Nitrous on a 340 100 shot

The reason you pull timing when on the spray is because the fuel charge is more dense and doesn’t need as much lead (time) to ignite. It’s not just as simple as pull X number of degrees for 100 shot. It takes testing and finding the value that makes the engine happy. Start low, pull 2 degrees per 50 shot, then read the plugs. Evaluate and retest. You’ll find a number where it makes the best power (mph). It will be less than your NA tune up.
Thanks for the info i appreciate all the help, I followed the basic steps and recommendations from the kit and from helpful guys on here. I'll do some pulls again soon and check the plugs quickly after the hit to verify the correct timing and heat range. Unfortunately for me here on vancouver island, our historic race track was torn down for condos and a movie sound stage(last year was the final season) so I won't be able to get ET's or Mph data.... so I'm mostly going to be messing around on the street and hoping to beat my buddies on cruises. But there is tracks a bit farther away I can go race and test at to really get things dialed in later this year. Gotta hate how many tracks are dissapearing!!!!!! Good family fun gone by the wayside