318 Motor, please help

FOR THE WIN!!!! I just got home, practically ran my wife over to head out to the garage and try this out. i pulled off the breather with the hose attached, crewed on a basic oil cap for now and plugged the hole on the back of the carb. fired it up, dropped it into gear without even letting it warm up and it stayed running!!! now i know there has been a vacuum leak this whole time so all my tweaking has been for not. now i can start all over and get this bad boy running strong. i cant believe i didn't think of this. i'll be going to NAPA tomorrow for a PVC valve. Thank you Bobzilla!!! Thank you everyone else for the help, ill keep you posted. and no.....i wont get rid of my Holley, i think they look 10x better than the Edelbrock and much more tunability.

Get a vacuum gauge if you don’t have one. Hook it to manifold vacuum and take it for a drive.

Look at your CRUISE vacuum. Whatever that number is, let’s say 15 inches you’ll need a 10.5 power valve. That’s where I would start.

Of course, this depends on your emulsion stack and main air bleed sizing but you can’t get anything that opens sooner than 10.5 inches.

If you are making a lot of power the quicker opening power valve may be the best option. If you’re not making a ton of power you may be able to open the power valve later without causing a stumble.