I will be converting from TBI to Carb. I am going to run a 1406 Edelbrock carb, and rpm intake with the center holes machined to work on my 87+ heads, with a vacumn advance distributor from jegs.. I read the tech article on this and have a question about the 3 port regulator suggested.. my question is why?? why do i need to get a three port?? I know i have 3 lines coming to the engine bay, one for the vapor canister that i have already removed and plugged the line.. another is your main feed to the TB unit and the third line is a return line running out of your TB to your fuel tank.. So why couldnt I just get rid of the return line and plug it close to the tank and simply install a single inlet/outlet regulator before the carb.. I know i would only need like 3-4psi of pressure at the carb so a regulator of some sort would be required.. but the 3 port is much more expensive than a single in/out style.. can someone explain to me if there would be any down falls to not running the 3 port and simply blocking the return line..
Thanks in advance

 

you need the return to bleed off excess fuel or to eliminate over pressure condition.

 

And that in tank pump would burn out in no time. It wasn't meant to be dead headed.