generic 5.0 spark plug gap ?

[85crownHPP]

i was looking at my friends 81 stang today and noticed that the plugs the previous owner put in are gapped at .030 to .035.... every 5.0 Ive worked on has had a gap of .045 or .050....

does anyone know of any reason they should be that closed? The motor is supposed to be an explorer block with edlbrock 289 heads. I dont think the deck has been shaved or anything outrageous that would require a smaller gap for clearance reasons.
As far as I know, a smaller gap is bad for HP - am I right?
I could be wrong.

[gadget73]

I've gapped things smaller on oil burner engines. Helps make a hotter spark so the plug doesn't foul quite as fast, but no reason for it otherwise. It can slightly affect performance. Open the gap up on one plug and see what it does.

[85crownHPP]

aahhh... that could be... a couple of his plugs were indeed oil fouled.
i think that may be a coincidence though, becuase the previous owner came of as a dimwit... on the list of things done to the car he gave my friend was a new 'heater coil'

[Tiggie]

Yuck, 1981 in a 'Stang = 255 V8. The factory spec for it is .050. Takes an ASF42C.

[mrltd]

There could be a heater coil...electric choke....

[85crownHPP]

hhhmmm.... your right. I think he meant core though, becuase they had the dash out.

this mustang was originally a 4cylinder car - the 5.0 was plopped in.

[gadget73]

I don't get why they'd use an Explorer shortblock and 289 heads. The heads are decent and all but you'd have to rebuild them with hardened valve seats to use unleaded fuel. The Explorer heads are probably better anyway, or at least as good plus you don't have to screw with the seats.

[Lincolnmania]

they probably installed the plugs right out of the box............lots of techs dont even bother to gap plugs anymore.......i was once asked why i was doing that at a shop.......i was like wtf?