depending on how much boost he was pushing. Mustangs are not like our cars. Stock is 19# injectors. We can just install 36# or whatever size we need and not upgrade the ECU. The only thing we have to do is make sure the mass air meter is calibrated with the injectors. The stock computer can only handle 56# injectors. Anything over that, he would need to get the DFI. That alone is a good chunck of change but even more to find someone to tune it. Like here in Florida, I have only heard of 3 guys that can tune a DFI. Friend of mine has a single turbo on his car. Its the Thumper Turbo. I don't know what the highest HP rating it is, but so far he ran a 7.21@193.8