Spark plug gap for 2.4 pulley

[efnfast]

I can't figure out what the "best" spark plug gap to be for a 2.4 pulley would be in my situation.

I am 3,500ft above sea level, so I loose 2lbs of boost compared to stock (normal max boost I see is 12, with a periodic second spurt to 13 before it falls back to 12). But then the pulley gets me that boost loss back (I also have tw 67 mm TB and off-road H, but I assume those 2 cancel eachother out).

I see the recommended range is 0.028'' to 0.032''.

Should I set it at the lower end? Or assume the elevation and pulley cancel each other out and go towards the higher end since my boost levels will be closer to stock?

 

[Catmonkey]

I think you could get by with .030". Close them up too much and it can effect idle qualify to some degree. They do open up over time.

 

[efnfast]

I decided to go with 0.028'' ... I was expecting worse idle than with the stock plugs but I can't tell any difference actually (NGK BR7EF plugs) so I'm happy

 

[WicK]

I can't figure out what the "best" spark plug gap to be for a 2.4 pulley would be in my situation.

I am 3,500ft above sea level, so I loose 2lbs of boost compared to stock (normal max boost I see is 12, with a periodic second spurt to 13 before it falls back to 12). But then the pulley gets me that boost loss back (I also have tw 67 mm TB and off-road H, but I assume those 2 cancel eachother out).

I see the recommended range is 0.028'' to 0.032''.

Should I set it at the lower end? Or assume the elevation and pulley cancel each other out and go towards the higher end since my boost levels will be closer to stock?

So what did you go with?

 

[2011 gtcs]

Just put NGK BR7EF plugs in gapped at .30 and call it a day.

 

[WicK]

Just put NGK BR7EF plugs in gapped at .30 and call it a day.

Do we know the stock number? Was looking to order them from advance autoparts. The tr6s are 4177 but was wondering what they are for 13 gt500s.

 

[WicK]

I feel like there's so much debate as to which plug to run. Running 2.4 pulley 123 jlt, offroad h and soon to have a 67mm vmp. I have the tr6s in right now but thought maybe going with the br7?

 

[efnfast]

So what did you go with?

see above - BR7EF( #3346) gapped at 0.028'' ... no issues. Idles well, drives hard. I'm happy.

I'm using T6s in my 2004 and am happy with them.

I only went with TR6s in the 04 because that was the flavor of the day and it seems that the BR7EF is the most popular 13/14 plug.

 

[GTMAN212]

TR7IX plugs I gapped to .28 with a 2.4

 

[Norton]

FWIW, I'm happy with NGK TR7-IX (3690) gapped @ 0.030".

Mods include JLT 127mm CF CAI, CFM Twin Jet 67mm TB, VMP 2.4" Upper, 90mm Idler, BPS Oversized & Ported Plenum/Elbow, VMP Triple-Pass Dual-Fan H/E, and Reische 170' Tstat.

 

[WicK]

I just want to say thank you all for the help! I'm sure it will help others as well in the future! And ty all for the parts numbers!

 

[WicK]

FWIW, I'm happy with NGK TR7-IX (3690) gapped @ 0.030".

Mods include JLT 127mm CF CAI, CFM Twin Jet 67mm TB, VMP 2.4" Upper, 90mm Idler, BPS Oversized & Ported Plenum/Elbow, VMP Triple-Pass Dual-Fan H/E, and Reische 170' Tstat.

Super helpful! I think I might pull out my tr6s and see how the BR7EF's are now that I have a part number!

 

[WicK]

FWIW, I'm happy with NGK TR7-IX (3690) gapped @ 0.030".

Mods include JLT 127mm CF CAI, CFM Twin Jet 67mm TB, VMP 2.4" Upper, 90mm Idler, BPS Oversized & Ported Plenum/Elbow, VMP Triple-Pass Dual-Fan H/E, and Reische 170' Tstat.

Norton, do you get a popping on a cold start? From the cold plug? Then after heating up its good?

 

[Norton]

Norton, do you get a popping on a cold start? From the cold plug? Then after heating up its good?

Negative. No strange noises or behavior.

The car threw a code once, about a year ago, for rich fuel condition. My tuner diagnosed it as stemming from a bad tank of gas. (Note that mods were installed ~3.5 years and 13K miles ago.)

 

[WicK]

Negative. No strange noises or behavior.

The car threw a code once, about a year ago, for rich fuel condition. My tuner diagnosed it as stemming from a bad tank of gas.

K. I might try these out as I get some popping on a cold start, even when I had the tr6s I had this problem. Hopefully they fix it as I didnt have this problem with the stock plugs