Spark plug gap on 302

[V8GrandMarquis]

Hey guys just got tons of goodies for my Merc just wanted to know what gap should the plugs be thanks

[gadget73]

.052 sounds right. Its on the fan shroud emissions label.

[visionmercury]

yeah stock is about .052 ive got mine gapped at .035 if i remember right

[gadget73]

thats like way small. Might wanna open that up a bit for optimal flame front.

[visionmercury]

ive played with the gap on my car for a few yrs and that works great and it runs wonderful for me !!

[gadget73]

just been my experience that running the gap too small costs some power. If it runs better with a smaller gap, usually the ignition system is too weak to handle the compression of the motor. On a dead stock lopo, thats like 8.5:1 or something. If it can't fire across that, something is severely wrong.

[visionmercury]

its not dead stock , i pulled the plugs out this morning to change them and they are gapped at .042 ,i have a ful msd set up on the car i know its not week at all , it runs strong .

[gadget73]

dead stock meaning engine internals. Stock heads, pistons, etc.

[visionmercury]

yeah all i have is a cam and 1.7 roller rockers , so yeah i would fall under that !!!

[visionmercury]

i saw it n my ngk catalog . so i went to there site and copyed it. a larger gap isnt better

FAQs - Spark Plugs
Q: How do I "read" a spark plug?
A: Being able to "read" a spark plug can be a valuable tuning aid. By examining the insulator firing nose color, an experienced engine tuner can determine a great deal about the engine's overall operating condition.
In general, a light tan/gray color tells you that the spark plug is operating at optimum temperature and that the engine is in good condition. Dark coloring, such as heavy black wet or dry deposits can indicate an overly-rich condition, too cold a heat range spark plug, a possible vacuum leak, low compression, overly retarded timing or too large a plug gap.
If the deposits are wet, it can be an indication of a breached head gasket, poor oil control from ring or valvetrain problems or an extremely rich condition - depending on the nature of the liquid present at the firing tip.
Signs of fouling or excessive heat must be traced quickly to prevent further deterioration of performance and possible engine damage.

[1990LTD]

On a dead stock lopo, thats like 8.5:1 or something. If it

[1980c10]

You generally would like to run as large of a gap as possible without blowing out the spark or the arc not being able to make it. This will give you a larger spark and a larger flame front, resulting in a more complete burn and a more effecient engine.

[91waggin]

You generally would like to run as large of a gap as possible without blowing out the spark or the arc not being able to make it. This will give you a larger spark and a larger flame front, resulting in a more complete burn and a more effecient engine.

This. Bigger spark means more complete combustion.