spark plug gap

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spark plug gap

Postby DroptopDrifting » Sun Oct 07, 2007 10:13 pm

ok, i believe my stock gapping was 38? i see some people have gapped the BKR7E plugs to 26. im getting ready to go turbo and i was wondering, what should i hap the plugs to. i have stock internals, just rebuilt my timing though with the ams performance timing rebuild. i'll be running a t3/t4 50 trim, turbo manifold to 3" downpipe to 2.5" straight pipe, muffler 2.5" in 3" out, 38mm wastegate, BOV, FMIC, walbro HP 255lph pump, 550cc injectors, adjustable fuel pressure regulator, z32 tt fuel filter, msd SCI-L ignition, blaster 2 coil pack, and im sure im forgetting something small. i'll be using an enthalpy tuned ecu, with a safcII and zeitronix wideband for fine tuning.

basically the only question i have is what gap should the plugs be at lol. the rest of it i got down pretty good.


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Re: spark plug gap (DroptopDrifting)

Postby s14det » Mon Oct 08, 2007 1:12 pm

I would say sell the MSD SCI-L ignition and get the Kennebell Boost-A-Spark. Then you can run .05+ gap on the plugs. I run .06 gap up to 18psi and runs awesome. Drives/Boost so much better with the bigger plug gap.

Most people run there gaps at .035 or so or lower to .025 depending if you get spark blow out or not at your boost lvl. Bigger the gap the more it is able to ignite the fuel (more power and more efficent)

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Postby Florida240sx » Mon Oct 08, 2007 7:27 pm

I run .031

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Postby mtmetzger » Tue Oct 09, 2007 4:45 am

Mine is set for .029

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Postby WDRacing » Tue Oct 09, 2007 8:54 am

To actually answer your question, the best GAP will vary for everyone. However, you want to run the biggest gap possible until you get spark blow out on boost. The reason being that the larger the gap, the bigger the spark will be. More spark equals a better burn and even better emissions.

So I recommend starting at .035 and closing the gap until you find a happy medium. In closing, .035 is the answer.

Also use colder plugs by 1 or 2 heat ranges.


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Re: (WDRacing)

Postby S13FX » Tue Oct 09, 2007 9:43 am

BKR7E's for the win. Just make sure you get the ones with out the - 11 in the end, cause that means their pre-gapped already, and it ****s it up when you try to correct the gap.

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Postby Jookmasta » Tue Oct 09, 2007 11:47 am

.24 for me.............17 psi tho............

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Postby frosti108 » Tue Oct 09, 2007 11:54 am

im leaving my bkr6e's at about the .028 they came gapped at. when i get my msd components ill get bkr7es and gap em like i do my gf's pooper

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Re: (WDRacing)

Postby CRESCENDO » Tue Oct 23, 2007 4:12 pm

And if I feel hesitation/misfire at high RPM/high load?

Just checked my gaps - all at .27

Simple rundown:S15 SRFMIC, Int, Exh, DP10psi

The reason for my question is that I don't feel the hesitation/misfire at 1/2 or 3/4 throttle on boost...only at pretty much WOT high RPM's. Any clue?

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Postby eazye2000 » Tue Oct 23, 2007 5:15 pm

I'm running a 35 gap on mine. And boosting 18psi. I also have a Blaster SS coild. Dunno if that helps. I also have Nology 10.something mm plug wires, but only a 7mm coil wire.. lolDon't ask me how it works, but it works. You will find a happy medium. It might just take a bit of time. Like WD said, it's different for everyeone.

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Re: spark plug gap

Postby Marquez » Fri Dec 06, 2019 6:43 am

Hey guys!so i have a 91 240 and i would like to have a few pointers on what gaping should i run on it with the following! Ka24de ! Msd 2 blaster no resistance added, magnacore r-100 ! It seems like i can get it running right for a couple of hours then it starts to misfire! Also i checked all vacuum hose and replaced the ones that were bad it fix a lot of symptoms but not everything! I started playing with the air/fuel mix pump and also can’t get it right it’s either to rich and has this strong smell of un burn fuel. Or to lean and doesn’t get much rpm’s ! I need some help also i should mention that the egr pump it’s been deleted !

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Re: spark plug gap

Postby Marquez » Fri Dec 06, 2019 6:49 am

Sorry droptopdrifting i didn’t mean to take away attention from you post!! I actually a new member here and don’t know where I should have started my question at ! Sorry everyone! My bad !!

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