injector size
 

I have a 91 z with a 305 tpi. It is bored out .030 with a mild cam, free flowing exhaust, 52 mil throttle body, and a chip. Im planning on replacing the injectors and was wondering if I should get the stock 19# injectors or go for the 22# injectors like the 350. I know the 305 doesn't take as much gas but the computer should be able to compensate for that, and I wouldn't have a problem with running out of fuel at higher rpms. I was planning on putting on an adjustable fuel pressure regulator while I had the plenum apart so I can play with the fuel pressure. Just wondering what you guys thought :)

I would stay with the 19# injectors. From what you stated with your build the 22# one will not help and with the 305 Chip, I would suspect a rich running condition even with adjustable regulator. If you insist, a custom chip will be required.

Lol I haven't decided on anything. I haven't purchased anything and wanted to get your opinion first. I kind of figured that the 22# wouldn't be the way to go but I just wanted to make sure :)

Don't mess with the regulator if it working properly. If you change the fuel pressure, the PCM will adjust the injector pulse to bring the fuel delivery back to normal. It may take a few run cycles for the PCM to negate your pressure adjustment. As for injector size, the same applies. However; if you go too small the PCM will max out the pulse size, but the engine will still starve under load. If you go too large the PCM will make the pulse shorter to reduce delivery, but if the pulse gets too short the injectors will lose delivery accuracy and result in poor idle and drive ability.