how hard is it to go from an electric fuel pump to a mechanical one , any info would be greatly welcome, by the way really like the site.
I assume you are switching to carburetor???
yes why else switch to a mechanical pump
you're best bet is to use a low pressure electric pump. I do believe our timing covers aren't machined for a mech fuel pump. And i think the covers that have the fp boss the reverse rotation wp wont bolt up.
louie
i beleive you would first have to know what engine... if its the 5.0 u can get it set up.. there may or may not be mech fuel pump boss. it would be located on drivers side timing cover i beleive. and i do beleive SOME 3.8's also had mechanical fuel pumps
anybody have some info on this low pressure pump, how its set up, and what about the pump in the tank does that stay in or does it come out. boy oh boy lots of ??s thanks ahead of time for any info
What year and what engine are we talking about?
1985 5.0 efi
If it is a T-Bird or Cougar it is a CFI (Central Fuel Injection). It is a carb. type device with two injectors in it.
If you have the two fuel pump system, you have a low pressure pump in the tank and a high pressure pump inline.
The inline pump would be just forward of the right rear wheel and packaged with the fuel filter.
(http://users.rcn.com/jroyle/fuel%20pump.jpg)
I don't know if the in-tank low pressure pump will support a carb or not. But it may be worth a try.
84FILA was looking into this, but I don.t know how it worked out.
thanks for the info, and your right it is cfi
The low pressure pump will work out fine with a carb. I done the conversion from cfi to carb and used the low pressure pump in the tank.
do you need a regulator or anything like that
i believe that duel fuel pump thing was isolated to the 83 and far and few betwoeen 84's. I also noticed that the duel fuel pump system was associated to the duraspark I system as well IIRC when i was looking into this.
like mentioned, tell us if you have a fuel pump on the filter (highly doubt it on that year though).
either way, if your not going to drill a hole in the tank then dropping it is gonna have to happen. You cant just suck fuel through the existing tank pump and simply hook up an external low presure one. it will cause a volume restriction imho although ive never really tried this.
Most of your external pumps are intended to boost the presure but you may find the lower volume/presure type on the carb'd subaru ect.
External pumps can be found on early 90's vans and trucks but the presure is too high.
Ive often thought about what i would do in your case, i would try running any old elec pump but use an inline rheostat on the hot wire and dial in the resistance required to reduce the RPM of the pump to produce the required psi.
then you could install the correct wattage/resistor.
softtouch,,
yeah i really wish 84fila would get off his a@@:D and get the numbers on that low presure in the tank pump,,as well as the external. i have a note on it waiting on his reading.:D
ok,, perhaps you have the information on the presure. Yours sounds like it was plug and play. What is your fuel presure? what year is that car and which dizzy ign system was it?
Lowering the voltage to the pump would be a very bad idea. Electric motors don't like low voltage - it eats the brushes and commutator bars up. Newer cars with returnless fuel systems use pulse-width-modulation to vary pump speed (but the voltage stays the same).
You can find aftermarket low pressure high volume electric pumps from just about any carb manufacturer (Holley, Edelbrock, etc).
Oh, and just getting a timing cover with fuel pump boss won't get you going, either - you also need something to operate the pump. EFI cams don't have the required lobe on them to operate a mechanical fuel pump. I'm pretty sure you can get a bolt-on fuel pump eccentric for EFI style cams though...
in parallel with the motor i meant to say,,,, that way you maintain the voltage. I get stuff bass akwards sometimes.
anyway thats how a lot of variable speed dc motors work. Similar to the AC motors with a frequency drive instead.
Was'nt the cams from that era provisioned for a mech fuel pump still ? 1985 CFI would put him in the earlier years castings.
My cam has a spinner ring for lack of a better discription . Even my old 3.8 was provisioned for a mech pump but it had a lobe instead.
My car is an 84 with cfi. It has just a low pressure fuel pump in the tank. I believe they are rated for 38-42 gph @ 6-8 psi. It works fine with a carb.