Importance of correct spark plug gap?
I have always gapped my spark plug within the factory specs. I recently changed the spark plugs in my Ranger and after I had removed three from the right side (the tough ones) I realized I left my gapping tool at my shop with my race car. The minimum gap is spec'd at .062" so I decided to use a 1/16" drill bit to gap the plugs. The next day I measured the the drill to make sure it was right and it was .059". I forgot drills are a little under sized.
Now my question is: Is this gap being .003" under the spec really going to have any effect on the engine performance? It is running just fine but I have not gone through enough gas yet to determine if it has effected my gas mileage. Could it possibly effect emissions?
When I put an electronic ignition on my race car it was recommended that I increase the spark plug gap to around .035" or more. When I ran it on the dyno, the results showed that a .025" gap gave better horsepower.
I don't want to change the gap because it is too much trouble but I just wondered if anyone had information that a .059" gap would give me problems.
2002 FX4 Bright Red Supercab 4.0 SOHC, manual 5-spd & Tcase, 33" BFG MTs, K&N air filter, Modified air box inlet, Gibson SS cat. back exhaust, Bama flash, Hidden Hitch round receiver, Rear helper air springs, Electric trailer brake controller, Line-X bed liner, WAAG bar with KC lights and Wildernest shell.
Last edited by IN2 FX4; 11-28-2005 at 02:32 PM.