how much nitrous will a stock magnum motor take

I'm running a 125 shot (55n/47f) on mine right now and have put about a dozen passes or so on it. I'm at 8 degrees of timing pulled to wind up at 26 total. I thought I was being very safe pulling that much and was surpirsed to see it was about right after reading the plugs.

UOP,how is the response off the bottle,pulled back that much?....