Building 550-600 hp mostly strip motor. I know 5/8" aluminum fuel line is overkill, but I'm sure this won't be the last motor in the car. Already have Holley Blue fuel pump, and I'll be using it. Hope to run fuel system as follows: Earl's 85 micron or Aeromotive 100 micron filter before the pump with -10AN feed line, 5/8" Aluminum line to 10 micron canister filter, then 5/8" line to Holley Blue regulator which I'm not all that thrilled about using, -8AN line from regulator to Y-block, -6AN line to each carb. I'm not to crazy about using a deadhead regulator, and may eventually change to a bypass style, as there's currently 3/8" aluminum line on the car (originally used as fuel line) which I should be able to use as a return line. Are there any drawbacks to using an obviously oversized fuel line? Any other problems with the system?

 

bigger is better in the fuel line world but 550-600HP and a Holley blue pump might not work out too well... plus you said "each carb"? That'd really be iffy with a blue pump.

 

Yea, each Holley single feed. Holley lists flow at 88 GPH @ 9 psi. I wouldn't run 9 psi, probably closer to 7-7.5, so flow would be slightly more than 88 GPH. Even so, if I were to overestimate BSFC at 0.75, the calculations would be as follows:

(600 hp x 0.75 lb fuel x 1 gal.) / [(hp/hr) x (6.2lb)] = 72.58 gal. / hr



So theoretically, it should flow enough. In reality, I'm sure it'll be close to it's limit.

 

I thought they rated flow at no load.

 

drawback?


well, you'll have almost a gallon of extra fuel to carry around... and explode if you get in a wreck.

i dont see any advantage to running that large fuel line, but i do see a significant weight and size disadvantage.

 

Apeiron,

Holley does list flow rates at no load flow, as well as loaded flow. In fact, I've attached the flow chart listed on their website for the Blue pump.

MrDude,

You're right in that I also see no significant advantage to running this large of a diameter of fuel line, as the planned motor won't require this much fuel flow. However, a 5/8" line leaves the door open for the possibility of a future motor that would require this much flow, without having to re-plumb the system. 550-600 hp would definitely need 1/2" line though, and the weight difference, fuel included, between the 1/2" and 5/8" is << 5lbs.

I'm most worried about the fuel "stalling" in the line on a hard launch, or reduced fuel pressure due to increased line size. Any opinions?

 

When i installed the drivetrain listed below I made sure everything from firewall back could handle whatever I threw between the fenders. Sumped tank, 5/8" fuel line to A2000 Aeromotive pump, to Aeromotive deadhead reg feeding -6 lines to bowls. Waaay more fuel system than this motor needed, but could easily feed a huge mountain motor if I had that opportunity.

Well, A2000 was not designed for continuos street duty and I burnt it up. Long story short I had to install a Holley Red to get through the points wweekend, first thing I noticed it went from carrying 8.5psi the whole track to 3psi after the 1-2 shift and got a lean sputter since it was running out of fuel. Next morning took spring out of the other truck I drive for a guy that runs a Holley black pump, installed that high pressure spring in my red pump and it carried 7.5 psi the whole track and no more lean popping and got my .3 back I lost after initally installing the Red pump.

So I bought a used Holley Blue from another racer that came with a Moroso hgih pressure spring, I took that Moroso spring outta the blue and installed it in the Holley Red I still have on my car. It buried the both fuel pressure gauges. Readjusted and now I carry 8.5 the entire track just as I did with that monster A2000 which is literally twice the size of the Holley pumps.

I know MANY guys that run the Holley deadhead reg. on their race/street cars with Holley blues with 3-5yrs on it and still going strong. Your set-up will be fiine as it is, but a return style regwill defiinately NOT hurt anything either.

Moral of the story: Dont waste your money on Holley blue or black pumps, buy a cheap Red pump and install Moroso's high pressure spring. All the Holley colored pumps are identical-the spring is the only difference.

 

Good to hear. I figured that the Blue pump which I already have would be adequate, even if not optimal, for the motor I'm planning. That being said, I have a few more fuel system questions:

What type of filter/filters did you run in the system? I'm considering running an Earl's 85 micron or Aeromotive 100 micron filter before the pump. Will the 85 micron filter impose any appreciable restriction in flow to the inlet side of the pump when compared to the 100 micron filter? For less than half the price, hopefully the Earl's will suffice. After the pump, I plan to run a canister type 10 micron filter.

As much as I'd like to install a sump in the tank, I have a feeling that I will end up making a pickup out of 1/2 or 5/8" line and placing it through the stock opening in the tank. If I mount the pump so that the inlet is lower than the bottom of the tank, and close to the tank as possible, will this setup be acceptable?

Obviously the pump nor the motor will require use of 5/8" line, but the sole reason I considered it was upgradability.

 

I was told by Aeromotive NOT to run any filter pre-pump as fuel pumps are not designed to sciphon, they're designed to push. But he said if I was deadd set on running a pre pump filter use the 100 micron mesh as this has the least restriction. I will tell you from experience, even the 30 micron steel mesh filter let crap by, so my advise is anty up the $80 for the Aeromotive high flow PAPER filter and install it pre-regulator. This way there's no caviation from the pump trying to suck with nothing there and you rcathcing all the bad stuff before it gets to the carb, spendy yes, but most canister style paper filter only flow like 90gph, so if you have a pump putting out 350gph like I orignally had, you can see the road block the fuel takes.
As far as brand, Aeromotive has been nothing but GREAT to work with and they've bent over backwards taking care of my problem and trying to figure out the best way to resolve them, so I would recommend Aeromotive based off great products and customer service that's second to none.

Alot of guys have the pump mounted lower than the pick-up in the tank, every car has different mounting options as does personal preferance. When you get money ahead, buy a sump and buy a BRAND NEW tank to intall it in, it'll be the best $150 you'll ever spend-I had crude problems in fuel system most of last year trying to use old tank in car.

Nothing wrong with spending the money to do it right once so your not redoing it again later....only rich people can do stuff twice-they can afford to.