Though I'm not a turbo expert I only know the theory, but if I were you, I would stay with the twin setup. You have everything ready (OK, the amount of necessary parts are double), and theoretically speaking (and maybe in practice, the experts may confirm, may not) with two smalles turbos you get smoother curves, better low end torque. What is your opinion?
Or at least the setup now is symmetrical.
'The GTV': '83 GTV6; (summer)
' Mr Brown': '82 Alfetta 2000L; (family car)
'The Little Red': '79 Alfasud 1.3 Super; (under restoration)
I theory and in practice you are pretty much right , but the disadvantage of 2X everything still exists and the engine bay is very crowded with turbo parts (oil lines , air lines , exhausts etc).
The new age pefrormance big single turbos do offer a settlement as they spool very fast and can punch large power at very low relative boost, in the meanwhile I'm enjoying the twins .
I hope I will have new pictures and vids soon , I enlarged the exhaust system once more and 1.1 bar at 3500-4000 rpm was easily achieved at the same ecu turbo's-selonoid duty cycle(imno just by releasing some extra back pressure as AndrewB suggested I gained around 0.4 bar of boost without any other changes, not to the westgates nor the ECU....).
Very carefull fueling must be attained so I did lower the boost now in a respond to the exhaust gains untill new tuning will be applied.
That is WILD You've got to love those times when you are first at a red light and a, pick one (Mustang, 911, BMW, Big Ass Chevy Truck, Ricer) comes up from behind and decides to pull to the lane next to you rather than just drop in behind you...
Looks like it could require constant attention though?
This car belonged to a freind of mine.
the car was sold, and all its components are going to be installed in an 1983 GTV4
but the set up is going to be twin turbos with pair of GT28 turbos.
French cars are shit and shit expensive to service and bloody awful and unreliable and expensive and friends don't let friends drive french cars and you wait years for parts.
GT28s come in almost any size you could want to deal with!
The factory released internal gated Nissan 2.0 GT28s run out of useful boost at about 18psi, and there were "400hp" out of the box GT28s being released a few years back (internal gate)
Over here you can get external gated GT28s that push out to about 500hp worth of air at up to 28psi (ish), but these are custom build jobbies, with different housings and wheels. My mate's
Tight exhaust housings with the right wheel would be nuts on a 24vTT!
) at work....ma-hooo-sive turbo 
You've got to love those times when you are first at a red light and a, pick one (Mustang, 911, BMW, Big Ass Chevy Truck, Ricer) comes up from behind and decides to pull to the lane next to you rather than just drop in behind you...
"Note nissan did not recieve a capital N, for this is an Alfa site! 
"Of course capital on Alfa!") 
"Anyone is welcome to help me out here!?"
