Plug gap question

[topless95]

I have a good question, on my 95 5.0 it calls for the plugs to be gapped at .054" , when I changed the plugs they were originally at .035" . Since changing the plugs it feels as if performance has gone down, any ideas? Lastly I am about to put some GT40 x303 heads on next week and I am picking up Motorcraft AGSF-32c plugs, what should I gap them at (On a side note I am also adding a Crane HI6s system, tired of all the unburned fuel coming out of the tail pipe)?

Thanks as always

 

[toyman]

I have a good question, on my 95 5.0 it calls for the plugs to be gapped at .054" , when I changed the plugs they were originally at .035" . Since changing the plugs it feels as if performance has gone down, any ideas? Lastly I am about to put some GT40 x303 heads on next week and I am picking up Motorcraft AGSF-32c plugs, what should I gap them at (On a side note I am also adding a Crane HI6s system, tired of all the unburned fuel coming out of the tail pipe)?

Thanks as always

The gap as noted should be at .054". A .035" gap would generally be right for boosted applications. Not familiar with the plugs you are referring to but experience seems to favor staying with the basic copper core plugs for our engines.

 

[HISSIN50]

Toyman is correct.

The difference in the power feeling is likely from the underlying issue (you mentioned unburned fuel). If this is indeed true, the smaller gap is less likely to foul.

The gap is your call. If things stay the same and 0.035" worked for you before, I'd run 0.050" with a box. The extra juice should mitigate the extra gap.....

Good luck.

 

[revhead347]

They seem to run the best at about .042" .054" is way too big.

Kurt

 

[HISSIN50]

Kurt, without further info, I'd respectfully disagree. A healthy stock TFI ignition on a stockish car (I've not seen him mention anything extraordinary in his combo) should easily handle the 0.056" gap (they can handle more).
Now your combo would be a totally different ball of wax............

 

[Touring23]

Crikey! This question is on every Stang web site on the intranez!

Too small gap=reduction in spark power
Too large gap=increased # misfires and thus reduction in power

Read:
forums.corral.net/forums/showthread.php?p=8145423
Amazon.com: Performance Ignition Systems, Dr. C. Jacobs
Stealth 316 - 3S Spark Plug Information
Autospeed

Then search. The troof is out there.

 

[revhead347]

Kurt, without further info, I'd respectfully disagree. A healthy stock TFI ignition on a stockish car (I've not seen him mention anything extraordinary in his combo) should easily handle the 0.056" gap (they can handle more).
Now your combo would be a totally different ball of wax............

I've found that stock gap works, but taking it down just a little helps the car run smoother and make more power.

Kurt