Dose anyone have a name for a reputable comany who can do this?

 

Which ECU, and what year is it from? If it's the stock ECU from your 91 Si, it should hopefully be a PM6, and hopefully that has the external program on it, so piece of cake. What changes do you need to your program, and what engine are you running?

I'm reputable, but I'm not a company. I'm cheaper than a company though, because the only employee is me. =)