I just hooked up a fuel pressure tester, I started the engine and shut it off, it read about 40 psi. Then after about 15 minutes it dropped to about 30 psi, then it stays at 28-30 psi for over an hour.
So, are they leaking? Or are they okay?

If they are decent I rather stay with them since I really cannot afford to drop extra money on injectors.

Also, I am running 305 injectors on a 350, how bad is this?

 

That leak down rate is normal, the injectors are fine. You may be running a little lean though. 305 injectors are 19lb, 350 injectors are 22lb. The MAF system will try to compensate while in closed loop, but in open loop (when you first start the engine) you will certainly be lean.

40 psi is a little low, should be 44 psi. Did you remove the vacuum line during the measurement?

Install an AFPR and run ~47 psi and you'll be better off than you are now without changing the injectors.

 

funny how you say I could be running lean, because I am running rich as hell.
I think it was due to the MAF relay, I replaced it today and I think it runs better.

 

Hmmm.... I'm not sure what the MAF relay failing would do, but unless you have a modified PROM, I still stand by my previous statements concerning the injectors.

 

Well I would get an intermittent code 33, which is for the MAF voltage low, When the SES would come on the car would run like crap. Backfire, rough idle and what not. So I replaced the relay, light hadnt come back as of yet.