Electric fuel pump

[Bunji]

My standard mechanical fuel pump may not be keeping up at full throttle (still under investigation).

If proven to be the case I'm looking at upgrading to an electric pump, does anyone know the required flow rate (L/min) and operating pressure (psi)?

Car is running a standard 1296 engine.

[Carledo]

Firstly, i'd be checking the lines for blockage, particulaly the one INSIDE the tank.

It's easy to say "Oh, the pump is a bit duff, lets put a new electric one on" and have it work, albeit for only a short time, then either the the blockage will get worse so you get the same symptoms back, or the electric pump packs up/burns out from overload.

Most available electric pumps are capable of delivering around 6psi which is too high for the rest of the system to cope with, so you will need a pressure regulator. The engine will run fine on 2 psi or a bit less. I don't know what that translates to in LPM but it's not a lot!

I've had a proprietary electric pump (a 6psi one with a regulator set to 2 psi) that was almost brand new but only produced a trickle of fuel from an open pipe. not because it couldn't pump (take the pump off and get it drawing off a can and plenty of pressure) but because it can't SUCK. The pressure rate is always stated, the vac side or suck rate NEVER is! The car in question had it's leccy pump mounted below the boot floor so was essentially gravity fed, but the pipe in the bottom of the tank was so constricted with crap it couldn't even suck enough fuel in to rev the engine above idle for more than a few seconds.

HTH, Steve

[cliftyhanger]

a thrashed car will do about 8-10mpg, at say 80mph. So maybe 45l/hr, or under a L/min
Carbs need very little pressure, 2psi is plenty.
don't be tempted by a cheap pump, I would get either a Facet with a seperate pressure regulator, or a Huco (which are available as a low pressure type, so no extra regulator required)

Saying all that, do check carefully that the pump is actually playing up.

[Carledo]

Another hasty PS!

A lot of the cheaper pumps on ebay these days seem to have an integral filter on the draw side. Which is all very well till the filter gets bunged up with crap and you have to buy another pump. True, these things average about £12 each on British ebay, probably little more than the price of a good quality filter! but still a PITA when it breaks down on a country road on a rainy Sunday.

Steve

[Bunji]

Have just gone for a run and when it started hesitating at open throttle I pulled over and check the pump - fuel level fine.

Perhaps it is a blockage somewhere as suggested.

A few days back it really lost power under full throttle, then produced a large backfire and cloud of black smoke. I think the driver behind had to race home and change their underwear!

[GinettaG15]

My standard mechanical fuel pump may not be keeping up at full throttle (still under investigation).

If proven to be the case I'm looking at upgrading to an electric pump, does anyone know the required flow rate (L/min) and operating pressure (psi)?

Car is running a standard 1296 engine.

the cars were designed in a way that the mechanical fuel pump can deliver more than enough fuel under all driving conditions:
e.g.: fully loaded boot, all passenger seats occupied, driving uphill with full throttle.

so in your case it must be something else....i never changed a mechanical fuel-pump on regulary used cars in 30y spannering.
i converted lots of ford x/flows in my recent years in the kitcar world from single downdraugt 32/36 weber to double 40ies sidedraugt carbs.....i NEVER hat to change the original Ford´s mechanical pump..and the cars were even used on the track!!

so check first the fuel-supply TO the pump b4 thinking to convert to electric pump

[dursley92]

Our cars have been around for Many years and standard mechanical pumps have always kept up very well so no worry about them being adequate.
More likely to be a blockage of some kind, maybe something that is floating about and gets drawn into the pipe?
Be worth checking your pipes and/or filters.

Having said that I do run Facet low pressure electric pumps on my Sprint engines, see Facet 60104 which is rated 1.5-4.0 psi with plenty of flow rate and no Filter King required.

[GinettaG15]

check the tank´s outlet and if there is maybe a filter installed (which might be neglected and blocked)