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Discussion Starter #1
Gents,

First off the car is a '94 Automatic BPU.

I just changed my spark plugs from the stock Densos to NGK 3330 gapped at .32. The car runs smoother and idles better.

First gear is more aggressive than before. However, prior to the change, when the car shifted from 1st to 2nd gear it always had enough of a boost to lose traction for a second or so. Now the shift seems pretty tame and there is no huge boost at the shift like there was before.

Any thoughts? Ideas?

Thanks,

Adam
 
Z

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Discussion Starter #2
smaller gap = less power.
your car should idle worse with NGK plugs than with stock Denso plugs. it takes longer to warm up and the car will feel rough.
 

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I CAN HAS WELFARE
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I put my 330's in and gapped them at .028 and it runs good like that. But at idle it misses every once in a while what would be the reason for that?
 
Z

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Discussion Starter #4
not sure, but if you need to gap your plug all the way down to 28 to prevent miss, you probably have a very weak ignition. you should try to replace the ignition coil packs. I ran stock plugs before with new coil pakcs without any problems at hi boost.
at that small gap, the spark is really smashed and I guess would effect preformance. It would also change the air/fuel ratio somwhow thats what I heard. you want to stay as close to stock gap as possible and use 1 degree colder plug to prevent detonation.
 
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Discussion Starter #5
I just went through this myself. Originally my NGK 3330 were gapped at .028, and this caused a very rough idle with missing..

I regapped them this weekend at .035 and that completely fixed the idle-missing problem, and the car seems to run much smoother and more powerful. I'm not sure what the stock gap is (I've heard .044?) but .035 is the most common recommendation I heard here and on mkiv.com.

paulb
 
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Discussion Starter #6
Reed said:
Gents,

First off the car is a '94 Automatic BPU.

I just changed my spark plugs from the stock Densos to NGK 3330 gapped at .32. The car runs smoother and idles better.

First gear is more aggressive than before. However, prior to the change, when the car shifted from 1st to 2nd gear it always had enough of a boost to lose traction for a second or so. Now the shift seems pretty tame and there is no huge boost at the shift like there was before.

Any thoughts? Ideas?

Thanks,

Adam

I have no idea, I've always ran the 6097's which i find to be the best. With gapping of .32 (pre-gapped).

2 RIP
 
R

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Discussion Starter #7
Just out of curiosity........

Why does everyone recommend these if they have less power than stock????

Thanks,

Adam
 
Z

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Discussion Starter #8
2 situations:
some supra have weak ignition, so they miss at high end when they dial up boost. thats why they need smaller gap on their plug so the spark dont need to travel as far.
another reason to get those NGK plugs is its 1 degree colder than stock. NGK rule is 75-100HP gain you need to go 1 degree colder to prevent pre-ignition/over heating the plugs.
if you are running stock boost, just stay stock plugs. if you start missing, get new coil packs. if you start boosting hard, get colder plugs.

Jonas
 
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