I believe most nitrous manufacturers feel 150 is safe based on what they have learned from all the V8 motors. Since there is an abundance of fbodies and vettes running around using 150, for the most part, reliably, they feel the same holds true for the Viper with hypercrap pistons.
But maybe the motor will hold more safely. We are working with more volume so maybe a 200 shot would be safe or a 250. I know there are several vettes running 250 shots all day long and other blowing up on 150, so go figure. It is a gamble either way, but that is why I have an extra set of pistons waiting to be installed if need be. But honestly, if it is tuned good than spray away and let us know where the limit is.
Nice mph PJ.