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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

255lph pump

  • Thread starter Thread starter luckythirteen13
  • Start date Start date Sep 23, 2005
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luckythirteen13

New Member
Jul 19, 2005
648
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0
Anaheim, CA
Sep 23, 2005
#1
  • Sep 23, 2005
  • #1
will a 255lph in tank pump support a sc motor making 425rwhp+ with 42# injectors? i have the 255 now and have the t-rex but was wondering if i really need it. how exactly does having two pumps on the same fuel line work exactly?
 
D

dwhiskie

New Member
Sep 18, 2004
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0
Sep 23, 2005
#2
  • Sep 23, 2005
  • #2
Thats all I have, no T-rex and no problems
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Sep 24, 2005
#3
  • Sep 24, 2005
  • #3


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.



_____________________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



I recommend considering future plans when deciding on a fuel pump.

You should be ok. With more power though you will most likely need the secondary pump.

jason
 
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luckythirteen13

New Member
Jul 19, 2005
648
0
0
Anaheim, CA
Sep 24, 2005
#4
  • Sep 24, 2005
  • #4
looks like im probably going to be needing the second pump. are those numbers crank or rear wheel hp? i know i wont hit 460rwhp but ill pass 460 at the crank for sure
 

Dbeck002

New Member
Apr 30, 2005
710
0
0
South florida
Sep 24, 2005
#5
  • Sep 24, 2005
  • #5
I think your main problem is the injectors. 24 lbs are too small for 400 RWHP. pump should supply enough fuel for a car running 10s, injectors are just small.
 

Ozz

I think I have a problem here.
Founding Member
Jul 27, 2001
3,514
66
109
Canton, MI
Sep 24, 2005
#6
  • Sep 24, 2005
  • #6
Dbeck002 said:
I think your main problem is the injectors. 24 lbs are too small for 400 RWHP. pump should supply enough fuel for a car running 10s, injectors are just small.
Click to expand...

He said 42#.

a 255 pump should be fine, but a T-Rex would not be overkill either. From what I hear, it draws when required.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Sep 24, 2005
#7
  • Sep 24, 2005
  • #7
luckythirteen13 said:
looks like im probably going to be needing the second pump. are those numbers crank or rear wheel hp? i know i wont hit 460rwhp but ill pass 460 at the crank for sure
Click to expand...

Those are for crank hp, I believe. I will double check when I get home tonight.
 
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luckythirteen13

New Member
Jul 19, 2005
648
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0
Anaheim, CA
Sep 24, 2005
#8
  • Sep 24, 2005
  • #8
dan is refering to they 24# injectors i have now. they handled with an fmu up to 350rwhp but they were going lean. that was also below 4500rpm. all the dyno runs were cut at 4500rpm cause my fuel system just couldnt hack it
 
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