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SpecialK
Here's some interesting information concerning fuel pumps and Weber Carbs. Throw the Facet pump in the trash fighting19.gif

http://www.racetep.com/webfuelspark.html#webfuel
thesey914
Hmmm not sure about this. Could be just one persons opinion promoting their product (on the other hand its not that much more $$). I wouldn't image that carbs require the volume they're suggesting, even at WOT 60 gallons seems like a lot of fuel. 4PSI is right but it is vacuum/airspeed that causes the fuel to atomise not fuel pressure.
SpecialK
Good point! More research required <_<

Here's the 'Home page':

http://www.racetep.com/weber.html

They do have a bunch of info for Webers of all flavors. You left coasters may be familiar with the place (check address)
J P Stein
That is a good lookin' fuel pump. I'll think about gettin' one from NAPA .....after I have tuning problems from my Facet. It is a noisy SOB, sure nuff.
lapuwali
The Facet is a lot quieter if you rubber mount it. I have one Facet that's solidly mounted and I can hear it over the engine. Another is rubber mounted and I can barely hear it with the engine off.
914ghost
The good thing about the Facet pumps I've installed is they have an internal regulator that shuts them off when pressure is reached..
I still run a carter rotary pump though.
Bob O
J P Stein
QUOTE(lapuwali @ Mar 23 2004, 07:08 AM)
I have one Facet that's solidly mounted and I can hear it over the engine. Another is rubber mounted and I can barely hear it with the engine off.

Mine is soild mounted. I can't hear it when the engine is running, tho......can't hear a 747 taking off either laugh.gif
adam912
I was wondering about the Facet I installed so I pulled the hose off the carbs and directed the flow into a bucket. Plenty of delivery as I remember. Hmmmmm.

Adam912
Jake Raby
Guess why they like the carter better???

I know the wholesale cost of both!

The Facet works just fine !!
SpecialK
Okay, if Jake says Facet pumps are worthy, then who am I to argue. He is the type IV carburetor king. pray.gif
campbellcj
I noticed that PMO sells Pierburg pumps.

I have an OEM 914-6 pump; who makes those? The writing is really hard to make out without pulling the little sucker out of the car. Works pretty well, though.
zehrschnell914
Now I don't know what to do. I read the information on the racetep website and it made sense to me (as long as everything is being represented correctly). I finally have my car running and need to tune (& rejet?) my new carbs. I was about to start pricing the Carter pump, but now I'm not sure.

My car has an Amguage pump, no regulator and dual Weber 44's. Any suggestions?

Mike
J P Stein
QUOTE(zehrschnell914 @ Mar 24 2004, 11:57 AM)


My car has an Amguage pump, no regulator and dual Weber 44's. Any suggestions?

Mike

Yes....check your fuel pressure. Happy range for Webers is 3.5/4.5 psi.

Never heard of Amgauge....not that there's anything wrong with that. smile.gif
7391420
When the Faucet-or similar, (I think I have a red-line pump) ticks, IE all the time, does this mean that the fuel is delivered in a pulse and not a linear flow?

I have also pulled the line on mine and it seems to be a nice even flow to me.....
zehrschnell914
Thanks JP. I've never measured fuel pressure before, but I'm assuming I can buy the appropriate guage at an auto parts store. Would the correct method be to pull the fuel lines off at the carbs and check the pressure at each one? I am assuming here that there will be some pressure loss along the way.

Mike
lapuwali
There are "interrupter" pumps, like the box-like Facet, which pulse the fuel, and rotary pumps, like the Carter (and the Bosch EFI pump), which don't. For a carb, there's not really any difference. All the pump has to do is keep the float bowl full. Any pulsing in the fuel delivery is irrelevant, unless the pulses are so few and far between that the float bowl level changes between them. The Facet pump will run until the pressure on the feed side (pump to carb) exceeds some set value, which it will if the line is full and the needle valve remains closed (pump running, engine off). You usually hear the pump warbling when this pressure is reached.

With Webers, you can't exceed a certain fuel pressure or you push the needle valve off its seat and the float bowl overflows. I've heard figures from 3 to 5 psi as absolute never-exceed-this limits. I have an adjustable regulator set to 3psi on my car.

As long as the float bowl doesn't empty, there is no minimum pressure. All that's important is the flow rate. However, for a given fuel line ID and flow rate, there will be a set fuel pressure. Pressure is easier to measure than flow, so some pressure range is specified at the low end to account for "normal" sized fuel lines. If you had extra large fuel lines, you could still deliver plenty of fuel to the bowl with very low pressure. If you have extra small lines, you need a higher line pressure to get adequate flow. With 8mm (5/16") lines, 3psi appears to deliver enough fuel for a 40IDF on a 1.7. It may very well be enough for a 48IDF on a 2.3, I have no idea.
J P Stein
Some folks put in a permanent fuel pressure gauge. Not a requirement confused24.gif
Your FLAPS should have something...NAPA is gud.

Shouldn't be any discernable pressure loss, me thinks.
si2t3m
I have a bendix fuel pump for my webered 3.0l. Also have a /6 Bosch fuel pump doing nothing as a remplacement. The bendix pump is monted in the front trunk with rubber isolators. I can barely hear it.

Marc-André
ChrisFoley
I have a Facet pump in my street car with a 2.2 liter and a Holley red in the race car. Both cars have the cheap rotary pressure regulator. The race car is set to 2 1/2 psi (I never measured it) and fuel delivery has never been a problem at 110+ mph.
I do have a mech. fuel pressure gauge on the dash that reads line pressure so I'll know if the pump ever shuts down.
I installed a facet type pump on my tow rig with a big block. No regulator is installed but the distance from the tank to the engine is at least 20 ft. Works fine.
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