Forced Induction Custom FI Setup Questions

what to gap plugs at??

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Old 09-15-2004, 11:17 AM
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Default what to gap plugs at??

my car runs great, but up top about 1 or 2k before redline in higher boost, she falls on her face and pops out the exhaust. i'm pretty positive it's my plugs, i still have them gapped at stock .44, what should i gap them at to eliminate this. i've heard before, i think someone said either .38, or .28, can't remember :P hell when it first happened, i was trying to run about 14 psi., and got scared and turned it down to 11, now it's starting to do it at 11 and even 10 psi. so once i regap them, i gonna crank it back up to 13 or 14 psi.
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Old 09-15-2004, 11:53 AM
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Default Re:what to gap plugs at??

is that really the cause of the backfire at hiugh rpm's? i always woundered what did that. i kinda like the sound of it though
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Old 09-15-2004, 11:56 AM
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Default Re:what to gap plugs at??

Originally Posted by crx2fast
is that really the cause of the backfire at hiugh rpm's? i always woundered what did that. i kinda like the sound of it though
this isn't a regular back fire like when shifting gear, this is getting no spark while still in throttle and teh car falling on it's *** and popping until you change gears. it's not very appealing :P
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Old 09-15-2004, 12:04 PM
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Default Re:what to gap plugs at??

nevermind, did a little research and found out my self. most everyone suggests between .25 and .30 gap, but mostly between .28 and .30. found out you experience that lack of spark due to the decrease in timing as the boost goes up, plus a huge gap, basically equals no spark at all, thanks for all the help guys
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Old 09-15-2004, 01:38 PM
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Default Re:what to gap plugs at??

This was happening to me too, I was blowing out spark at higher rpms. Gapped it to .30 and my probs went away.
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Old 09-15-2004, 01:42 PM
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Default Re:what to gap plugs at??

nice, i can't wait to get home today and regap them, i haven't been able to boost over 9 psi without this happening. i was thinking it was due to leaning out, but i have no detonation at all, so i did a little searching and found it's more than likely from the spark blowing out. can't wait to boost 14, too bad it's raining out :P
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Old 09-16-2004, 07:01 AM
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Default Re:what to gap plugs at??

well, i couldn't find my spark plug gapper, so i ran to the auto parts store (advance auto parts) to pick one up, while i was there i decided to go ahead and get one step colder plugs. as many of you know by now, the part number that we have (bkr7e-11) is the ngk part number, not that stores stock number, this is the number on the ngk box, but not the number the store uses to find it in the store. anyways, the store number at advance auto was '1283'. i just here everyone saying how they went to the auto store and asked for 'ngk bkr7e-11' plugs and they look at you like you're stupid. the only way they found it for me was b/c i was persistant and kept telling them it's the same exact part number for my civic but the heat range is '7' instead of '6', they come stock in some turbo model saabs. anyways, just TELL them to cross reference the ngk part number to get their store stock number, make them work, that's what they're there for anyways, i regapped my old plugs to .28 last night since they had to overnight these, i noticed a big difference, i was boosting 12 psi this morning and it felt great all the way to redline, i'll prolly raise it to about 13 or 14 psi. today. anyways, gapping my plugs solved the problem, so if you're boosted and running stock gap, GAP YOUR PLUGS TO .28-.30!!!!!!!!!
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Old 09-16-2004, 07:14 AM
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Default Re:what to gap plugs at??

good.. now make another vid! :P
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Old 09-16-2004, 07:18 AM
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Default Re:what to gap plugs at??

hey projectteg i got an 99'Si b16 t3 /60. when your doing a top end pull in 5th to lets say 125-135mph does your car
start acting funny after that? like the rpms won't go over 2k? mine did this to me twice now and as soon as i turned the car off and turned it back on it went away.
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Old 09-16-2004, 07:30 AM
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Default Re:what to gap plugs at??

Originally Posted by trebor_nordap
hey projectteg i got an 99'Si b16 t3 /60. when your doing a top end pull in 5th to lets say 125-135mph does your car
start acting funny after that? like the rpms won't go over 2k? mine did this to me twice now and as soon as i turned the car off and turned it back on it went away.
no
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