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Discussion Starter · #21 ·
Apples to oranges, injector placement is different which affects both differently. Can the 6 hole injectors atomize fuel better, perhaps, but even so it’s negligable at best, especially in the older pushrod motor.

Also, the ecu will not be able to adjust to the bigger injectors. The ecu expects x amount of fuel given a pulse. With bigger injectors more fuel is injected given the same pulse time. The ecu cannot adapt to the difference in fuel flow and will run rich. This is evident in the mustang world when Ford switched from 19 to 21 pound injectors in late 01. The model years with the 21 pound injectors ran rich in stock form because Ford did not adjust the tune.
If im not mistaken the ecu will help tune and regulate the air to fuel, ive heard the ecus do a decent job at tuning itself with small mods done to it, my thing is that ive heard that the stock injectors are already maxxed out pretty much, so if i were to throw in a small cam or possibly just a tune it would cause injectors to go bad fairly quickly and i would have to pay for stock set that im gonna change out farily quicker, even if i gain 1 mpg it would be a win, small things add up
 

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If im not mistaken the ecu will help tune and regulate the air to fuel, ive heard the ecus do a decent job at tuning itself with small mods done to it, my thing is that ive heard that the stock injectors are already maxxed out pretty much, so if i were to throw in a small cam or possibly just a tune it would cause injectors to go bad fairly quickly and i would have to pay for stock set that im gonna change out farily quicker, even if i gain 1 mpg it would be a win, small things add up
Yes the ecu can adapt to changes but in the case of bigger injectors it’ll still run rich. I’ve never heard of the injectors being maxed out from the factory. Ford 19# orange top injectors are good to about 300 hp at the rear wheels.
 

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Discussion Starter · #23 ·
Yes the ecu can adapt to changes but in the case of bigger injectors it’ll still run rich. I’ve never heard of the injectors being maxed out from the factory. Ford 19# orange top injectors are good to about 300 hp at the rear wheels.
i didnt mean maxed out but on the verge of being above the 80% usage, i might be wrong though
 

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Discussion Starter · #26 ·
Nowhere near that in stock trim. Maybe around 200 at the rear wheels.
After looking around for a bit on some forums and some guys putting their 351/302 on the track, you are correct on them holding more than stock just as long as the fuel pressure is raised by 10-15 psi give or take, they will only support around 235 whp or around 270 crank at stock fuel pressure, thats why i see some guys switch over to the 24# when doing slight mods.
 

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After looking around for a bit on some forums and some guys putting their 351/302 on the track, you are correct on them holding more than stock just as long as the fuel pressure is raised by 10-15 psi give or take, they will only support around 235 whp or around 270 crank at stock fuel pressure, thats why i see some guys switch over to the 24# when doing slight mods.
I would figure out your end goal and get the right size injectors to support that power level. And make sure they’re the correct design. Ford used certain injectors, such as the 39# injectors used on the 03-04 cobra, that have less than ideal spray patterns for this motor. Those injectors have two nozzles to spray on two intake valves at once, which wouldn’t be ideal in a pushrod motor.
 

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Discussion Starter · #28 ·
I would figure out your end goal and get the right size injectors to support that power level. And make sure they’re the correct design. Ford used certain injectors, such as the 39# injectors used on the 03-04 cobra, that have less than ideal spray patterns for this motor. Those injectors have two nozzles to spray on two intake valves at once, which wouldn’t be ideal in a pushrod motor.
i found some that i like but im gonna take a gamble on them bc they are ¨refurbished¨ bosch 6 hole injectors, they are on ebay but its a business that rebuilds them, their profile seems legit....for $105 i figured id give it a shot
 

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i found some that i like but im gonna take a gamble on them bc they are ¨refurbished¨ bosch 6 hole injectors, they are on ebay but its a business that rebuilds them, their profile seems legit....for $105 i figured id give it a shot
I’d check out the reviews on eBay and check them out through the BBB. I bought some refurbished injectors off eBay myself. They work just fine but have developed surface rust.
 
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Sent from my F-150 using Tapatalk
 

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Discussion Starter · #34 ·

Sent from my F-150 using Tapatalk
Thankyou, i normally dont ever buy stuff off of Ebay
 

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it has a 351w in it, it sat up for a little bit and when I got it, it ran somewhat rough, struggled to stay idling, rough first crank
I replaced fuel filter and spark plugs and it ran the same so I replaced the fuel pump because there was no sock on it and the tank was rusted to hell and back(I cleaned the tank out)
Started it up and it ran the same, 1 week later and it won’t start at all, I am pretty positive it’s a fuel issue since it bogs down when I press the gas
im thinking injectors are clogged so my question is if I use mechanic stethoscope and I turn it over will I be able to hear the injectors?
If y’all have any other ideas of what it could be please help I am stuck and it’s my daily driver
Perhaps I am too old to ask any questions about this but, you mention a 351 Windsor engine and for those who will think me an idiot to use the word engine, all devices that use fossil fuels to run are engines, and only those devices that use electricity to run are motors. But one thing I would have to check first would be the distributor and if it is in good shape and also the timing, despite new plugs and wires if during packaging of the wires they can get damaged and also the ends which connect into the distributor cap and spark plugs can get loose and not make a good enough connection for proper firing.
 

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Perhaps I am too old to ask any questions about this but, you mention a 351 Windsor engine and for those who will think me an idiot to use the word engine, all devices that use fossil fuels to run are engines, and only those devices that use electricity to run are motors. But one thing I would have to check first would be the distributor and if it is in good shape and also the timing, despite new plugs and wires if during packaging of the wires they can get damaged and also the ends which connect into the distributor cap and spark plugs can get loose and not make a good enough connection for proper firing.
Not quite.

A motor can use internal combustion OR electricity. It is a machine that provides the motive power for a machine.

An engine is an object or mechanism that serves as a source of power.

I'm not trying to be a smartass, just lettin' ya know. I did double check the Oxford dictionary before I wrote this.

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Discussion Starter · #37 ·
Perhaps I am too old to ask any questions about this but, you mention a 351 Windsor engine and for those who will think me an idiot to use the word engine, all devices that use fossil fuels to run are engines, and only those devices that use electricity to run are motors. But one thing I would have to check first would be the distributor and if it is in good shape and also the timing, despite new plugs and wires if during packaging of the wires they can get damaged and also the ends which connect into the distributor cap and spark plugs can get loose and not make a good enough connection for proper firing.
so check each cylinder for spark and then timing, i wanna check timing and make sure its right but i dont have a timing light, can i get the timing somewhat right without it?
 

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so check each cylinder for spark and then timing, i wanna check timing and make sure its right but i dont have a timing light, can i get the timing somewhat right without it?
In my opinion, if you own a vehicle with a distributor, you really aught to own a timing light.

No experience with the one I linked to, but "Draper" is a good brand. It's sort of like the British equivalent of Craftsman.


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Discussion Starter · #39 ·
In my opinion, if you own a vehicle with a distributor, you really aught to own a timing light.

No experience with the one I linked to, but "Draper" is a good brand. It's sort of like the British equivalent of Craftsman.


Sent from my F-150 using Tapatalk
i ordered one but in the mean time i started the truck and unplugged each sparkplug wire to see if some cylinders were dead, 3 and 7 seemed to be getting no spark, u can normally arch them to see the idle change and 3 and 7 wasnt arching, i changed plug wires on both the cylinders with one that i knew worked and they still seemed to get no spark, could one of the points on the distributor be messed up?
 

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Discussion Starter · #40 ·
i ordered one but in the mean time i started the truck and unplugged each sparkplug wire to see if some cylinders were dead, 3 and 7 seemed to be getting no spark, u can normally arch them to see the idle change and 3 and 7 wasnt arching, i changed plug wires on both the cylinders with one that i knew worked and they still seemed to get no spark, could one of the points on the distributor be messed up?
Scratch that i cleaned off distrubotor points and they are firing now
 
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