has anyone tryed bigger injectors in there 300 to get more power if it would work

not without modifying the air supply, to get more air. ie: turbo etc. If you just put more petrol the car will run over rich and actually get slower not faster

You have to do modifications to engine itself, but that may cost you extra money...
Did You try chip-tuning instead of replacing injection ?

how do you chip tune the le fuel injection

I think the same way as modern cars....I'm not into chip tuning myself, but you can go in some services which do that..

You can tune the engine by increasing or decreasing the gas flow through the injection, reducing the way of cylinder as well as the size of the cylinder to gain more rpm(s)...just like the sports car...
You might do some changes carburetor.

Just like Pettaw said You have to install turbo or something like that.

Chip tuning an NA is pretty pointless apart from in a few specific cases (usually where a very modern engine has been software de-tuned for emissions/tax purposes. You gain very little for a relatively large outlay. Chipping a turbo car is a different matter, of course.

Adding larger injectors alone is only going to send your AFRs miles off, and lose you power. If you're running out of fuel then larger injectors are the order of the day, but simply slapping them in on a 'dumb' fuel system is only going to end in tears.

cheers

James

The 360 runs rich to start off with.

If you are after more power look at exhaust - head mods etc for power.

The standard head seems to flow pretty well - I'd say intake and exhaust are your first ports of call.

cheers

James