320 Lph In Tank Fuel Pump And Stock Regulator? Excessive Flooding?

Mar 30, 2005
602
0
17
34
mtn home arkansas
Hey guys I added a 320 LPH pump to my 97 cobra for my vortech setup and this car is flooding out horribly. My tuner and I datalogged fuel trims and they are within reason. However this car is blowing black smoke severely and barely running. I pulled the plugs and they are carboned up with fuel soak. Could this high volume pump be overrunning the stock FPR?
 
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Mar 30, 2005
602
0
17
34
mtn home arkansas
Alright went out and did some more testing this time not rushed like earlier. After 3 key cycles the pressure shot up to and held about 37 psi. That's a least some decent news I think lol
 

wmburns

SN Certified Technician
Aug 14, 2009
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Houston Texas
Help me out here. This is a return fuel system correct? Why hasn't the fuel pressure been measured/logged then you would know?

The post doesn't state how the 37 PSI measurement was done. Because 37 PSI at idle is too high if measured with an external gauge at idle. At idle there should be a vacuum inside the intake. The fuel pressure should be closer to 32 PSI.

Has the intake vacuum reference line been confirmed connected and leak free?

The other thing that's not correct is the fuel trim values. If the fuel trim values are correct but the spark plugs say rich, that says to me "EXHAUST" leak or the PCM closed loop processing is not working.
 
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