Electric fuel pump question

[Kurbycar32]

My early 260z had a fuel pump installed in the exact same location and it was powered by a wire run around the front of the vehicle and tapped off of the resistor next to the coil.  My car had 2 fuel pumps that looked like this one, one at the tank and another in the engine bay:

 

 

I bought a new carter fuel pump and placed it by the tank in the rear at the stock location.  After messing with the electrical to power the pump on ignition on (instead of a few hundred RPM) I was able to keep the single, silent, cheap fuel pump and discard both giant loud ugly pumps.

[BenC]

On 10/28/2015 at 5:08 PM, Patcon said:

Power doesn't come from pressure!!!! Power comes from fuel! If it flows enough fuel then the pressure is irrelevant. Figure out if it is pumping enough fuel. Do the flow test from the FSM. These are not large engines they don't need a ton of fuel. 30 GPH is overkill.

If the pump won't flow enough at the pressure it is pumping then you won't have the fuel to make your power! 

The question is whether the pump will deliver the volume you need at the pressure needed at the pump to create the pressure expected by the carbs.

30 GPH is more than you will likely need (depends on how much power you are making).  However, as you can see from the chart, this Holley 12-428 pump, which is rated for over 30 GPH free flow, delivers less than half the flow at 4 psi which very likely is enough for about 130 HP in an engine with a 0.5 BSFC but not the almost 400hp that the free flow rating implies it can feed.

[Patcon]

True, but my seat of the pants logic goes like this. The tanks holds about 15 gallons at 3 psi can you think of a scenario where you burn all the fuel in the tank in an hour??? If you can't do that then you have enough fuel supply, give or take....

[BenC]

Ha!

That's interesting.  All the fuel pump cares about is whether there is fuel in the tank, and not how much.  All the carb cares about is whether the float bowl is full.  So, if you have fuel in your tank and the pump can keep the float bowl full, you are good to go.  The question is, What pump will it take to keep that float bowl full?

[jalexquijano]

BenC´s  question has not been responded! Will the airtex 8012s as shown in the post keep to float bowl full all the time, do you need to remove the Steel stock filter it comes with and replace it with a FRAM G2 filter? Cant believe there is not a better electric fuel pump than this one. I bought a carter p60504 in the past  and it did not had enough pressure:

http://www.summitracing.com/int/parts/crt-p60504/overview/

Is the Fram G2 filter better and less flow restrictive than the Mr. Gasket clear glass fuel filter??

 

 

[psdenno]

Fuel delivery is pretty straight forward.  Gas in tank, electric pump with pressure rating adequate for your Z, clean fuel filter(s).  If you've checked the pressure rating at the carbs and the carbs are working and adjusted correctly, you should be good to go.  You've tried a few pumps if I remember correctly.  Have you measured the current pump pressure or are you just guessing it's inadequate?

What amount of pressure is your current pump putting out?

 

Dennis

[siteunseen]

If you ride around on empty you will overheat the pump for sure. I have a stupid nephew that put five dollars worth of gas in his car when it was three dollars a gallon. My sister carried him to work for two weeks after his pump fried.