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Fuel pump questions???

I pulled tank from the parts car, it had a v6 in it.  The tank was good and the fuel pump in the tanks looks new too.  It also had one on the frame rail.  Now the questions, can I use the in tank fuel pump with v8 carb engine?  I want to delete the frame pump.  What kind psi will the in tank pump?

Fuel pump questions???

Reply #1 –
Ditch both pumps and buy a new 190 or 225 lph pump.  Why guess when you can just spend $120 or so dollars and do it right.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Fuel pump questions???

Reply #3 –
Clean up on isle 9...missed the carb part but my earlier statement still stands in conjunction with this thread:

http://mustangforums.com/forum/5-0l-1979-1995-mustang/10393-efi-carb-conversion-using-stock-electric-pump.html

Lots of guys have converted to carb utilizing the stock fuel pump on the Fox Mustangs.  Some guys have gone as far as getting the stock pickup for the 83-85 Mustangs as they were carbureted but it all depends on how you want to go about it.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Fuel pump questions???

Reply #4 –
I got ya, I am going back carb, the car has no computer or engine wire harness, so I was going to use a carb.  I was hoping the stock in tank pump would be enough for carb.

Fuel pump questions???

Reply #5 –
The in tank pump can be used with a bypass set at 6-8 LBS!!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Fuel pump questions???

Reply #6 –
Bypass?  Is that a regulator?

Fuel pump questions???

Reply #7 –
Quote from: TOM Renzo;398897
The in tank pump can be used with a bypass set at 6-8 LBS!!!
Not if the car was a CFI set-up with the high pressure pump on the frame rail......the in tank pump is only a lift pump and peaks at about 2-3 PSI.
When I went from CFI to carb on my 84, I used both pumps with a Mallory 4309 regulator and it works well.
EDIT: The 4309 is a return style reg.
84 COUGAR/90 HO, 1.7RRs, performer RPM,700DP, equal length shorties, stainless EXH ,T-5,Hurst pro-billet, KC clutch, 8.8/ 4.10s, line-lok, bla ,bla, bla.
71 COMET/289,351w heads, 12.5 TRWs, 750DP, Liberty TL, 9"/6.00s, 11.9x @112 , bla,bla,bla.

Never shoot your mouth off, unless your brain is loaded! ....I may get older, but I'll never grow up!....If you're not laughing, you're not living!  :laughing:

Fuel pump questions???

Reply #8 –
NO just restrict the return line to 6-8 lbs. Another words you can build a system using the in tank low pressure pump if it exceeds 8 LBS. If memory serves me the in tank pump puts out 10 LBS +or - If it is closer to 8 lbs you can run it without a bypass. Check it with a gauge!!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Fuel pump questions???

Reply #9 –
Quote from: TOM Renzo;398907
NO just restrict the return line to 6-8 lbs. Another words you can build a system using the in tank low pressure pump if it exceeds 8 LBS. If memory serves me the in tank pump puts out 10 LBS +or - If it is closer to 8 lbs you can run it without a bypass. Check it with a gauge!!!
I did. If the car only had an in tank pump like the Mustang or Lincon etc, yes you can.
84 COUGAR/90 HO, 1.7RRs, performer RPM,700DP, equal length shorties, stainless EXH ,T-5,Hurst pro-billet, KC clutch, 8.8/ 4.10s, line-lok, bla ,bla, bla.
71 COMET/289,351w heads, 12.5 TRWs, 750DP, Liberty TL, 9"/6.00s, 11.9x @112 , bla,bla,bla.

Never shoot your mouth off, unless your brain is loaded! ....I may get older, but I'll never grow up!....If you're not laughing, you're not living!  :laughing:

Fuel pump questions???

Reply #10 –
Here is an in depth write up I did a while back...........just couldn't remember where I posted it....LOL.

 http://sbftech.com/index.php/topic,15112.msg146399.html#msg146399
84 COUGAR/90 HO, 1.7RRs, performer RPM,700DP, equal length shorties, stainless EXH ,T-5,Hurst pro-billet, KC clutch, 8.8/ 4.10s, line-lok, bla ,bla, bla.
71 COMET/289,351w heads, 12.5 TRWs, 750DP, Liberty TL, 9"/6.00s, 11.9x @112 , bla,bla,bla.

Never shoot your mouth off, unless your brain is loaded! ....I may get older, but I'll never grow up!....If you're not laughing, you're not living!  :laughing:

Fuel pump questions???

Reply #11 –
I have converted many a caddy from EFI to carb in the old days and it is very simple. Use the in tank pump only i think it is a low pressure unit. Been a while since i checked one. If it exceeds normal carb pressure of 6-8 LBS you can design a restrictor to send the excessive pressure back to the tank with the stock return line. No need for a regulator. I have dun this several times on the old EFI Caddys with perfect results. Using both pumps is silly as why would you want to reduce all that pressure when the in tank pump is a low pressure unit. Just me could be wrong!!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Fuel pump questions???

Reply #12 –
Besides the restrictor and dumping into the return, a large variable resistor or could be used to lower voltage to the pump... Varying voltage to pump to regulate pressure is how the returnless systems on newer vehicles operates(though not with a resistor, those use PWM)...

Supposedly the pumps for constant voltage aren't rated for varying voltage, but there have been instances of the older pumps used without issue... Running the pump at say 9v with the restrictor set for a carb would allow fine tuning pressure with the rheostat... With a fuel pressure gauge and rheostat mounted in the dash, pressure could be dialed from the driver seat... 


IF I ever get the 331 in the Bird it will be carbed and use a similar system...

Fuel pump questions???

Reply #13 –
If I use a fuel filter with a return on it, like from a 4.0 ranger, I can put a regulator by the carb and just use the in tank fuel pump?

Fuel pump questions???

Reply #14 –
Tried the fuel pump today, I get fuel to the carb, I have a pressure gauge no regulator.  I turned the key on and walk to the front of the motor and waited until the needle moved, it got to about 1.5lbs and then I noticed fuel coming out the vent tube on the carb, next to the inlet port on carb for gas.  Not sure if the psi from the factory intank pump (no frame rail pump) is to much or the floats on the carb are sticking?  I was thinking on getting a non return style regulator and then try?  any ideas?