[N54 TuNeR]

I find my stock bosch plugs run smoother then my ngk 5992 plugs. One suggested to index them. If so which way you want them to face? The open side downward?

[CHECKERED]

I did on mine after having some lazy timing on #2 and sometimes on #4

the reason is because the OE Bosch plugs have shallow ground electrodes so it doesn't matter how they are installed, however on the NGK 5992, the ground electrode is deep and protruding, so it needs to face away from the fuel injector.

I suspect that if it faces the injector directly you end with uneven flame front which causes lower timings on the cylinder compared to others

[Ilma]

I just tried the NGK's and they idle really rough on cold startup.

After about 30 seconds they smooth out and once the car is warmed up they feel as smooth as the Bosch OEM's.

I gapped them to 0.22" but wonder if that is too tight of a gap and contributing to the rough idle?

[mikenazz]

I've got the ngk gapped to 0.7mm runs perfect idles fine. Feels better than my old oem bosh plugs.

[N54 TuNeR]

Checkered sent you a PM.
Think Checkered is right with how they sit in head.i without indexing I tried all ngk plugs and the open side of plug sits anywhere between12-4, think they should sit the opposite.im not 100% sure

[Ilma]

Originally Posted by mikenazz

I've got the ngk gapped to 0.7mm runs perfect idles fine. Feels better than my old oem bosh plugs.

0.7mm = .0275in.

So mine being set to 0.20in might be causing the poor cold start.

Funny because PTF's website actually recommended this gap in the first place.

Anyone else gap their NGK's at .027?

[135Pats]

Originally Posted by Ilma

0.7mm = .0275in.

So mine being set to 0.20in might be causing the poor cold start.

Funny because PTF's website actually recommended this gap in the first place.

Anyone else gap their NGK's at .027?

IMO that's a bit wide for a FBO-type car. On stock turbos I went through a few sets of NGKs gapped at .022-.024, never had an issue.

Now they're gapped to .019, which is fine once the motor has some heat in it. But cold starts w/ E85 when it's below 50F is rather comical. Sometimes the car will cut out alltogether if it's at/around freezing

[CHECKERED]

Originally Posted by Ilma

I just tried the NGK's and they idle really rough on cold startup.

After about 30 seconds they smooth out and once the car is warmed up they feel as smooth as the Bosch OEM's.

I gapped them to 0.22" but wonder if that is too tight of a gap and contributing to the rough idle?

colder plugs will always have rougher idle, and worse on ethanol. If running any ethanol concentration wait 45 seconds to 1 minute with key in the ignition and all dash lights on, before stating the engine, it will preheat the injectors and start up idle should improve.

Originally Posted by N54 TuNeR

Checkered sent you a PM.
Think Checkered is right with how they sit in head.i without indexing I tried all ngk plugs and the open side of plug sits anywhere between12-4, think they should sit the opposite.im not 100% sure

Saw it, you can use 12mm spacers, but I used a different technique:

1. I marked the ground electrode with a sharpie on the white porcelain,
2. First hand tighten each plug, for a full seat the plug needs exactly half a turn (180 degrees) for proper torque,
3. knowing #2, if the ground is facing away from the injection (after hand tightening) and I would do half a turn it will improperly seat, so I try different plugs until the ground is facing the injector, and then tighten fully so it faces away.
4. a. If no plug works in a particular cylinder, you can slightly over tighten by going 200-220 degrees
4. b. What I did with a local friend is remove one of the washer from an old plug and double up on the washers.

[ferocity02]

Originally Posted by CHECKERED

colder plugs will always have rougher idle, and worse on ethanol. If running any ethanol concentration wait 45 seconds to 1 minute with key in the ignition and all dash lights on, before stating the engine, it will preheat the injectors and start up idle should improve.

I'm 99% sure the injectors in the N54 don't have any preheating.