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Discussion Starter #1
Wondering about a fuel pump with a supercharger. Currently stock but looking to upgrade bought a Walbro 255 but looking at the 340lph. Question is if I add the 340lph will I still have to add the T-REX pump when adding a Vortech supercharger? I have read its a much required thing when adding anything power.. Would rather have a 340 and not have the t-Rex to be necessary.

Thanks in advanced.
 

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No. You will need a 1:1 regulator, correct injectors for your setup and a way to tune.
 

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Wondering about a fuel pump with a supercharger. Currently stock but looking to upgrade bought a Walbro 255 but looking at the 340lph. Question is if I add the 340lph will I still have to add the T-REX pump when adding a Vortech supercharger? I have read its a much required thing when adding anything power.. Would rather have a 340 and not have the t-Rex to be necessary.

Thanks in advanced.
how much fuel at what pressure do you need?

you answer that, then you know what pump to select
 

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Discussion Starter #5
So I can install 47lb injectors, install the already purchased walbro 255lph fuel pump and completely skip the T-REX pump? That will make the install for the supercharger that much easier.

Obviously a good tune
 

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47 lb injectors are reasonably capable of 500-550 fwhp; you can push them further, but I absolutely wouldn't go past 600 fwhp. The 255 should be able to keep up with the 47 lb injectors assuming you don't go nuts with the fuel pressure. (keep it around 43 psi with a 1:1 boost rise)

The math works like this:
47 lb x 8 cylinders = 376 lbs/hr total injector flow at 100% DC. At 80% DC, you're at 300 lbs/hr. Divided by a BSFC of .6; you get 500 hp capacity. Raise the duty cycle, improve the BSFC or raise the fuel pressure, and you can get more capacity. For example - at 90% DC, and a BSFC of .55, you can support 615 hp. But on a blown street car, .55 BSFC can be tricky to hit, an 90% DC is pushing it.

A 255 lph pump can push about 67 gph of fuel. 1 gallon of gas weighs about 6-6.2 lbs. Let's use 6 lbs to keep things simple. So 67x6 = 402 lbs/hr - more than your injectors flow. But as you raise pressure, you reduce pump flow. Also, definitely run new, heavier gauge wiring to the pump. That's the biggest reason for pumps underperforming I've seen.

FWIW, a 320 lph pump got my car to 130mph trap speeds at 3,400+ lbs. I currently run a 450; and have no issues on gas (running 140 mph traps at 3,450 lbs). I think it would fall short on E85.
 

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So I can install 47lb injectors, install the already purchased walbro 255lph fuel pump and completely skip the T-REX pump? That will make the install for the supercharger that much easier.

Obviously a good tune
What motor is it and what vortech is it? As Alex's informative post above shows, depending on what sort of motor this is and what boost you want to run will dictate the fueling. On a stock displacement motor with a 10psi-ish SC, the 47's and 255 should be fine.
The stock regulator will keep it at 1:1 under boost, so don't listen to anyone that says otherwise.
 

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I have an Aeromotive 340lph Fuel Pump for sale...$80 shipped....text me (262)620-1134 if interested


Sent from my iPhone using Tapatalk
 

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Discussion Starter #10
Is a slightly modded 302. Intake upper and lower, gt40 heads rockers, cam, looking at installing a Vortech v3SCI with the Ford Racing 47lbs. I like the idea of it being a self contained unit. I will look into intercooler and the pulley after I make a final decision. Any thoughts would be great. Just looking to push 5-600 hp as it is more of a weekend street car to stomp on when I want.


Is the aeromotive brand new?
 

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Just 500-600hp? Go straight to 60lb injectors then and the larger fuel pump, as you are going to need to boost that thing to get that power with your heads. Plus you will eventually run into other problems running high boost with those heads without putting a good gasket/arp bolts/studs in them. I'd also start saving for a dart block cause you will need it soon.
 

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yeah, 500 is all I would want to go on a stock block. Mine made 458 with 8.5 pounds, letting out before bouncing off the 6k rev limit. Back when I was pushing 13.5 pounds, I don't know what it made but, I am sure it probably wasn't going to live very long.

and personally, I like a meth kit over the intercooler idea. The intercooler will keep it closer to ambient temp all the time but, there is an octane boost with meth AND that is one less thing in front of the ac condenser.
 

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... a slightly modded 302. Intake upper and lower, gt40 heads rockers, cam, looking at installing a Vortech v3SCI with the Ford Racing 47lbs. I like the idea of it being a self contained unit. I will look into intercooler and the pulley after I make a final decision. Any thoughts would be great. Just looking to push 5-600 hp as it is more of a weekend street car to stomp on when I want."
These points are mutually exclusive with just a V3. My similar H/C/I motor (full mods in sig link) with a V2 at 10 PSI put down 400 RWHP (corrected). Note that this is with no intercooler or meth. 425 would likely have been possible, but I wanted to stay safe with the tune. This said, 500+ HP would likely split your factory block down the middle, and will require more than mild mods to achieve.

Indy is correct. You need to determine your (realistic) power goals, then size your injectors and pump sizes to match. Also, bigger is *not* better when it comes to fuel pumps, since all the extra/unused fuel is simply circulating through your hot engine compartment, increasing its temperature. Use the smallest pump that will safely support the system requirements (or meet future needs if future improvements are planned).

..
 
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