Can I do this?

pistoleye - there is absolutely no problem in putting in the 24s if you put in the matching MAF, although i do agree that it is not needed yet and therefore i would just wait untill you do the other work instead of taking it down twice. the fuel pressure should be left stock.

afastgts95 - yes. you need to have a matcing MAF or a tuner/tweecer to compensate for it. the maf is what gives the voltage curve for the certain injectors. the 24s have to be open a shorter amount of time than the 19s but the computer is still telling it to stay open for the 19s duty cycle.

also, how so does he say they are bad? did they get used and then sit on the shelf for 2 years. in this case they may have gotten gummed up with fuel but that should be cleanable. if they sat new, then there is no reason why they should be bad.
 
They sat used. I really cant even drive the car around right know that is how bad it is running. It barely accelerated enough to get home.The mass air meter is what is causing this then. Sorry if I am kinda of slow on understanding.
 
yeah, you have to change the MAF
if you think you want to, you might consider running a bottle of injector cleaner throught next tank to for the sake of them sitting. thats up to you though. you could wait to see what it does after the MAF.