Hot Rods Mechanical Fuel Pump Limitations

I'm making a shopping list for fuel system components and am wondering about the pump. This'll be for a SBC of around 400 ci with a 671 supercharger and two 650 DP carbs on top of it. I'll be disappointed if I can't get 650 flywheel HP out of it...
I'm hoping to be able to use a mechanical pump, and already have an Edelbrock Victor series (#1711) that I've previously used on a blown but tamer SBC. These are sold as 130 gph pumps which is about 780 lbs/hr of gasoline I think. On paper, I think that's plenty of fuel. Anyone have experience with mechanical pumps at around the power level I want or higher. If its not a good thing, I'll plumb for an electric now instead of having to change things later, but would like to run what I already own...

 

How much boost? Boost levels are important to know when sizing a fuel system.

130 GPH sounds like a lot until you consider that it only does that when it is free flowing and may not keep up @ WOT. There are ways around that too.

A long time ago me and a friend were running a 2x4 440 in a class that required a mechanical fuel pump. we were limited by the pump (no mega mechanicals yet)and starving on the big end. So we upsized out fuel lines which was perfectly legal in class to 1/2" from 3/8 and that cured it.

Anyway so much BS that you didn't want to hear, how much boost?

 

I'm interested in hearing ya stories . Last time at 10% under driven I saw a max of 6psi on the boost gauge. I still own the same blower and pulleys so will run them for a start, but with a brand new combo don't really know what I'm going to get. It's for a streetable car so don't plan on seeing more than 10psi ever.

 

It is not until 10 psi that your fuel requirements get crazy. Around here we have been known to use a nitrous nozzle and a separate pump for carbureted engines running more that 10 psi.

I am thinking that you may be OK with what you got. Maybe @squirrel will chime in here he plays with huffed big inch motors all the time.

 

Some of those piston types claim up to 450 GPH

 

Those are higher than a cats back. I have heard good things about them though.

 

Made in the good ol' US of A with customer service that's second to none:

http://www.robbmcperformance.com/products/chevy1100.html

 

Wow. Gas tank vent better be LARGE!!!

 

The RobMc pump looks pretty impressive and still affordable. My Edelbrock pump is supposed to flow slightly more and has larger in and outlet fittings than the Carter which they compare to the RobMc so I think I'll set up with it knowing there's a bigger mechanical pump available if I need it. Thanks guys

 

I'm running the big block version of the Edelbrock pump#1712 with a 540 inch big block Chevy with a 1471 blower. Going on 3 years, no problems. Over 900hp. You'll be fine.

 

I have an electric on mine...interesting!

 

Sorry beaner it should be 450 GPH not GPM

 

I know its an old thread, but may i ask what fuel line size you use? Just wondering whats sufficient for that...

 

So...you fixed the problem of the air leak, and learned that you need to have two fuel lines to fix a fuel starvation problem that's actually caused by an air leak.



The 454 in my truck, with a Q jet on it, has a similar starvation problem at the track. But I'm pretty sure there's no air leak in the fuel line. Perhaps it needs a better pump? or a carb with bigger float bowls? (although they'd still not be getting enough fuel to keep them full) Or maybe I should add another feed line from the tank to the pump?

 

I was working on a P-30 a couple of weeks ago, this truck was factory equipped with a 454. It was an old SnapOn tool truck. It was built from the factory with a 1/2” fuel line from the tank to the pump. The mechanical fuel pump also had a 1/2” inlet on it. The outlet was 3/8” inverted flare(typical). I then looked up the application on Rockauto and sure enough, it was a 1/2” inlet pump.


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I worked on a motorhome years ago that had a 1/2" line from tank to pump, but I don't remember the 1/2" inlet on the pump. Great to know, thanks.

 

Wish I could use a mechanical pump on my old blown hemi....They are quieter than the electrics...I have nowhere to mount one anymore...

 

I am new to the forum, i dont know how to send a PM to someone. I would have, but just dont know how to. I still am wondering what fuel line size you used to make the setup work.. ? Thanks in advance!

UPDATE: Guys can someone help me out? How do i send someone a direct message? i click on someones profile but cant find a "send message" button anywhere :/