if they didnt leak when you primed it you will be fine. i had a problem with my injectors after switching to a car style injector and when it wasnt seated right it let me know buy spraying a crap ton of fuel everywhere ... lol

Like previous said. Each style of intake takes a certain color orings.

Figured I'd update this for anyone else who searched, the O rings that come with the injectors work fine, no leaks at all