Tight idea
 

I thought of this as an alternative to NOS.
Say you have 720cc injectors in your car, if there was a way you could press a switch where they would only inject 555cc then, when you really wanted to smoke somebody you could just hit the switch, and BOOM! you would be at 720cc
I bet this could be possible, but would take somebody who is good with electronic,(not me).

It would be possible.... sort of.

You forget that you've probably got an engine management computer that you'd have to work around. It wants to give you fuel economy, and smooth ride. You want maximum perfomance. Guess who has the final say?

You would end up having to heavily modify some part of your intake since you're obviously going to have to add AIR along with the fuel. Just dumping more fuel into the chambers will make it bog and run slower. You've got to figure out a way to get a metered amount of air into it at the same time the fuel hits, so you can keep it around the stochiometric ratio thing where it will produce the most power. Major electronics / engineering / fabrication headache! Possible though.

If you were running some kind of blower, or a carb; life is much easier. You can modify the setup of your turbo(s) a bit, set up an OD transmition type thing for the drive pulley of a super, or install a dual carb intake manifold with common plenum with one carb set up switchable.