That's why on my wet systems I never used a purge valve, that slight hesitation in the nitrous always gave the fuel a head start...
It may hurt the ET slightly, but I'd rather be safe than sorry.

 

I was thinking the same thing about not using a purge. But what about on a stick car where the nitrous is shut off for each gear change? Is there still gonna be lean spike at each shift?

I think the lean spike is what causes some nitrous systems to hit harder. It momentarily leans out the afr for more power.

 

On a manual trans car just do what I said in my previuos post.