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What size fuel pump?

  • Thread starter Thread starter Dino
  • Start date Start date Oct 7, 2010

Dino

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#1
  • Oct 7, 2010
  • #1
The fuel pump on the 86 GT has gone bad. The car is currently at my fathers place and he'll be changing the pump in the spring. What size pump should we go with? The limited mods it has are listed below...
 

2000xp8

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#2
  • Oct 7, 2010
  • #2
Pretty much any size pump will work fine for those mods.
If you plan to do some more minor modding in the future like heads, go with the 155lph.
If you plan on supercharging it (in the near future) use the gss340 255lph.
 

Dino Dino Bambino

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#3
  • Oct 7, 2010
  • #3
Is Dino your real name 'cause it's also mine.
 

jrichker

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#4
  • Oct 7, 2010
  • #4
2000xp8 said:
Pretty much any size pump will work fine for those mods.
If you plan to do some more minor modding in the future like heads, go with the 155lph.
If you plan on supercharging it (in the near future) use the gss340 255lph.
Click to expand...

Good advice, take it and run with it...
 

Dino

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#5
  • Oct 8, 2010
  • #5
Bullitt95 said:
Is Dino your real name 'cause it's also mine.
Click to expand...

No, it was a nickname
 

Dino

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#6
  • Oct 8, 2010
  • #6
2000xp8 said:
Pretty much any size pump will work fine for those mods.
If you plan to do some more minor modding in the future like heads, go with the 155lph.
If you plan on supercharging it (in the near future) use the gss340 255lph.
Click to expand...

Since the car is currently speed density would a larger fuel pump hurt the idle?

Are there any disadvantages to running a 155lph pump with my current mods, until such a time comes that an intake and heads enter the picture?
 

2000xp8

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#7
  • Oct 8, 2010
  • #7
Dino said:
Since the car is currently speed density would a larger fuel pump hurt the idle?

Are there any disadvantages to running a 155lph pump with my current mods, until such a time comes that an intake and heads enter the picture?
Click to expand...

Changing the fuel pump out won't effect anything.
Fox mustangs have a return style fuel system, meaning all the excess fuel goes back to the tank.

Realistically you won't even know you changed it.
 

Hi-Po

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Oct 8, 2010
#8
  • Oct 8, 2010
  • #8
2000xp8 said:
Changing the fuel pump out won't effect anything.
Fox mustangs have a return style fuel system, meaning all the excess fuel goes back to the tank.

Realistically you won't even know you changed it.
Click to expand...

According to Kenne Bell larger fuel pumps will heat up the gas and make it less efficient hence why they recommend their Boost-a-Pump kits.

I am not running a Boost-a-pump myself, but the way they explained it made some sense so I decided to not go larger than 190 lph for my setup (see sig).

I notice that a lot of guys here seem to run very large pumps though, so perhaps it doesn't really matter.

Anyways, here is what KB says about the matter:

http://www.kennebell.net/KBWebsite/Common/pdfs/FuelPumpTech.pdf
 

2000xp8

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#9
  • Oct 8, 2010
  • #9
Hi-Po said:
According to Kenne Bell larger fuel pumps will heat up the gas and make it less efficient hence why they recommend their Boost-a-Pump kits.

I am not running a Boost-a-pump myself, but the way they explained it made some sense so I decided to not go larger than 190 lph for my setup (see sig).

I notice that a lot of guys here seem to run very large pumps though, so perhaps it doesn't really matter.

Anyways, here is what KB says about the matter:

http://www.kennebell.net/KBWebsite/Common/pdfs/FuelPumpTech.pdf
Click to expand...

Even if there is a couple of degrees difference, it's not enough to change anything.
KB mainly sticks to returnless systems, if you look at their charts and info for the most part 86-95 information is incomplete or completely missing.

Never the less, the 155lph pump is perfect for almost all occasions on a foxbody where there is no Supercharger.
 
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