No is the easiest answer. As well as the turbo you would have to uprate the con rods, crank shaft, ECU, fuel pump, fuel lines injectors, fuel rail etc etc etc. it would be easier to drop a turbo engine in and uprate the suspension. I think you might also need to look at the diff too. Maybe just sell you 944 n/a and buy a turbo.
Yes upgrading to a turbo from an n/a will cost you more than selling the n/a and buying a turbo. The gearing in the transmission needs to be changed, the ring and pinion gear also need to be changed (the n/a had a much weaker ring and pinion) The turbo also had a transmission cooler.