The widget in a Guinness injects an extra shot of nitrogen into the beer before it is poured. you won't achieve the Guinness head on a beer unless you invest in a nitrogen set-up for your kegorator. and start to condition your stouts with nitrogen instead of CO2. Your best bet is to find another stout that you like and try to follow that, one that isn't conditioned with nitrogen, unless you have the money to have a nitro set-up.
"Yes, I am a pirate two hundred years too late. The cannons don't thunder there's nothin' to plunder,
I'm an [under] forty victim of fate, Arriving too late, arriving too late."