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Bigger Pump And Injectors?

  • Thread starter Thread starter Bob F
  • Start date Start date Jun 9, 2015

Bob F

Active Member
May 14, 2015
139
58
38
Roscoe IL
Jun 9, 2015
#1
  • Jun 9, 2015
  • #1
Hi Guys, I was wondering what you thought about going to a 255 fuel pump and 24lb injectors. Like my other mods I'm interested in building a solid foundation, driveability, as well as some hp or acceleration now.
 

modulistic

Active Member
Nov 26, 2002
383
30
29
Jun 9, 2015
#2
  • Jun 9, 2015
  • #2
not really needed unless you are upgrading heads and intake. wont hurt, but I would spend that money on gears or something first. You would also need a calibrated MAF, or a tune to make it work. if you just threw that stuff in there by itself you would probably run rich and throw codes.
 

bullitstang1313

Member
Jan 21, 2003
713
0
16
Indianapolis / Columbus, Indiana
Jun 9, 2015
#3
  • Jun 9, 2015
  • #3
What are your other mods? 255 fuel pump wouldn't be a problem, but I wouldn't put one in unless you need a new fuel pump. 24 lb injectors without a tune will cause problems. I'm not a fan of "calibrated" MAFs as all they really do is trick the system.
 

A5literMan

At least it is lumpy...
5 Year Member
Jul 30, 2011
4,674
2,343
194
Illinois
Jun 9, 2015
#4
  • Jun 9, 2015
  • #4
Unless you're making more than about 300hp (flywheel)I'd keep the 19's. The same goes for the fuel pump sizing. 255 is unnecessary unless you need that much fuel. Neither will "add" power they just "support" what your motor needs.
 

Bob F

Active Member
May 14, 2015
139
58
38
Roscoe IL
Jun 9, 2015
#5
  • Jun 9, 2015
  • #5
I already have 4.10 gears and many suspension mods like full length welded sub frame connectors, control arms, strange adj. shocks and struts, new upgraded brakes, and the Cobra replica wheels with 285/40/17 and 245/45/17 tires. Next week in goes the the Gripp strut bar, Steeda shock bar, BBK unequal lengths headers, BBK O/R H pipe,and Dynomax Ultra Flo SS cat back. I have a firewall adj. clutch cable with new quadrant, short throw shifter, Royal Purple trans fluid. Under the hood I have MAC fenderwell CAI, 70mm throttle body and EGR spacer, 3/8 inch phenolic manifold spacer, power pullies, 160 thermostat, Ford Racing 9mm plug wires, MSD cap, rotor and coil, new plugs, and timing at 14 degrees. This is an 88 speed density car.
 

Onefine88

Previously 89SSC18
10 Year Member
Aug 3, 2006
1,422
796
154
Jun 10, 2015
#6
  • Jun 10, 2015
  • #6
Like others have said, you are fine for awhile with the 19's. My car made 300rwhp/330rwtq naturally aspirated with the 19's.
You can run a 255 intank with any power level.
 

Bob F

Active Member
May 14, 2015
139
58
38
Roscoe IL
Jun 11, 2015
#7
  • Jun 11, 2015
  • #7
Thanks for the answers. I am not a mechanic but my thought was that with the 70mm throttle body, CAI, and 14 degrees timing, it would be good to give it a little more fuel. I also am planning maybe a new intake or porting the stock lower one. last question, wouldn't a 255lph fuel pump provide more fuel still using stock injectors?
 

A5literMan

At least it is lumpy...
5 Year Member
Jul 30, 2011
4,674
2,343
194
Illinois
Jun 11, 2015
#8
  • Jun 11, 2015
  • #8
Bob F said:
Thanks for the answers. I am not a mechanic but my thought was that with the 70mm throttle body, CAI, and 14 degrees timing, it would be good to give it a little more fuel. I also am planning maybe a new intake or porting the stock lower one. last question, wouldn't a 255lph fuel pump provide more fuel still using stock injectors?
Click to expand...
All you will be doing is pumping more fuel than you'll need. The excessive fuel will flow back to the tank unused. If you're still speed density be careful with mods or the computer will go into fits. You do not need bigger injectors! Period! You really don't need a bigger pump either with your mods. If you eventually plan on adding significant power ie a blower,and/or heads/cam/intake etc then you'll need the appropriate sized inj and pump. You can add the pump now if you want. But it will do nothing for performance at your combo's power levels. I highly recommend either doing a MAF conversion or a standalone computer system if you plan on serious future mods. If staying with the current mods no need to change.
 
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