i didn't see your mods in your profile. i'm running a 75 shot on my b16 without problems at all. there are a few things that you should get (safety reasons) if you plan on running any higher than a 55 shot. higher flowing fuel pump, colder spark plugs, adjust timing on motor. i ran my set up for almost 2 years with a 255lph walbro fuel pump, NGK BKR7E plugs, and 2 degree retard in ignition timing (zex calls for 4 with the 75 shot but after reading the plugs numerous times 2 degrees was plenty). i bought the msd digital 6+ ignition so that when i flipped the n2o switch it would automatically retard timing. that way i wouldn't have to run on the street with less power due to timing retard. the ignition is awesome but not a necessity.