Fuel Pressure Dropping @ WOT

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May 24, 2004 | 12:00 PM

Ed Blown Vert

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Fuel Pressure Dropping @ WOT

While dynoing my car. I notice the my FP dropped from 60 - 40 psi. Even on the street at part-throttle, it drops to 50.

Before I install an inline pump. Is this normal and expected for the power I have??

May 24, 2004 | 04:04 PM

Nasty N8

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You are running out of pump. I would do an intank Walbro pump before an inline pump. The inline pump will help with keeping the pressure up but it will not give you any extra fuel. The inline just can not pull anymore fuel through the stock pump.

Nate

May 24, 2004 | 05:36 PM

Ed Blown Vert

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I hope it will be enough, I already ordered one.

May 24, 2004 | 06:06 PM

Nasty N8

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If you are dropping that hard already trust me it will not be enough even if it looks to be a steady pressure it will not be enough volume.

Nate

May 25, 2004 | 03:38 PM

Ed Blown Vert

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Thank, I was just making sure there was nothing else I should check.

May 25, 2004 | 03:41 PM

BIGBOS

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I would get a good intank in there as well.....

Having fuel pressure drop at WOT with your compression can be playing with fire

May 25, 2004 | 06:34 PM

Black LS1 T/A

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From: Raleigh, NC

Definitely save yourself some trouble and get a Walbro in there. I hate I dic'd around with an inline all that time.

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May 25, 2004 | 08:14 PM

Black LS1 T/A

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From: Raleigh, NC

Just shop the web for the best rate... (and someone who says they have it in stock now).

May 25, 2004 | 08:15 PM

#10

Black LS1 T/A

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I tend to patronize the sponsors here, since they try to accomadate our needs, even if it is a few dollars more (as long as they have it in stock or can get it to me when I need it).

May 25, 2004 | 08:27 PM

#11

Ed Blown Vert

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From: Sunny San Diego

I agree. I support the sponsors which support the site which help me make an informed decision.

So every kit will have everything I need for the install?

May 26, 2004 | 01:29 PM

#12

Nasty N8

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From: Lake in the Hills, IL

They do not make an easy kit for our cars to install the pumps. I have the pump and a install kit in stock. I am also offering them installed in the sender as an exchange basis.

Nate

May 26, 2004 | 07:35 PM

#13

iateyourcat

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Hmm, if my pressure is dropping from 62 to 56 would an inline help me? I've got a walbro intank and 42# injectors feeding a 427. Would a vacuum referenced regulater be better? Which one is easier to install?

May 26, 2004 | 08:18 PM

#14

Black LS1 T/A

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What is your Inj Duty cycle at peak RPMs? That kind of pressure drop does not sound unmanageable if it is consistent and enough fuel.

May 27, 2004 | 02:37 PM

#15

blu00rdstr

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From: Dublin, CA

Quote:

Originally Posted by Ed Blown Vert

After I installed a Ractronix and BAP, I had a pressure drop. Turns out my fuel filter was clogged, huge difference before/after new filter.

Try changing the filter, cheapest and easiest thing to do.

May 27, 2004 | 05:34 PM

#16

Ed Blown Vert

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Once of the first thing I changed. Same issue.

May 27, 2004 | 08:35 PM

#17

camaro98z28

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I changed my Fuel Pump in my 98 to a Walbro 255 pump and I noticed a big difference. It runs a 65 psi and only drops to 59 psi after hard driving

May 30, 2004 | 10:49 PM

#18

mike m

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ED I hate to say it but I had the same problem. Does yours drop just sitting in park revving the engine? mine did. I checked everything. I already had a t-rex fuel punp inline. I added a walbro pump in the tank and it did nothing. I even disconnected my fuel lines and blew them out to make sure something wasnt stuck. I bypassed the filter, the pump and nothing. I tried everything. I gave up and bought rails, braided lines, aremotive eliminator pump, regulator and a sumped tank. problem solved. and it cost around $2,000 to do.