Fuel pump? How much is enough.

[jenks21]

I am nearing the end of my build and gathering up the final touches. One of the finals is the fuel system.

From what I have got from my reasearch is that you need a 1/2 pound of fuel per hour for every horspower. Divide that by six and that is the gph that you need wich is obviously effected by pressure.

So say for instance you have a big block with a dominator around the 800 hp mark. So you would need a pump that would fow 67 gph at pressure. A holley blue flows 88 gph at 9 psi, according to the summit mag it supports 550 hp so wtf? A holley black is 120 gph at pressure and says its supports 750 hp. Am I missing something?

I am probably going to go with a mallory, but I was just using the holley for sake of arguement. What are the mud guys experience with brands. I have heard that the holleys are prone to problems, and others say the opposite. Of course forking over high dollar for a bg pump is not an option.


Along the same lines is the regulator. Some you can buy the combo with pump. Some come with return, some don't. Is it easier on the pump if you run a return, or does it not matter? I do have a spot for it on my fuel cell.

Thanks for the help.

later
jenks

[Proeliator]

My motor is around what you described, and I use a Mallory 250gph electric unit. Some buddies of mine with similar setups have had success with the same pump.

Your Holley blue and blacks cannot support motors at this level, despite what the marketing says.

[OKMudn]

1st: The blue pump will not keep up...the black pump might come close but could still cause problems keeping the engine fueled properly.
2nd: Stay away from the BG pumps and regs...Summit Racing tech support said they have had LOTS of problems and would not recommend them for anything.

I'm running an Aeromotive A2000 pump and regulator on a healthy big block...over the 800hp mark. Single custom built dominator that flows 1460cfm and the pump provides plenty of fuel even for lengthy bog pit runs.

[jenks21]

Thanks for the help.

I see that the mallory 250 has a bypass built into the pump so that answers my question there.

So I would think since the holley black wouldn't be up to the task more than likely the mallory 140 comp woundn't fit the bill either.

Are you guys running a 40 amp relay to run them?

Later
jenks

[OKMudn]

I am running a 30 amp relay i believe.....and my regulator is a bypass style regulator, they keep fuel pressure more consistent than static pressure regulators.

[jenks21]

I just found this after doing some more surfing.

http://go.mrgasket.com/pdf/TS_FuelSys.pdf

Looks like I have a little problem with my formula. I need to multiply by two which would be 140 at pressure.

800hp / 2 = 400 400/6 = 67 67 x 2 = 134 gph @ pressure

Again thanks for the help. I guess I could of answered it myself with some more SEARCHING. lol

But still like to know the real world experiences from the guys who are in the sport I run. Not some jockey on the end of a phone telling me it will work.

later
jenks

[OKMudn]

When you buy a pump go one step bigger than what you need right now if you can afford to. When used with a good regulated return style regulator you will have no issues with overfueling as long as you get the pressure set right and your float level adjusted correctly.

The reason I recommend going bigger now is because if you ever plan to make that big block any healthier than it is you will need it then, so why spend the money twice. I've been through that on fuel and ignition systems both.

[jenks21]

Okay well I got a line on a mallory 250 fuel pump and a 3500m fuel filter for a reasonable price.

Proeliator what regulator are you guys running. There are a few mallory recomends. the cheapest is a non return wich I would probably route using a y block to send return to the tank, or is it best to use the bypass off of the pump?

from mallory's site: Use regulator part number 4200, 4201, 4300M, 4301,
or 4316M for best performance. The 4316 is the cheapest at 140 and they go up from there.

later
jenks

[Proeliator]

I'm a big fan of Aeromotive when it comes to fuel products, and I'm running an Aeromotive regulator. I'd be running an Aeromotive pump, but I came across a smoking deal from a buddy on the Mallory 250 and since its a great pump as well thats what I'm using. Normally, I'd say to NEVER run a "dead head" regulator but the Mallory 250 is internally regulated with a return outlet right on the pump. Point being, its not a big deal with this particular pump. Just run a quality low restriction filter (I use the 100 micron stainless -10 AN aeromotive filter) between the pump and the tank using a -10 AN line, and then a -8 AN return line from the pump to the tank, and a -8 AN line to another filter (between a 5-10 micron) and then to the regulator followed by the carb.

[IcallhimGeorge]

I bought an Aeromotive A1000 pump and A1000 return style regulator. -10 feed line with a 100mic filter before the pump and a -8 return line. I must say Im extremely happy with its performance now and Ive got room to grow.


A quick ballpark for figuring MINIMUM gph (gallons per hour if you are a douche) is this:

dead head regulator - hp x .23 = gph of free flow needed

return style regulator - hp x .17 = gph of free flow needed


A Holley Black pulls 140gph advertised MAX.

550hp x .17 = 93.5gph

Its close but personally I wouldnt chance it. The last thing you want is this thing crapping out at 6000rpm. The Mallory 250, Aeromotive A1000 or Magnafuel 500 are all very good pumps.


Give Joe Mayabb www.joesraceparts.com a shot if there arent any sponsors here that can help.

[jenks21]

I just picked up a brand new mallory 250 and mallory 5 port reg for $200 bucks. So that is what I got there. Need the filter mallory 3500m.

Sponsors? WTF are those. I pretty much gave up on that shit anymore. I have a few, but nothing major. I will take any help given of course. How is he to deal with? Is he a buddy of yours or have you just ordered from him.

Later
jenks

[IcallhimGeorge]

Originally Posted by jenks21

mallory 5 port reg

are you running 2 carbs?

Originally Posted by jenks21

Sponsors? WTF are those.

Im talking about Pirate4x4 sponsors. Buying from the people who support the site. Ive given up on sponsors for my truck as well.

Originally Posted by jenks21

How is he to deal with? Is he a buddy of yours or have you just ordered from him.

I met him through 460ford.com. He got my attention when I priced something small...maybe some AN fittings and it was much cheaper than Jegs. I kept doing business with him on a few things here and there and ultimately placed an order for around $2500-3000 worth to finish up my motor. I met him in Indiana the first of this year and we've hit it off as pretty good friends ever since.

Give him a shot at pricing what you need. If hes cheaper do business with him.

[jenks21]

Originally Posted by IcallhimGeorge

are you running 2 carbs?



Give him a shot at pricing what you need. If hes cheaper do business with him.

No just one carb. It was a package deal. If I would of bougt a pump and reg new for a go fast store I would of been in 450 bucks. So I got a brand new pump and reg for 200. Figured I couldn't go wrong. Plugs are cheap.

I will give him a lookup. To see what he can do.

thanks
jenks

[Proeliator]

Originally Posted by jenks21

I will give him a lookup. To see what he can do.

thanks
jenks

I've heard nothing but good about Joe. I'll be giving him a call myself for a new N20 package for the Dominator.

[jenks21]

Originally Posted by Proeliator

I'll be giving him a call myself for a new N20 package for the Dominator.

Eventually for me too, but have to get my rig finished first.

What system and how big are you going to go. I like the zex plate, but haven't researched to see if they have a plate for the dominator, other than that I will probably do the port injection. But like I said down the road for me. And have yet to do any research on timing ect.

later
jenks