Im just wondering what heat range (2 or 1 colder than stock)
are people running with their #5 pulleys?

Even if you are running better gas is there problems with fouling plugs on the street with the 2 heat ranges colder?

I need to know I might finally put my chip and pulley on Wedsday.

I have a custom JL chip for 91 octane he said it made 380 rwhp
and 480 rwtq with the #5 pulley.

Im also considering having Danny Swanson do a custom Dyno tune and hes suggesting the 2 heat ranges colder.

What do you guys think?

Ronnie 2001 black and stock
13.66@102.77 , 2.2 60 ft and 70 deg at Carlsbad
best mph 103.05

 

I run the NGK BR7EFs(.040) with my 5 lb pulley. They are 'chilly'! They misfire at idle(you can hear the 'pop-pop--popopop' coming from the exhaust tips) and low rpms but clear right up as you get into the throttle. If I had it to do all over again(and I will in another 10,000 miles or so), I think I will go with the Denso IT20s.

Every truck eng. is different and yours might not misfire--as much or you might be OK with NGK TR6s?

Dan

 

Go with the Denso IT20's...

 

Use tha' Denso's, foo'

 

Ronnie, I run the TR 5 gapped down to .038 so there not quiet as hot as the would be at .045, and Im running the 6# pulley. If you try these and have any detonation issues you will just have to go to the TR 6. Have you seen this post about plugs. The hotter the plug number the better as long as your not causeing detonation or preignition. Here check it out.
http://www.centuryperformance.com/spark.htm