spark plug ?

[TwinyTwin]

Just got some NGK 3 step colder plugs and was wondeing what I should set the gap at? Any info is appreciated.

 

[Royal-T-Ltd]

I usually gap at a tight .032. HTH

 

[ijames]

The gap is pretty independent of heat range. Main question is how much boost/timing are you running. Less than 20 psi and low timing (18-20 deg) and the stock gap of 0.035" works okay. Mid 20's and 20-24 deg of timing and I'd go to 0.033 or so, and past that go down to 0.032 or a "tight" 0.032". The bigger the gap the bigger the spark and the better the mix is ignited (and probably the better the gas mileage ), but too much gap with high cylinder pressure and the voltage isn't enough to make a spark and you get a misfire. I run about 21 psi on 93 octane, no alky, and run about 0.033-0.034" with no apparent problems with ac delco rc43ts, rc42t, and ngk UR5's.

 

[QUIP'6']

The gap is pretty independent of heat range. Main question is how much boost/timing are you running. Less than 20 psi and low timing (18-20 deg) and the stock gap of 0.035" works okay. Mid 20's and 20-24 deg of timing and I'd go to 0.033 or so, and past that go down to 0.032 or a "tight" 0.032". The bigger the gap the bigger the spark and the better the mix is ignited (and probably the better the gas mileage ), but too much gap with high cylinder pressure and the voltage isn't enough to make a spark and you get a misfire. I run about 21 psi on 93 octane, no alky, and run about 0.033-0.034" with no apparent problems with ac delco rc43ts, rc42t, and ngk UR5's.

how do u run 21 psi on just pump gas

 

[Royal-T-Ltd]

ALCOHOL! but i dont know what his secret is.... maybe a fmic and ported aluminum heads

 

[ijames]

Stock longblock, cas v2, 20 deg timing at wot in all gears, about 22 psi in 1/2 and 21 in 3rd, limit gt67 p trim turbo (had basically the same results with my old pte54), thdp, atr headers (which probably hurt spoolup as much as they may help top end at my hp level), and 72 lb/hr injectors (no, I don't need that much, they run about 70% dc at 39 psi fuel pressure but I needed to make chips for them for faster friends ), and lots of tuning. I race with what I drive on, Exxon 93, cause I'm cheap and lazy. Best of 12.02/110.87 on drag radials (a 1.95 is a great 60' for me) one cool evening, and 12.20/111.8 on a warmer afternoon after some more tuning with my lm-1 wideband o2. Was making more power but just couldn't get a launch. I put in a little 104 unleaded and added a little timing and 1-2 psi and got my first 11's, 11.95 and 11.97 at 113.3 that same afternoon. That is at a "race" weight of 4060 lbs going down the track, by the way (weighed three times at two tracks over the last four years and got 4015, 4040, and 4060 lbs with varying amounts of gas in the tank and junk in the trunk, but I guarantee that on that last afternoon the total was more like 4080 lbs). It's all in the tuning - you don't want to know how many chips I've burnt over the last 8 years. I have a Yank 10" converter that did help the 60' but cut the midrange some so the mph really didn't change when I installed it, and I blow through a lt1 3" maf but while that helped spoolup a little it didn't change the boost I could run before knock or the performance at the track. I also run a power plate but again, I turned the boost up to just get a couple of degrees of retard, put the plate on, and still had the same retard so I didn't see any improvement that afternoon. I left it on just in case . I've posted this several times here and used to say I was running 22-23 psi in 3rd gear but then I found out my boost gauge was about 2 psi high so now I know I really run about 21 psi in 3rd gear with zero retard as my goal (and usual achievement) on every pass.

I know this is too long already, but the big keys are the fairly big efficient turbo and the frontmount, plus the tuning.

 

[QUIP'6']

Stock longblock, cas v2, 20 deg timing at wot in all gears, about 22 psi in 1/2 and 21 in 3rd, limit gt67 p trim turbo (had basically the same results with my old pte54), thdp, atr headers (which probably hurt spoolup as much as they may help top end at my hp level), and 72 lb/hr injectors (no, I don't need that much, they run about 70% dc at 39 psi fuel pressure but I needed to make chips for them for faster friends ), and lots of tuning. I race with what I drive on, Exxon 93, cause I'm cheap and lazy. Best of 12.02/110.87 on drag radials (a 1.95 is a great 60' for me) one cool evening, and 12.20/111.8 on a warmer afternoon after some more tuning with my lm-1 wideband o2. Was making more power but just couldn't get a launch. I put in a little 104 unleaded and added a little timing and 1-2 psi and got my first 11's, 11.95 and 11.97 at 113.3 that same afternoon. That is at a "race" weight of 4060 lbs going down the track, by the way (weighed three times at two tracks over the last four years and got 4015, 4040, and 4060 lbs with varying amounts of gas in the tank and junk in the trunk, but I guarantee that on that last afternoon the total was more like 4080 lbs). It's all in the tuning - you don't want to know how many chips I've burnt over the last 8 years. I have a Yank 10" converter that did help the 60' but cut the midrange some so the mph really didn't change when I installed it, and I blow through a lt1 3" maf but while that helped spoolup a little it didn't change the boost I could run before knock or the performance at the track. I also run a power plate but again, I turned the boost up to just get a couple of degrees of retard, put the plate on, and still had the same retard so I didn't see any improvement that afternoon. I left it on just in case . I've posted this several times here and used to say I was running 22-23 psi in 3rd gear but then I found out my boost gauge was about 2 psi high so now I know I really run about 21 psi in 3rd gear with zero retard as my goal (and usual achievement) on every pass.

I know this is too long already, but the big keys are the fairly big efficient turbo and the frontmount, plus the tuning.

THANKS