I have never seen a set gap. We can get close with the size but all engines are different. I will get some more info and post it. It can be a little large not excessive if this is the case there is another issue. But do not be afraid to turn the idle speed up a little. And yes it is ok to get the idle going and work with the HSN. But keep in mind that you want to get that set as quick as you can or as close to being set. The key to this is to get the engine running on the starter and then get the idle somewhat decent. Not sceaming high. Get the engine warm then run the car on the track. 2 laps fast as you can drive do not wreck the car. Set the needle with these laps 2 at a time slow down in the infield you are working only with the HSN. The work with the LSN after you have to good power. Then when you work with the LSN work with the idle this will also change as you change the LSN. Remember that the engine does not tune like a Nova it runs a little leaner on top and richer on bottom.