Did you get a new kit? They usually come with fairly detailed instructions as to what the fuel pressure and timing requirements are.Normally 6.5 to 7.5 fuel psi .And 2 degrees retard for every 50 HP nitrous with an extra 2 degrees for safety until you have tested it and checked sparkplugs.I have a perf rpm edelbrock kit.On my BBC with the 150HP jets I run 30 degrees total timing and 7.5 psi fuel.Just make sure you have a good fuel pump.I'm still running the stock 3/8 fuel line for the carb and N2O, but I'm thinking of running a small fuel cell for the nitrous and I will use the stock line for that and put in a 1/2 line for the carb.Good luck, the first time you feel the "hit" you will be hooked.