Spark Plug Gap?

[82ndCowboy]

I searched the forum for "spark plug gap" and it came up with 104 threads. But none actually discussed what everyone's thoughts are on setting the gap.
So I thought I'd throw this out there?

I know the manual says the gap is supposed to be 0.8 to 0.9
And when you buy the NGK spark plug the -9 means it's supposed to already be set at 0.9
But has anyone played around with the gap and found which is better, 0.8 or 0.9
I always check the gap on new plugs just to make sure they are set right. And even though it supposed to be 0.9 all 4 were at 0.8 on the last 4 I bought.
So I decided to split the difference in the manual and set them all at 0.85

So what are your opinions on spark plug gaps?

 

[richwrench]

I always gap mine to the minimum spec because as the electrode burns down the gap will naturally increase. It's been my experience that most vehicle run well when gapped at about .035". The wider gaps that some manufacturers call for (like .055" on my F150) can cause mis-fires under certain conditions. I haven't played around too much with the gap on my 'Max - I can't imagine going too much wider or narrower from the spec is going to improve performance, but then again I'm not a racer & I've never dynoed at different gaps.

 

[Jayhawk]

I have always preferred increasing the gap slightly:

 

[vmaxride06]

Thats a perfect Gap Jayhawk:biglaugh:.
I set my gap to .35 on my new plugs and all is well. Runs snotty. The old plugs with 5500 miles on them, when cold checked .35 to .36.

Chris Hansen

 

[Dreamster66]

Thats a perfect Gap Jayhawk:biglaugh:.
I set my gap to .35 on my new plugs and all is well. Runs snotty. The old plugs with 5500 miles on them, when cold checked .35 to .36.

Chris Hansen

yea, nice gap (e) but dont get sand on it like Jayhawk did!

 

[lankeeyankee]

I am running 1size colder NGK plug gapped at .32 I dont mess with crap if I am not having any issues. If I am not getting misfires or detanation than I really dont see any gain in sparkplug gapping as long as its within reasonable tolerance with factory recommendations.
I believe if your pouring large amounts of NOS, or alot of boost from a turbo than you may want to try different temp plugs and gaps, other than that if your running a stock engine set it to factory.

 

[82ndCowboy]

I have always preferred increasing the gap slightly:

Dammit... Now I'm hungry!