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  Topic Review (Newest First)
09-01-2018 02:40 PM
AlessandroM So to round my venture up: against popular recommendation here I bought the cheapest and weakest fuel pump from facet (plastic type) which is rated 1,5-4psi. I did this after asking multiple reseller about quality differences between these and the cylindrical ones. They basically said that there is no difference in how they work and in how they are built apart from the benefits listed here (integrated washable filter + one-way valve, which some plastic-type also have). The posi-flow costed me almost a third in comparison to the cyl-ones so I thought I may just give them a try and report here for science ;-).

It's working now like it used to with the mech pump and I don't seem to find a difference with either the disc-type or the diaphragm type regulator. Oh and its also noticeable more silent than the cube one but that is what they state so no wonder.

Thanks a lot for all your opinions.
09-01-2018 01:46 PM
jacky71
Quote:
Originally Posted by papajam View Post
The mechanical pump is a stock Fispa as fitted to a 1750. The only requirement was if fuel could be pushed through the pump via external means (ie an electric pump). A look at the fuelpump flow diagram (click below) suggested that fuel arriving at the pump would open the inlet and output check valves and pass straight through the pump. The very scientific test method to check this was to blow into the inlet side. When air came out the outlet, the mech pump was deemed suitable.

For the electric pump, it needed to be able to pass fuel with only suction on the output side (engine running on the mechanical pump) with the pump turned off. Again, the scientific test method was to suck on the output side. It worked. So the pumps were hooked up in series and the rest is history.
I've long forgotten what model the Facet, pulse type electric pump is but it was originally for a carb conversion so the pressure should be close. The pressure actually does not matter as the fuel pressure is regulated by a stock Fispa filter/regulator.
Hi Papajam,

Thanks for your advice.

I tried to blow into my new fuel pump from inlet side, a Pierburg mech type. The air come out, I hear the membrane vibrate.
When I finish the restoration, I will try to combine an electric pump as you suggested.
Thanks
08-25-2018 06:08 PM
papajam @Tom Frasca
It looks like the Facet cube type I'm using but again, I don't know exactly which one I have.
08-25-2018 05:45 PM
gprocket The pump I'm using came from Pierce - I haven't used them yet but I like the form factor and I've been told they are very reliable. Begs the question: Why then did we need a redundant system?
08-25-2018 04:51 PM
Gordon Raymond I use the one pictured below, either from Phoenix Racing in Wisconsin, Centerline, or off E-Bay, whichever is handy and less costly at that time. Never had a problem with this one.
08-25-2018 04:36 PM
Tom Frasca @ papajam and Raymond ...this one..??

https://www.rockauto.com/en/moreinfo...sn=434&jsn=434
08-25-2018 09:03 AM
Gordon Raymond Jim's discussion above is very similar to the pre '68 V12 Ferrari method, which also used a (identical) Fispa FRB 11 regulator. The Ferrari system does include a return line with electric pump on the rear line, and mechanical on the front line. In use, the idea was to keep fuel cool to prevent vapor lock.
08-25-2018 07:05 AM
papajam
Quote:
Originally Posted by jacky71 View Post
What features must the pumps have for this system?
Quote:
Originally Posted by Tom Frasca View Post
Which pump do you use?
The mechanical pump is a stock Fispa as fitted to a 1750. The only requirement was if fuel could be pushed through the pump via external means (ie an electric pump). A look at the fuelpump flow diagram (click below) suggested that fuel arriving at the pump would open the inlet and output check valves and pass straight through the pump. The very scientific test method to check this was to blow into the inlet side. When air came out the outlet, the mech pump was deemed suitable.

For the electric pump, it needed to be able to pass fuel with only suction on the output side (engine running on the mechanical pump) with the pump turned off. Again, the scientific test method was to suck on the output side. It worked. So the pumps were hooked up in series and the rest is history.
I've long forgotten what model the Facet, pulse type electric pump is but it was originally for a carb conversion so the pressure should be close. The pressure actually does not matter as the fuel pressure is regulated by a stock Fispa filter/regulator.
08-25-2018 03:28 AM
Tom Frasca
Quote:
Originally Posted by papajam View Post
That's exactly the reason I use an electric pump as well. But only to fill the bowls. Then the engine runs on the stock mechanical pump.
The 30 some odd year old cube pump I'm using, mounted in the rear of the car, is activated via a toggle switch that is fed from the ignition switch. It pulls fuel from a stock, top discharge fuel sending unit. To start the car, turn on the ignition and then electric fuelpump. The electric pump then pushes fuel straight through the check valves in the mechanical pump (the check valves prevent fuel drainback FROM the engine, not to the engine). After the bowls are filled, turn off the electric pump and then start/drive the car as normal. The mechanical pump will pull fuel straight through the cube pump. A stock filter/regulator is installed in the factory location between the mechanical pump and the carbs.
An added benefit to this setup is that in the event of a stock pump failure, just turn on the electric pump.
We had rarely driven the car, now that we(my wife and I) are retired we drive it with more frequency. I will install pump as you described. Always good to have a backup plan.(I do carry a spare). And, of course-some ignition bits and a AAA gold card!!! Which pump do you use?
08-25-2018 12:06 AM
jacky71
Quote:
Originally Posted by papajam View Post
That's exactly the reason I use an electric pump as well. But only to fill the bowls. Then the engine runs on the stock mechanical pump.
The 30 some odd year old cube pump I'm using, mounted in the rear of the car, is activated via a toggle switch that is fed from the ignition switch. It pulls fuel from a stock, top discharge fuel sending unit. To start the car, turn on the ignition and then electric fuelpump. The electric pump then pushes fuel straight through the check valves in the mechanical pump (the check valves prevent fuel drainback FROM the engine, not to the engine). After the bowls are filled, turn off the electric pump and then start/drive the car as normal. The mechanical pump will pull fuel straight through the cube pump. A stock filter/regulator is installed in the factory location between the mechanical pump and the carbs.
An added benefit to this setup is that in the event of a stock pump failure, just turn on the electric pump.
Hi Papajam,
very interesting upgrades. What features must the pumps have for this system?
Thank you
08-24-2018 11:53 PM
jacky71
Quote:
Originally Posted by Gordon Raymond View Post
Not the exact one, jacky71, but they all function in a similar manner. I've seen small and larger versions, with and without pressure gauge. If you google Filter King, or look on E-bay you can see they make a few variations. Current production uses all fuel proof diaphragms and seals. These have been available for years, so I do not know how far back components were "fuel-proof". I do know that unless updated with a new diaphragm and bowl seal, original FISPA FRB 11's will leak, and original diaphragms will harden and fail. I restore / update a lot of these.
Racers use the larger Filter King, and like the built in gauge. I usually recommend the one with the gauge as these are not OEM FISPA for concourse, but used as replacements or for function. The gauge makes set up easier than temporary or permanent install of a separate gauge.
Thanks for the very comprehensive answer as always.
Initially, I need a regular setup, so I was thinking of rebuild this model of regulator rather than a Fispa.
Buying today a revision kit I should be sure to find materials suitable for actual fuels.
Some advice on where to buy spare parts?
Thank you
08-24-2018 12:58 PM
alfaparticle It depends to a degree on the size of the float valves in your Webers. Bigger valves are less tolerant of higher pressure. My 45DCOE152's get sufficient fuel at WOT/7000 rpm with 2.5 psi. The float valves are 2.0 and 3.5 psi will cause them to flood.
08-24-2018 09:59 AM
Tom Frasca I read this post ...a few questions my mechanical pump went bad on my 1600. I replaced it (mechanical) and an inline filter. Other then having to crank it to get fuel to the carbs when it its for a while, all is well, and it starts immediately everytime and runs the stock 1600 with zero issues. Gordon keyed in on several issues , but the unknown is what is this fuel system connected to? My own preference is to K.I.S.S. if your running a stock setup. I do not have a pressure regulator and the stock 40 MM webers are set to spec.I rarely push it to 6000 but it will....and the plugs and AFR are all good..
08-24-2018 09:21 AM
alfaparticle
Quote:
Racers use the larger Filter King, and like the built in gauge. I usually recommend the one with the gauge as these are not OEM FISPA for concourse, but used as replacements or for function. The gauge makes set up easier than temporary or permanent install of a separate gauge.
Not just racers
08-24-2018 08:10 AM
Gordon Raymond Not the exact one, jacky71, but they all function in a similar manner. I've seen small and larger versions, with and without pressure gauge. If you google Filter King, or look on E-bay you can see they make a few variations. Current production uses all fuel proof diaphragms and seals. These have been available for years, so I do not know how far back components were "fuel-proof". I do know that unless updated with a new diaphragm and bowl seal, original FISPA FRB 11's will leak, and original diaphragms will harden and fail. I restore / update a lot of these.
Racers use the larger Filter King, and like the built in gauge. I usually recommend the one with the gauge as these are not OEM FISPA for concourse, but used as replacements or for function. The gauge makes set up easier than temporary or permanent install of a separate gauge.
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