I am new to the engine scene. Ive done a good amount of work on engines but i still have questions. What does the lbs and the flow rate mean for a fuel injector. Also i was looking to put a 383 in my 86 Iroc when i return from Iraq. What should i use for an engine like that. Thanks.

It's the amount of fuel that would pass through the injector in an hour, if the injector was open the whole time. The rating is at a given fuel pressure though, increasing fuel pressure also increases flow. Most domestic car injectors are measured in lbs/hour, but others (mostly import) ones are measured in cc/minute. You can convert between the two fairly easily, there are online calculators out there that do it for you. As far as what injectors would be best for you, I can't say for sure. It really comes down to how much air is going into the engine, because you need to match that air with fuel. Stock ones for a 350 are 21lb (I believe, may be 22), so you'll need at least that much. You may be able to get away with stock injectors, but at a higher pressure. You would need an adjustable fuel pressure regulator, but this allows you to adjust the injector flow, across the board.

Alright, I already have K&N filters, and I plan on upgrading the amount of air flow when I drop the new engine in. Thanks for the information, this forum has answered many of my questions.

There are also online calculators for injector size based on estimated, or known horsepower. When I built my 388 I estimated 30 lb injectors because I'm street and not racing, but would have gone larger for racing.