my 98 supra tt in need of help

[mandil23]

i have a 1998 supra tt that has been highly modded. The car will not start the car is getting a 50 psi the injectors are not sprayn, ever since i swaped from 850cc to 450 cc. so i have tried to reprogram the aftermarket computer for 450cc injectors but im having problems with that because the car has autroinc computer that flashes a red light then goes off so i thought its not getting power but it test out fine. but when i plug it to my laptop it says short circut in a datalink cable. i bought another serial db9 to usb same problem and my car will not start and i have spent alot i mean alot of money on this car and it dosent run i need help and bad please if you know anything let me know.i will post pics as soon as i can.