my 67 mustang has a 289 engine and basically stock. it has the pertronix ingition module. i was wondering how wide of a plug gap i should set to increase power. i have been running about a .035 gap (autolite platinums). also, if i increase the plug gap do i need to adjust the timing?
I have a Unilite distributor conversion and gap my plugs at .045. I never have a problem and it also helps the plugs even with two cylinders leaking some oil.