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Fuel injectors

  • Thread starter Thread starter didon
  • Start date Start date Jun 14, 2020
D

didon

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Jun 14, 2020
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rochester ny
Jun 14, 2020
#1
  • Jun 14, 2020
  • #1
question i want to go from 19lb to 24lb injectors i have 87 mustang gt no mas do i need one? installing 70mm throttle body also
 

08GT500

5 Year Member
Jul 12, 2018
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Jun 15, 2020
#2
  • Jun 15, 2020
  • #2
Hi,
You’re desire is to swap injectors with running a MAP sensor & not a MAF, looking to see if it can be done with no issues?
-John
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
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Jun 15, 2020
#3
  • Jun 15, 2020
  • #3
didon said:
question i want to go from 19lb to 24lb injectors i have 87 mustang gt no mas do i need one? installing 70mm throttle body also
Click to expand...
Sure you can.
But should you? Your only gain will likely be an ill running car at best, swap in a MAF, now that's a good idea.
For more info on what you can do go here:

Progress Thread - Technical Thread/how-to Index

Guys, if "that should be a sticky," then please reply to this thread with the link to your suggestion and why you think it should be added. How to determine if a thread should be included: - Does the topic address a common fox 5.0 owner's needs? / Is it a frequently asked question? / Is it...
www.stangnet.com
 
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08GT500

5 Year Member
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#4
  • Jun 15, 2020
  • #4
Bingo!
-John
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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polk county florida
Jun 15, 2020
#5
  • Jun 15, 2020
  • #5
08GT500 said:
Bingo!
-John
Click to expand...
what again? I never win at bingo
 

jrichker

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Jun 16, 2020
#6
  • Jun 16, 2020
  • #6
didon said:
question i want to go from 19lb to 24lb injectors i have 87 mustang gt no mas do i need one? installing 70mm throttle body also
Click to expand...
What sort of mods do you have that require more fuel flow? Aftermarket cylinder heads, intake manifold, cam, or stroker crank? A 70 MM TB won't make any difference without one or more of the items in the list. The engine is a air pump: unless it pumps more air, it does not need more fuel.

Speed Density uses Manifold vacuum (MAP), Throttle position (TPS) and RPM, & Air Temperature (ACT) to guess how much air the engine is pulling in. Then it uses all of them plus the O2 and ECT sensors to calculate the air/fuel mixture. It is dependent on steady manifold vacuum and minimal changes in airflow from the stock engine configuration to maintain the proper air/fuel ratio. Change the airflow or vacuum too much and the computer can't compensate for the changes, and does not run well. Forget about putting a supercharger, turbocharger or monster stroker crank in a Speed Density engine, because the stock computer tune won’t handle it. Every time you seriously change the airflow through the engine, you need a new custom burned chip to make the engine run at peak performance.

Mass Air uses a Mass Air Flow meter (MAF) to actually measure how much air is being pulled into the engine. The computer uses this information and inputs from the O2, TPS, ACT, ECT, RPM and Barometric Pressure (Baro) sensors to calculate the proper air/fuel ratio. It is very tolerant of changes in airflow and vacuum and tolerates wild cams, high flowing heads, and changes in displacement with minimal difficulties. Just remember that large changes in airflow require more fuel than the stock fuel system can deliver. At that point, you will need larger injectors and a larger fuel pump to make the engine run like it is supposed to. Larger injectors can be used with either an aftermarket calibrated MAF or a custom dyno tune. This makes it possible to use the stock computer with engine displacements from 302-408 cu in, and make many modifications without a custom dyno tune chip. Put a new intake manifold on your 331 stroker and the computer figures out how much more fuel to deliver without having to have a new chip burned to accommodate the extra airflow.
 
Last edited: Jun 16, 2020
Reactions: 7991LXnSHO

08GT500

5 Year Member
Jul 12, 2018
918
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Massachusetts
Jun 16, 2020
#7
  • Jun 16, 2020
  • #7
General karthief said:
what again? I never win at bingo
Click to expand...
General karthief said:
what again? I never win at bingo
Click to expand...
well..Stay with what works, bet on the Ponies!lol
 
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D

didon

New Member
Jun 14, 2020
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0
1
rochester ny
Jun 25, 2020
#8
  • Jun 25, 2020
  • #8
General karthief said:
Sure you can.
But should you? Your only gain will likely be an ill running car at best, swap in a MAF, now that's a good idea.
For more info on what you can do go here:

Progress Thread - Technical Thread/how-to Index

Guys, if "that should be a sticky," then please reply to this thread with the link to your suggestion and why you think it should be added. How to determine if a thread should be included: - Does the topic address a common fox 5.0 owner's needs? / Is it a frequently asked question? / Is it...
www.stangnet.com
Click to expand...
thanks for the input i really dont
General karthief said:
Sure you can.
But should you? Your only gain will likely be an ill running car at best, swap in a MAF, now that's a good idea.
For more info on what you can do go here:

Progress Thread - Technical Thread/how-to Index

Guys, if "that should be a sticky," then please reply to this thread with the link to your suggestion and why you think it should be added. How to determine if a thread should be included: - Does the topic address a common fox 5.0 owner's needs? / Is it a frequently asked question? / Is it...
www.stangnet.com
Click to expand...
thanks for the info. i really dont know much about the car.it was my brothers car he passed away 3yrs ago. and he was to sick to tell me anything about it.
i do know it has nitrous bbk headers cai.he did say at one time before he got sick that car could do low 11s. trying to find out best way to do upgrades thank you for your advice
 

nickyb

I gotta say i never painted my nuts, Never Ever
15 Year Member
Apr 3, 2009
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nevada
Jun 25, 2020
#9
  • Jun 25, 2020
  • #9
Low 11's ? I doubt much stock stuff left, post some pics of engine.
 
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