted by Paisano

I saw the post but I should rephrase my question. Other than being gapped differently, are Laser Iridium or is the N20 a combination of some other compound? I'm sure the higher boost levels experienced by N20 spark plugs have something to do with it.

[Paisano]

Originally Posted by amw896

I think it was also mentioned above that the N20 plugs are copper vs the N55 being iridium.

If that's the case it would make a difference in spark plug temperature, albeit at the price of changing the plugs more often.

[SerenVoX]

I just ordered the 228i plugs/ NGK 739-SILZKBR8D8S Gonna give them a try. I'm stock turbo but am FBO/ 93 and few gallons of E

[bryan_G01]

i'm running the s55 plugs, 15k miles, no issue.

So in a pinch, you can run the n20 or s55.

[Kolyan2k]

What about M2 plugs? They seem to be different from M235i

[Dylan86]

It's time for new plugs on "black mamba". Should I go with the N20, or S55 plugs, guys? Car is FBO/meth.

Cheers

[Drpoomanchu]

Originally Posted by Dylan86

It's time for new plugs on "black mamba". Should I go with the N20, or S55 plugs, guys? Car is FBO/meth.

Cheers

Did you ever make a decision on plug choice. I have S55’s waiting for install but I think I’m going to sell them and opt for the N20’s due to what I have been reading lately. The part # (NGK SILZKBR8D8S). I have read NGK and Bosches heat ranges differ and do not directly correlate. Running between 80-100hp more than stock should decrease heat range by 1. The N20 plug is 1 step colder than the stock N55 plug. The S55 plug also has the same heat range as the stock N55 plug. So anyone of us FBO folks should benefit from a colder plug. The N20 plug gapped to .020 - .023 depending on boost seems to be the way to go.

[SteveInfante]

I just ordered my set of plugs from Amazon. Gotta love when they are on sale and you get 2 day shipping. Got the N20's because I have the N20....ha ha.