i know this question has been asked 100's of times with 1000's of responses but now ive gotta ask again...im converting over to carb from tpi and am trying to use stock intank pump...ive got the Mallory 4309 regulator but cant get the pressure to turn down...ive tried bigger return lines cause ive read that the return is restricted and causing to much pressure... since that didnt work i tried an inline pump cause ive read that an inline pump will be able to pull fuel thru the intank pump with no issues and that didnt work....it was just a cheapy from advance so i wasnt expecting mericals but was expecting something...my question is now is the cheap inline pump just simply not strong enough to pull thru the stock intank pump or am i doing something wrong with trying to use the stock intank pump....

 

The stock in-tank pump should work fine with the Mallory regulator. You've either got a bad regulator or your return line is restricted. Stock feed and returns lines are adequate size not just for a stock pump but also for a much higher flowing Walbro 255 (which I've used personally multiple times).