LT1-LT4 Modifications 1993-97 Gen II Small Block V8

fuel pressure issues

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Old Dec 15, 2012 | 02:25 AM
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1BadAsZ's Avatar
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From: Florence, MS
Default fuel pressure issues

For some reason my fuel pressure is low, I believe its the reason for the backfiring thru the intake, stumbles, and LOW power. It hangs out around 39-40 psi, and 41 with vacuum off. I have racetronix #32's and racetronix pump. I have a stock regulator. I just put a new filter and the hotwire kit on for the pump today and still no changes. When I give it gas, just easing into it the pressure goes down. I was watching some of the sensor activity on the scanmaster and the map sensor goes down as well when you give it gas. Is that normal map function?
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Old Dec 15, 2012 | 02:56 AM
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popo8's Avatar
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WHat racetronix fp do you have?

Did this happen after any certain upgrade?
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Old Dec 15, 2012 | 03:08 AM
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1BadAsZ's Avatar
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Launching!
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From: Florence, MS
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The 255 pump. Yeah after the heads,cam, and intake upgrade lol. It's been acting up for a while now. I had an adjustable regulator and stock pump and for some reason when I would adjust the pressure wouldn't move anymore so I swapped fuel rails, New O'Reilly regulator, and the racetronix pump. Back when I first put the h,c,I on it had plenty of power. I got on it one night n something happened and it stumbled and it ain't ran right since. And thats been a few years ago
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Old Dec 16, 2012 | 11:02 AM
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RamAir95TA's Avatar
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Under throttle how low does the fuel pressure go?

As you open the throttle MAP pressure goes down so what you're seeing there is normal.
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