I just had my engine rebuilt, and decided to go with a street port. I also decided to put a downpipe in. Do you think I will run lean, or will my stock computer be able to handle the extra flow?

 

You should be OK with only a DP. But when you add a CB and intake you need to be careful, The increased flow capabilities will cause the boost to increase if you have no way to control it. AND we all no that high boost and no fuel leads to very bad things.

 

you have nothing to worry about with your setup right now. if you do decide to add an exhaust system down the line, i would suggest to get a boost controller and keep it at 10 PSI untill you buy an ECU.

but as of right now, you are perfectly fine.