Question about fuel pressure...

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Jul 24, 2009 | 11:46 PM

UrSmked

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Staging Lane

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From: Columbia, MD

Question about fuel pressure...

I just installed a Granatelli fuel pump in my 2000 Trans Am tonight because the stock one went bad. The in line fuel pump is the one that came with the Charger. I have a Vortech V9 G Trim on the car with 42 lb injectors, a few other things but nothing related to the fuel system. At idle my fuel pressure sits at about 55. Cruising the fuel pressure stays at about 52-54. At WOT it drops to about 46-48. I was wondering if this is safe and if not, what can I do to fix this. Any help would be appreciated.

Jul 25, 2009 | 08:48 AM

OUTLAWZ RACING

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From: COLUMBUS GA.

Did you modify the bucket fo the walbro? also is the inline a 255 lph as well as the walbro? there shouldent be a drop like that on a new pump could be a restriction. also the walbro drwas more power that the stock pump did you by a hot wire kit aswell?

Jul 25, 2009 | 08:55 AM

UrSmked

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Staging Lane

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From: Columbia, MD

I just got the car the other day. I do not know what the inline fuel pump is. It is my understanding that the inline pump comes with the blower or the guy put one on. I thought he said it came with the supercharger kit. I did not make any modifications to the bucket when I put the pump in. Also, I did not get the hard wire kit.

Jul 25, 2009 | 08:59 AM

UrSmked

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Staging Lane

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From: Columbia, MD

One more thing, should the fuel pressure be increasing as the boost increases, or is it normal to have a small drop in pressure with forced induction.

Jul 25, 2009 | 11:29 PM

OUTLAWZ RACING

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From: COLUMBUS GA.

It should be a small dip then build and hold the fuel pressure. Yeah the grana pump is a wlabro just different name the stock wire dosent reall give it all the power it needs. Also you should remove the bucket and remove the bottom of it and make a window for the pump to prevent the bucket from running dry. look in the fuel sticky and you will see. I would also invest in a hot wire kit and look for the specs of the inline.

Jul 26, 2009 | 06:53 AM

Phat69

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You'd want the preessure to increase to counter the higher manifold pressure

Jul 26, 2009 | 08:45 AM

cputech

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From: Woodstock,GA

I also have the Vortech V9 Gtrim from Vortech. Car would idle at 57-59 ...then when in boost, the fuel pressure would drop to 48-50. I really hated the have the stocker intank along with the booster pump that came with the kit.

Purchased the Racetronics fuel pump and harness, which is in the process of being installed now. This "should" keep pressure constant.