how do you tell wat kinda of injectors you have my friend went to army i took mpfi manifold and injectors he has 10 in jectors at his house 2 i no are 550cc 4 are hf injectors 4 are si stock injectors how do you tell the deferance?

 

hf and si injectors are all 240cc injectors if i am not mistaken. so the 2 550cc injectors should be obvious, and the others are all the same.