Spark Plug Gaps
#3
RE: Spark Plug Gaps
Most of the gains from the larger gap are going to be in the 1500-3500 rpm range where the factory spec ignition timing is heavily retarded so that a 9:1 compression ratio engine can run on low octane fuel.
The gain might be 5 ft-lbs on a 340-375 ft-lb of torque engine.
I believe that you can go as large as 0.060 inches of gap on a conventional plug if you are willing to resharpen the plug electrode edges every 5,000 miles.
If you don't want to resharpen so often
you can buy some of the $6 to $12
iridium tipped sparkplugs
where the alloy of the tip is much more durable.
The gain might be 5 ft-lbs on a 340-375 ft-lb of torque engine.
I believe that you can go as large as 0.060 inches of gap on a conventional plug if you are willing to resharpen the plug electrode edges every 5,000 miles.
If you don't want to resharpen so often
you can buy some of the $6 to $12
iridium tipped sparkplugs
where the alloy of the tip is much more durable.