New to Nitrous

Hi, ran a Big Shot plate system back in 1990. on a 10.1 440-6 bottom end. Ran a seperate 1/2" line and blue race pump for N20 fuel alone (important), 5psi, as low as 4psi on 125hp jets. with 98 octane fuel (4 star UK pump at the time), timing 38 total, NGK B7S's, hit it off the line with 175hp jets, ran good no problems, never tipped a plug, 175 jets gave 8/10ths on my set up. They say retard ignition but its all relevant to your CR and fuel you use and the amount of N20 you put in.