iam now looking to get a good 300low boost 400hiboost turbo....will a t3/t4 60trim be good.............and will the 750cc injector hold up to that much.....

 

That turbo will work just fine for your goals. A 57trim will work as well. The injectors are also fine for your power goals. If you want to figure out the sizing for your exact goals, use 6cc per whp to figure it out

750cc x 4inj = 3000cc total
1500cc / 6cc (per whp) = 500whp with a safe injector duty cycle