Why would you gap a plug to .28 instead of stock .44 just because you turbo'd your car? Also, the people that tuned it said "you had 4's in there and they're some kind of weird plug so we put in 7's..."

What the expletive does that mean?

And why the hell would you take platinum plugs out and put in copper cores???

... Did I miss the train on this one and get hit by the stupidity wagon instead or . . .?

 

bump.

or is this one just too *** to answer?

 

poot.

 

It takes less voltage to jump a smaller gap and when you're turbo'd, you have a lot more a/f mix in between the plug gap that the spark has to now 'push' through.

A stock D16Y7 uses NGK ZFR5F plugs, which are copper. Don't know why you had 4's in there but 7's are a colder plug and generally used in a turbo setup. Using too hot a plug can lead to pre-ignition and using too cold of a plug can foul it.