.43 is the gap
43 thousands of an inch
.43 gap
.43
It's .39 to .43
You don't need a diagram to find spark plugs on this engine. Follow the plug wires and you will find the plugs.
Don't really know because the manual states on 1-43 0.0048 but also states 0.0035
.38-.43 with .40 ideal for idle and highway speeds
Between 40 and 45 on the gap gauge. Start with 40. Try 43 if not happy, then 45. If 40 to 45 does not perform correctly, there is something not right.
If it's electronic ignition the plug gap should be 1.1mm you buy spark plugs already sized (NGK BP5ES-11) It depends on what type of spark plugs you are using. For conventional plugs the gap of 1.0 - 1.1 mm (0.039 to 43") is correct. If you are running Platinum plugs, I like to gap at 0.005" extra (0.44 - 0.048"). I get good performance with NGK 7082 Platinum. Cheers Malcolm
You should have them at 40 to 45 with a gap gauge. Try 40 first. Go 43 next, if you are not happy. Anything over 45 would not be good.
Usually about .035" for points-type distributors and .045" for HEI type. A bigger gap is better, but only if the ignition system can handle it. Also, 45's are a little hot for most performance applications. Try 44's, then 43's, but keep an eye on them for fouling.