Bigger isn't necessarily always better with fuel injectors. You get them too big and at minimum pressures your engine could run entirely too rich. Yeah, you can run low fuel pressure and the computer will shorten the injector pulse to compensate, but now the injectors won't be running at optimum efficiency. Think of the spray from a garden hose with the house valve only cracked compared to the house valve full open. You still get a decent spray, but at the lower pressure the fuel isn't going to be atomizing as well. Trial and error with a wideband O2 sensor would be the best way to get the correct size. I'm sure everybody's got a wideband laying around, right?';
There's an analyzer on here somewhere that helps you get a good idea what size would be appropriate.
Accel also has some very good flow/pressure data on their site at
www.mrgasket.com