Need help with fuel injectors

I have a 347 stroker with a bbk fenderwell air intake, bbk 75mm throttle body, GT40 upper and lower intake, GT40 heads, and e303 cam. I’m currently running 19lb injectors, do I need 24 or will 19 work with what I have. Car is also tuned with a chip.
 
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Ford put 24s in the Cobra that had the same heads and intake as your 347. So you should definitely upgrade them to at least 24s. If you think you might put better heads and intake on it in the future consider 30s so you don’t have to buy parts twice.
 
Ford put 24s in the Cobra that had the same heads and intake as your 347. So you should definitely upgrade them to at least 24s. If you think you might put better heads and intake on it in the future consider 30s so you don’t have to buy parts twice.
Can an adjustable fuel pressure regulator be used to create more pressue? To make the 19's flow like 24's?
 
19s would be at their max even if you bumped the pressure up. Ford used 24lbs in 5.0s in the cobra....and 30lbs in the supercharged turbo coupe 3.8L. 30s would be a better fit for your combo power level, but 24lbs would work. 19lbs are a stretch.
 
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Will 19's not work at all? Just bought them not even a month ago brand new, would really really hate to get rid of injectors with not even 20 miles on them.
they will 'work' if you just slep around idle'n to about 2k rpms after that they just run out of steam, 24's are about the limit when you get to max rpms.
 
Okay so 24lb injectors final. Will the stock fuel pump still work with them?
Fuel pump doesn’t care what size the injector is, so it’ll work. If you just put bigger injectors in without changing anything the car will run rich though.

Did you build the 347 or was it in the car when you bought it?
 
Look, if you want to run the stock fuel pump you can but it's not recommended, you start updating stuff you need to up date other stuff, do you put on shoes that are too small because you like them or they are in style?
If you are going to build a ride build it right.
Just because you can does not mean you should.
 
If you take a car that runs well with a small injector, and then install a larger one without either doing something in the tune for it, or tricking it with a maf calibrated for it, it’ll run richer.
Ah okay, I just sucked it up and went ahead and bought the 24’s and the bbk mass air meter that’s calibrated for them. Once those both get here i’ll take my chip back out and have it retuned for both of those.
 
You could probably drive around fine on 19's but at the end of a long WOT pull you might be running out of fuel. This is where you can sorta band-aid it with a adjustable fuel pressure regulator and add a few more PSI.

Really the right way to do this is a larger injector. If this is your final combo, 24's are fine. The stock pump should be adequate for a GT40 headed N/A combo. If you have some money to burn, you can upgrade to a 110lph or 155lph pump as that's all you'd need for your current combo.

If you do go to the 24's you'll need some way to adjust for this in the tune.
 
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Ah okay, I just sucked it up and went ahead and bought the 24’s and the bbk mass air meter that’s calibrated for them. Once those both get here i’ll take my chip back out and have it retuned for both of those.

Doesn't really make sense to get a calibrated MAF and then burn a chip/tune for the 24's. You kinda want to do one or the other, but not both.
 
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