Injector swap question
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Injector swap question
Currently own a 95' Lightning.. i am still on S/D with no tune and have the stock 19lb injectors running the beast. Now my buddy has a set of 24lb injectors he is going to give me... they are bosch so they will have better atomization for one. But the biggest issue, is can i run them without getting it tuned? I know it will run richer but what will be the power difference? Will it foul the plugs..?
Logistics Pro
Joined: Jul 2009
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From: Lansdale, PA
If you were to replace the 19lb with 24lb injectors with no tuning, you'd have to reduce fuel pressure to 27-30 psi to get it to flow the same fuel at idle. Adjust the fuel pressure WITH the vacuum line attached. That way at idle it is 27-30 and when you blip the throttle it will go up a little and richen up the mix a little.
But the down side is that with that low of fuel pressure it has a chance it won't atomize as well as higher pressure would.
Just retune the truck. You'll be so much happier.
But the down side is that with that low of fuel pressure it has a chance it won't atomize as well as higher pressure would.
Just retune the truck. You'll be so much happier.
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Mmmm, pretty sure they are not bosch, i know they only have the single pulse and not the quad which helps it atomize better with the newer ones. Maybe the technology changed over those couple of years. Either way I will wait than. Trying to get a job at this tuning place!
Lead Driver
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From: Rhode Island
They are Bosch. Bosch has always made Ford's injectors. Every EFI Ford I've seen from my Ranger to modern Mustangs have always had Bosch injectors.
I am also quite sure your truck has 4 hole injectors stock. The old 5.0 from the early 90's I took apart had 4 hole injectors, and a little searching on the internet shows that 5.8 trucks of that era also came with 4 hole injectors.
I am also quite sure your truck has 4 hole injectors stock. The old 5.0 from the early 90's I took apart had 4 hole injectors, and a little searching on the internet shows that 5.8 trucks of that era also came with 4 hole injectors.
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From: Calhoun GA
On a truck that is mostly stock with a few bolt-ons, 24's are not needed. If you have them laying around and just want to use them, then the best way would be to install them and tune it to get the best driveability possible.
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Mmmm, learn something new every day.. did not know bosch made them for all EFI fords. Well either way I am going to wait till i can tune it. To much can happen and cost me in the long run.
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Tuned
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From: Wildwood
I would think the computer would see a richer mixture through the o2 sensor and pull back the pulsewidth to bring the mixture back to programmed specs. pretty much negating the bigger injector is better theory.
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Fleet Owner
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From: Kentucky
That would be true in closed loop mode, but in open loop the PCM is running on a pre-programmed look up table. If you change something like injector size the PCM has no way of compensating for that large of a change in fuel supply.
Lead Driver
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From: Rhode Island
Ford's computers have set limit on how much they can lean or richen the fuel mixture before setting a check engine light. I am more then certain enough that 24 pound injectors would far exceed the adaptive limits.
Also, once you plant the pedal to the floor the computer exits closed loop mode, and fuels based on a default table as mentioned earlier. So once you put it to the floor, it will go extremely rich.
Also, once you plant the pedal to the floor the computer exits closed loop mode, and fuels based on a default table as mentioned earlier. So once you put it to the floor, it will go extremely rich.
FTE Legend
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From: Ottawa, Ontario
19lb injectors will support 275 no problem and over 300 with more pressure across the rail, and even a Lightning motor is in no danger of making that much HP unless you have been inside to change the cam.
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My truck as it sits never enters closed loop because it stays too cool. Which bugs me because i get about 2mpg worse on the highway since i redid my cooling system.
Now for the 19lb injectors.. i know i am pushing a little over 280hp right now and over 380tq with my set up now.I know how much the injectors will support but why would i worry about it if i get 24lb injectors. If i was going to push the 19lb injectors i might as well bump it up and not have to replace fuel pump or get a pressure regulator to get what i need. Makes life easier and with those 19lb i am more likely to run lean vs the 24lb in the same power band.
But over all i am going to get it tuned once i install them. Should gain 50hp with a descent tune and that with the new fuel pump i have and if i install the roller cam they said i can look at ~100hp gain... those solid rollers hold this motor back SOOOO much. Glad i have a f4te block.. roller ready
Now for the 19lb injectors.. i know i am pushing a little over 280hp right now and over 380tq with my set up now.I know how much the injectors will support but why would i worry about it if i get 24lb injectors. If i was going to push the 19lb injectors i might as well bump it up and not have to replace fuel pump or get a pressure regulator to get what i need. Makes life easier and with those 19lb i am more likely to run lean vs the 24lb in the same power band.
But over all i am going to get it tuned once i install them. Should gain 50hp with a descent tune and that with the new fuel pump i have and if i install the roller cam they said i can look at ~100hp gain... those solid rollers hold this motor back SOOOO much. Glad i have a f4te block.. roller ready
FTE Legend
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From: Ottawa, Ontario
How do you figure?
That's optimistic to say the least.
No factory Ford motor built in the last half century has solid lifters in it, you must be confused with something else.
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From: Calhoun GA
How do you know it never enters closed loop? If your cam and lifters are factory pieces, then you do not have a roller valve trane.
Tuning alone will not gain you 50hp on these trucks and it isn't very cost effective unless you have a power adder and/or heads, cam, intake.
I've seen 19lb injectors support as much as 350-400rwhp on quite a few trucks with bolts-ons and a power adder with tuning and increased fuel pressure, so you should be fine with what you have.
Tuning alone will not gain you 50hp on these trucks and it isn't very cost effective unless you have a power adder and/or heads, cam, intake.
I've seen 19lb injectors support as much as 350-400rwhp on quite a few trucks with bolts-ons and a power adder with tuning and increased fuel pressure, so you should be fine with what you have.
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Will check T-stat... was told if the motor doesnt get to a certain operating temp it wont enter closed loop on the OBD1 system
I know i am pushing that power now because i had it on a dyno at a local car meet several times for the fun of it and those were the numbers.. i will try to dig through some stacks of papers for the print out.
Now if it isnt hydro roller isnt it a solid roller? It is a 1995 and did not come with a hydro cam but is bydro ready becuase itis the f4te block.
The numbers i gave were from the shop i was at. They said with a custom ground hydro cam, larger injectors, and a nice tune they can net me 100hp peak gain. They have done it before. I am not sure if it is maybe luck on the other guys part but like i said. This is what i was told.
Why up the pressure when i will have 24lb injectors with less than 1k miles on them for free and in alot better shape than my current ones... still stock injectors. Will prob get a different intake while i am at it as well... Been looking at a Victor Jr.
I know i am pushing that power now because i had it on a dyno at a local car meet several times for the fun of it and those were the numbers.. i will try to dig through some stacks of papers for the print out.
Now if it isnt hydro roller isnt it a solid roller? It is a 1995 and did not come with a hydro cam but is bydro ready becuase itis the f4te block.
The numbers i gave were from the shop i was at. They said with a custom ground hydro cam, larger injectors, and a nice tune they can net me 100hp peak gain. They have done it before. I am not sure if it is maybe luck on the other guys part but like i said. This is what i was told.
Why up the pressure when i will have 24lb injectors with less than 1k miles on them for free and in alot better shape than my current ones... still stock injectors. Will prob get a different intake while i am at it as well... Been looking at a Victor Jr.