no. The computer actually doesn't care what MAF and injectors you have as long as the MAF is calibrated for the injectors that you have. A stock GT MAF is calibrated for stock 19 lb injectors, so that would cause problems - you'd run rich basically.
If you have an A9L computer, you'd be better off w/ it than a cobra computer. From what I understand, the A9L has better fuel and timing curves and is the favorite computer from stock Mustangs (I know 90-91 5spd 5.0's have them, but not positive the other years).
i was told in other post that the cobra computer was the one who takes care of the inyector and only 24's is that true???????????????????????
right now i have 19's and the car is suck