Looking for Tips on building a fuel system

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340dartley

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Recently my vintage Bracket car started leaking fuel from the pusher electric pump near the tank. I did not build the car myself and am changing things as they wear out and break. The pump and fuel system near the tank are not a pretty site. I originally just planned to replace the pump and keep going but I can't leave well enough alone. I still am running the Carter mechanical pump as well.

Money is an issue but don't want to sacrifice quality and safety for money.

How much fuel volume should I shoot for. Currently I estimate the motor to make approx 400 or so at the crank, maybe a little less. If I am putting new parts on i would like to upgrade the potential so if I am running a more powerful motor someday. I would like to be able to support approx 500 hp. Would you keep using the mechanical pump as well. What size fuel line. I may have the stock steel line in the vehicle still. 5/16 I believe.
 
A Holley red pump with regulator set at 7psi using stock 5/16 pick up / tank and line was good enough for 11.70s in my 68 Barracuda mild 360. Nothing fancy or trick just basic set up.
 
could always ditch the mechanical pump and run a Holley blue pump, have that in 2 cars. the coronets blue pump has been in there for 6 years and has seen a lot of street miles as well. as for the fuel line I'm not sure about the 5/16 line, I use 8an from cell to regulator. I think the braided line is much nicer and easier to run, not too expensive either. but would require you to weld a sump in your fuel tank. that would support your future HP goals as well
 
my fuel tank is an old barrel style aluminum fuel tank. It has a threaded fitting on the bottom for fuel delivery.
 
Are you using today's crappy pump gas? If yes, then I would run the bare minimum amount of rubber fuel line as the alcohol/methanol content in today's pump gas swill will quickly deteriorate rubber fuel lines and aluminum parts in your carb.
I recently read an article saying one foot of rubber fuel line can lose 1 gallon of gasoline per year just due to fuel permeation. 20-feet of rubber hose equals a tank of gas per year - and that vapor will probably be in your garage.
I'd do as much solid line as possible, but if you're going to run rubber hose, even braided hose, make sure it's some sort of "vapor-guard" quality. It's more expensive but worth it.
 
Thanks for the advice on the steel hose. I am running a mix of 100ll av gas and 91 octane pump gas.
 
I won't comment on which pump to run, because someone always trashes my recommendations.

However, You need something on the order of 100GPH or more.

Also, no way in HELL would I run an electric with a manual pump. If the diaphragm in the manual pump ever fails, you will fill the oil pan up with fuel in short order.
 
I like the Holley blue pump with a regulator set at 6 1/2 pounds. 3/8s aluminum fuel line will support 500 ponies. 1/2 in line would be better but the Holley pumps use a 3/8s fitting Kim
 
Vintage bracket car so it's a race car only? Put a small fuel tank in front of the engine, if you don't have room lòok around for space behind a head lite or somewhere, run a 1/2" fuel line to a mechanical pump then a dash 6 line to the carb. Sweet and simple.
 
Bracket car - I'd always go electric. It's much easier for routine maintenance, takes less power to run, and easier to get if you have a failure somewhere. As RRR said - I would never use a pusher with a mechanical.

Kim's is a good basic setup and will last you even with a faster combo:

"...the Holley blue pump with a regulator set at 6 1/2 pounds. 3/8s aluminum fuel line will support 500 ponies. 1/2 in line would be better but the Holley pumps use a 3/8s fitting Kim"

Personally I like the AN and braided stuff for a race car where the lines are on and off a lot for various reasons.
 
I have 10AN from the tank to my pump, 8AN to 1/2" aluminum line to the front to 8AN to the regulator and the carb. The pump will be a matter of personal preferance. Don't forget good filters.

IMO remove the mechanical pump.
 
I was running 6.20's in the 1/8 with a Carter high volume mechanical pump with 3/8 fuel line and Auto Zone plastic fuel filter. I upgraded to a MagnaFuel electric pump and -10 line and picked up zero ET. My small block made 662 hp on the dyno.
 
running some pump gas with ethanol in it - skip the aluminum fuel line. I like the P4600HP federal mogul electric pump - no regulator needed
 
D-50394 said:
I was running 6.20's in the 1/8 with a Carter high volume mechanical pump with 3/8 fuel line and Auto Zone plastic fuel filter. I upgraded to a MagnaFuel electric pump and -10 line and picked up zero ET. My small block made 662 hp on the dyno.
Click to expand...

That's it. All these fancy pumps are way overkill if you're running Gasoline. Guys don't want to hear it but a HV mechanical pump is the way to go. Easiest thing in the world to set up and it's set and forget. I work with industrial pumps everyday and the key is large dia shortest possible delivery to the pump. I forget the guys name but in the 1980's the first guy to run 200 mph in a sedan - was a Sonny Bryant BBC with Nitrous in a Camaro, had a Holley blue pumps. So like I said before tank up front mechanical pump and have a nice day.
 
Very good information in the discussion. I have ordered a good pump for my purpose I think. I ordered the Carter 4600hp from summit. I will mount it in the same location as the original electric pump, back near the tank. I am removing the Carter mechanical pump.

Now I have to figure out my fuel line size. I was thinking 1/2 from the tank to the pump and 3/8 hard line to the carburetor lines. I will have to run new hard line as I believe the factory line is 5/16. The pump outlet size is 3/8 NPT. What kind of good fuel filter would you recommend and where would you mount it? Before or after the pump? would you plumb an inline filter or get a fancy spin on canister set up that you mount on a frame rail? Anyone run no filter at all? but don't worry I will be reusing it on another car I plan to start putting together that will be closer to stock.
 
100 micron before the pump and 40 micron before the carbs.
 
Use stock 5/16 line for return and ordered stock 3/8 fuel line. regulator at the carb.
For the record, i ran a carter elec. pusher to a carter mechanical pump for many years.
The reason why was the vapor lock problem that the pusher fixed.

Never had a diaphragm failure in 5 or six year... but had a regulator that only allowed the electric pump, to push a couple of pounds, to the mechanical pump. still if it had ruptured, i would probably not figured it out early enough to save my bearings.
It was a risk!
 
You can say "fancy pumps" are overkill if you want, but wait till you are in the pits in 90 plus degree weather running ethanol laced pump gas. You will wish you had an electric pump.
 
Been there with all of the pumps - if you want reliability, put it in the tank - OEM style. Cooler pump, quieter pump, cooler fuel with return line and way cleaner install. With the kits that are out there these days - its a no brainer :)

Like most important things in a cars build, do NOT skimp on fuel supply or system design. The above setup is used by ALL OEM's for a reason - It WORKS. Engineers the world over use the same system.

They're pretty smart AND well funded guys imho.
 
I installed the carter pump in the back next to the tank. I have not removed the engine mounted pump yet. I noticed the fuel pressure only comes up to 4 psi when the engine is shut off. It comes up to 6 psi once it is started. I am not sure if it is because of the mechanical pump dropping pressure or that is all the pressure the electric pump will put out.
 
Cudafever said:
Use stock 5/16 line for return and ordered stock 3/8 fuel line. regulator at the carb.
For the record, i ran a carter elec. pusher to a carter mechanical pump for many years.
The reason why was the vapor lock problem that the pusher fixed.

Never had a diaphragm failure in 5 or six year... but had a regulator that only allowed the electric pump, to push a couple of pounds, to the mechanical pump. still if it had ruptured, i would probably not figured it out early enough to save my bearings.
It was a risk!
Click to expand...

340dartley DID you read this right? ^^^^^^^^^^^^^^^^^^^^^^^^^^
Remember that is only a rubber diaphragm that your pushing all that pressure at. and when it ruptures.............that electric pump will fill the crankcase with FUEL, vary fast.

just bypass the pump on the block for now and find out how much that pump will push.
 
Yes I did read that. And that is the ultimate plan. I just have not removed it yet. Currently the braided fuel line comes off the mechanical pump outlet with a flaird fitting. If I remove the pump now I have to find a way to attach the fitting to the strait steel fuel line which has a rubber hose and a clamp. I am thinking this line is too small anyway as I believe it is 5/16. I would like to install at least 3/8 hard line back to the tank. I am still collecting parts for this so to keep the car mobile I installed the Carter pump and plumbed it to the fuel line temporarily. Also while a ruptured pump diaphram is a concern, this car has had a pusher pump feeding a mechanical pump for the last 30 years at least. I am keeping an eye on the oil level and condition.
 
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