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MG MGB GT V8 Factory Originals Technical - Fuel pump choice
What are you all doing from a fuel pump point of view?
I need a new one for the CB (the old one is pretty old), should I go for a standard MGB pump or one of the (much more expensive) facet types?
I am keeping a standard V8 set-up, no hot cams or the like, and I was going to mount it in the boot no matter what I chose.
I have a weber dual port manifold/carb set up and the instructions say as long as the pump doesn't produce over 6psi it should be OK.
Any suggestions or views?
|My carb is a Holley (390cfm)I use Holley fuel pump (red) with fuel press regulator (holley), the fuel filter is a Bosch. The Holley pump is very noisy.|
|Liam, I used a standard MGB pump with my Ford 302 (600 cfm Edelbrock) conversion and it ran fine as long as I didn't use full throttle for more than about 5 seconds! I then found the remnants of an old double-ended SU pump at a wrecker and rebuilt it - with an additional new solenoid - and - no further problems! It works fine, has added safety as you could still get home on one "end" if there was a failure, and looks the part. Better still, you can buy them new - Moss? Mine has points but there is an electronic version without points available too. Worked for me. Good luck, Bob.|
I've used Facet and SU... but I very much prefer the Mallory.
This is the sort of question where you might want to check the archives. You'll find many of us have already expressed our opinion on the topic several times.
|The original SU will be adequate for a BOP/Rover but will be short on pressure for a Ford 302 conversion on the dragstrip (been there - done that!). As you indicated, 6psi should be the max that you'd need without unwelcome things going on in the float bowls.|
For the record, I use a Carter 4070 and have a Facet (Purolator) plumbed in series with a cockpit mounted switch.
|I'm using one of the SU electronic pumps on my stock Rover 3.5, 500 cfm Edelbrock. Works great.|
|I use a Facet type pump and carry a spare in the trunk. I have been using the pump for the last 5 years without an issue. There are good luck / bad luck stories on these. If you end up using a Facet pump you will want to use some soft rubber mounts. Without the mounts the pump is embarrassing loud. The pump has no problem keeping up with the fuel needs of the engine. |
|You might try that feeder pump I use for my high pressure EFI pump.|
It is small and quiet and pumps at a very high rate.
The feeder pump is made by Pierburg in Germany and is called an Auto-suction vane cell pump. Stock no. 12001. It can deliver 0.5 bar when used as a primary pump. It cost $95 Australian (apply exchange rate to get an idea what it might cost locally)
|The fuel presure needed for a carb engine and WOT (wide open Throtle) is 3 psi. A bad located pump will not be able to pump as needed by the engine.|
The facet or similar pump from Napa is not loud when it's not properly mounted, this type of pumps needs fuel gravety feed. There are pumps that do not need to be mounted lower than the fuel tank such as MGB's this pumps are two stage.
Peter has such type of pump and can be mounted in the same location as the stock pump.
The real trick is to feed the pump of your choice by gravety first. Many engine tuning problems are cause by poor pump or bad pump location.
|So, is it the case that if I want to use a Facet I can't mount it in the trunk/boot, and have to have it lower down i.e. outside/underneath the floor ?|
|YES! Gravity feed the pump.|
|hello,again, mr. guzman,, in your above post you mention a fuel pump that mounts into the orig. spot [i assume my 75 has orig. mounting??]pump goes thru a rubber ring thats cut into the upper flange in trunk, has a metal cover over the back of pump, covering up the hot wire & the ground wire simply screws into one of the holes, holding the cover plate. this is on the right side of trunk just above the gas tank & spare tire.you mentioned peter has this type of pump,, is this peter a guy?? brand name?? parts supplier?? and do you know where i can get one [east coast] not that that matters,, and also the part # for pump. my car is B.O.P. conversion that i bought already done i'm pretty sure the pump in it is the orig.one i havent noticed any fuel starvation problems, but after car sits for a couple of days it requires a wack with minature hammer then it works fine till it sits again for 2 or 3 days. just want to replace it before Tenn. meet, & clean up points on orig.one & keep for spare.. as always i appologise for my total ignorance,and thank you once more in advance for your help.....|
|I have used Facet pumps on my V8 for many years.|
As the car is used for rallying as well as being used more conventionally rather than carry a spare pump I have two pumps plumed in with a change-over switch.
I've had two pumps fail in the last ten years. It's important that they are properly fused, the last failure caused a fire in the loom!
|I was hoping to use a rover p5/p6 mechanical pump mounted on the timing cover. Would this be able to cope with a Holley 390? I used to have nightmares about the old su pump on my first mgb and so was keen to get rid of the electrickery!|
|Denny, what I meant is to locate the pump below the tank, just like the early B's. The pump is sold by Napa or Moss Motors. This pumps when properly mounted will last a very long time.|
Follow the pump instructions (mount pump below the tank level.
If using a Facet universal pump, install a fuel filter before the pump.
Make sure you have a good ground.
Install a fuel pump relay and use good quality wire and crimp ends correctly. (many of the electrical problems are caused by badly crimped wire ends.
Check voltage and the pump wire.
Peter is a person who posted above by post.
Peter has a vane pump, this pumps are auto prime.
This pumps can be purchase from Holley, Careter and Facet also has one. The pumps can be bought at any speed shop or auto parts.
About Facet pumps: there have always been two basic types. The "solid state" pumps (which are only recommended to about 150hp) and the cylindrical pumps. I'll assume that when we talk about Facet pumps we're all talking about the latter.
My Facet fuel pump installation followed all Bill Guzman's excellent recommendations to the letter, yet the pump was quite loud and it died very young. For the record, it was mounted on nifty rubber mounts... The Mallory pump I mounted in its place has been much quieter and has already lasted years longer. And I mean years! I've been driving my Buick-engined BGT for almost fifteen years now.
About Facet pumps, Bill wrote: "These pumps when properly mounted will last a very long time." and earlier "The facet or similar pump from Napa is not loud..."
So, I was curious why Bill's experience would be so different from my own, and the experience of so many people I've known. Doing a quick Google search, I found this statement on the Pegasus Racing site: "The Cylindrical pumps (formerly 'Interrupter' pumps) now have solid state internals instead of points for even greater reliability." Perhaps that explains some of the difference. (Maybe they really are better than they used to be. IMHO they used to be junk!)
A little off topic... but when I was in college my friends and I built little Kawasaki-powered open-wheeled racecars, and we used the little Facet "solid state" pumps. We went through two of them in short order one weekend, before realizing we'd blown a voltage regulator and that the electronics in those fuel pumps weren't internally protected against over-voltage. (Shame on Facet!) Luckily, I'd driven my MG there, and we were able to race with its SU pump.
|There is a pump sold by AutoZone over here that is an excellent choice for the CB cars where the mount is alongside the tank. It is cylindrical with inlet and outlet on opposite ends, comes in a 2-4.5psi and a 5-9psi version, and cost about $40. They seem to hold up well and deliver adequate fuel, and they are reasonably quiet, being a solenoid type pump. Makes just enough noise that you can tell it's running but not enough to hear when running.|
This thread was discussed between 03/02/2006 and 11/02/2006
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