Smaller Plug Gap vs. Larger..Pros and Cons..?

Hey guys, 95 4.6L v8 tbird with 130k miles...bone stock.

Tomorrow i'm gonna be changing my plugs, my emmisions tag says to gap at .052-.056.....but i've read that a smaller gap is better if you harder on the vehicle..which i am. Something about the gap being smaller makes a stronger spark..? Is that true..?

Generally, whats the differance between a plug gapped at like .054 and one gapped at .044..? I was gonna get motorcraft, but all i could find was autolites, the platinum ones..they are all gapped already at a solid/accurate .044.

Also, should you slightly crimp/or make the plug boottighter so it fits tightly on the plug..? OR, leave it that it basically slips on..?

Provided your ignition system can handle it, the best spark will be over a wider gap. The spark kernel itself will be hotter and of course it will be a larger area. Going too wide will cause erratic spark, cold spark, excessive radio noise, and misfiring. I'd say stick to the manufacturers recommendations. Most GM HEI ignitions recommend .050-.055" I've gone as high as .065 on HEIs with really hot coils.

I'd say stick with your factory settings unless you have access to a tune-up shop with an oscilliscope. I think if you go as small as .044 on your car you might notice a slight drop in power and a few extra HC emissions.

Expanding upon Curtis' response...you need 2 components to make a good spark. a) a good firing voltage and b) a good spark line after it fires. The firing voltage is controlled by the gap, since it is the widest air gap in the system (or better be). The firing line is the duration of the spark. You only get so much voltage as the coil fires. By widening the gap, you use more voltage to fire the plug and thus shorten the duration of the spark. If you shorten the duration too much, you'll have incomplete burns. Too little gap results in poor ignition as Curtis mentioned. You need the scope mentioned to see the difference. Keep in mind that the spark WILL find a path to ground every time. If not across the plug, somewhere prior to it.