I would agree with silver92b.

If you are using a piggyback, the best injector is a 305cc injector from the Supra.
The 1.6 cannot idle anything larger than that I believe.

Since you are using MS, I would say go with the 326cc gray ones from a 626 or B2000.
They are plug and play.

Next step would be RX7 injectors, 440cc-460cc, good for at least 230-250whp. Easy to find.

 

this thread is awesome it gives me a great idea of what kind of power i will be looking at

 

It all depends on the car and the setup. No 2 supercharged (1.6) cars are the same. There are some that make 165 whp and others that make 140 whp. The superchargers do work to make more power than a stock N/A motor, but I think they are limited in power making potential. There are just too many more options in blowers for turbochargers.

In reality, the turbos make more power easier than the roots blowers. Still, I have a M45 Eaton blower and I'm going to stick with it for a while. If I had money to burn, I'd try a nice turbo set up, but hey! I have the SC already.
Any more mods I do can be used with a future turbocharger set up. For instance, an ECU upgrade or injectors upgrade can be used on a turbo. Also, a water injection system can be used with a turbo.

It all depends on what you want and what you can afford. Maybe you run into a killer deal on a used SC. Then why not? It sure is nice to increase your HP and TQ by nearly 50%! That is what a typical M45 SC will do for your typical 1.6 engine. That's with stock injectors and with a primitive, old school fuel & ignition patch. An AFPR and a boost retard control is all you need. Just tune it and adjust your base timing and fuel pressure for safe operation and away you go.