Retarding timing and which plugs to go with

Will retarding the timing really be necessary for a 75-125 shot? I have a pcmforless tune with probably a few more degrees of timing than stock and I will be running a colder plug. The reason I would like to know is because I can get a good deal on a BMN window switch and use that. Or I can buy a Mallory Hyfire ignition for 240 bucks just to have a revlimiter and timing retard abilities for the nitrous. Also, what plug do you guys recommend? BTW, we only have 91 octane in AZ. I can get a hold of 103 octane if I need to when I go to the track.

Generally it will not be necessary to retard timing for a 125 shot. However if the PCMforless tune is on the regged edge for max timing you may want a few degrees. Maybe you can ask him what the max timing was on your tune.

If you are worried you could probably just add 2-3 gallons of 103 unleaded. That would definately give you the room to spray the 125 or 150 shot.