Hi Gavin,
my nitrous controller is a progressive not fixed hit,
so ideally i need the controller to start ramping up to a set gas level, before the vems retards the ignition, otherwise im losing power retarding the ignition before the gas gets going,
this is why (on another post) im trying to find out if vems will accept a trigger input to retard the ignition when the n20 control says its at set % to do so,
i run 150 bhp nitrous and dont need it to retard the ignition until its at about 75bhp of n20,
at present using a cdi ignition unit with built in retard which my nitrous controller triggers at 75bhp and then the ignition retards 6degrees, i cant let the vems control my nitrous pulsoids other wise i loose the warranty, (parts failure and engine damage)
hope this throws some light onto the probs im having.