Will my 255lph pump be enough?

1

1990LXDropTop

New Member

Dec 4, 2003

430

0

0

Western Massachusetts

Nov 10, 2005

#1

• Nov 10, 2005

• #1

Right now I have a Walbro 255lph inline fuel pump and its fine for my current setup which is a stock block with Edelbrock heads, performer intake, and an e-cam. However I am getting a Novi1000 in the near future and will be running 5-6psi or boost. Will my 255 be good enough or will I need to run dual pumps?

 

tunedin302

I AM the law!!!

Jul 29, 2004

1,251

2

36

Pennsylvania

Nov 10, 2005

#2

• Nov 10, 2005

• #2

IMO, You'll be okay with the 255.

 

vristang

15 Year Member

Mar 31, 2005

4,933

101

124

Seattle

Nov 10, 2005

#3

• Nov 10, 2005

• #3

Depends on Hp level

You can't really get too much fuel pump unless you are talking about the $$$ expense, or possible noise. The return line takes car of extra flow/pressure.
Here are some recommendations that I worked out according to formulas I found in Four Stroke Performance Tuning by A. Graham Bell. Running at 80% of plump capacity helps ensure a long life from the pump. Hp is considered at the flywheel.

_____________________80% of Max______80% of Max

Ford EFI Options_______N/A Limit________Boost Limit
110 lph________________240 hp__________200 hp
155 lph________________340 hp__________280 hp
190 lph________________420 hp__________340 hp
255 lph________________560 hp__________460 hp

Not a major factor, but worth considering…
Also consider that a dramatically oversized pump will push large quantities of fuel through the fuel system and back via the return line. This process will add extra heat to the fuel which will lower its density. This is probably not an issue for otherwise healthy computer controlled efi motors, since the O2 sensor will help the computer to adjust the injector duration. This could however lead to increased wear on the injectors/pump/hoses of the fuel system.

 

Grn92LX

Fidanza Man!

Founding Member

Jan 14, 2001

6,819

64

129

New York

Nov 10, 2005

#4

• Nov 10, 2005

• #4

You should be fine but I would liek to see a 255 high pressure pump since boost will raise the fuel pressure a little (fpr's are boost sensetive so they raise the psi 1:1) or if you're running an FMU the fuel pressure will probably spike 70+ psi depending how much boost you see and what FMU disk you have. You can also get a bleeder valve to tune the FMU.