ok to start I no allot are gona say why have that setup on a mildly tuned fc turbo, it avoids airbubble in transitions and makes a world of difference

car runs sweet as no problems fitted my bosch 044 and 1.5litre swirl pot rigged up the lines relay etc and now my car idles very lumpy sumtimes revs so slow it cuts out and afrs go richer than ever even on driving afrs are richer than they were before the second pump was rigged in

my question is even with this setup the fpr should regulate the fuel going in, so even if I had 50 fuel pumps the same amount of fuel as standard would be going in due to It being regulated by the fpr

does it mean by me adding another fuel pump that this is high lighting a week fpr ( known to cause fuel leeks and set fire to rx7s) that is cant hold the pressure

no leeks can be seen by eye

any info much appreciated


my setup is perfect bar this issue

 

the stock pressure regulator has a pretty limited range, it cannot handle a big fuel pump, or much boost

 

You had just the stock pump before? Like j9fd3s is saying the stock fpr is limited. Works great when used with stockish pumps but when you try to use a high flow pump they tend to get over run and cant flow enough to properly regulate flow. What does your fuel pressure look like? Remember your fuel pressure regulator is last in the system before it returns to your swirl pot or fuel tank. I would go back to the stock system for the time being until you can properly control your fuel pressure

 

Where is your return line sending the fuel? If directly to the swirl pot, do you have a line that will alloww any overflow to "vent" back into the gas tank? What size line are you running from the new fuel pump vs. The size of your return line? If there is anything restricting flow on the return line, it will cause issues with the pressure side.