i was curious to know what injector size came stock on the 4.6

also what would i need to run a slightly bigger injector MAF,fuel pump, tune what?

help greatly appreciated

 

19lb injectors came on the stock mustangs if im not mistaken.

And i don't get ur 2nd question??...

 

99-02 19lbs, late 02-04 21lbs.

 

on the 2nd question unless you have a high HP n/a motor or a supercharger you dont need any of that, ive noticed around my town everyone asks me when im going to do bigger injectors and a fuel pump..like im driving a cummins or something.

 

+1, Ford went to the slightly larger 21lb/h injectors in 2002 only because the 19lb/h units were running at somewhat high duty cycles (90+%) at full load and WOT.

It's easy to determine if you need larger injectors--just get a wideband O2 system and log AFR and fuel pressure over some WOT runs. If fuel pressure holds as it should and you see significant leaning at higher RPMs and WOT then the injectors are maxing out (this won't happen with a properly tuned n/a PI engine)--if not then higher capacity injectors will no add a thing.

Also while we are on this topic, the stock 80mm MAF is good to 425HP; this is from the latest FRPP catalog's Injector and MAF tech notes:

 

thanks- you guys couldnt of said it better i was just curious if it added extra hp or anything along those lines but obviously not lol

 

Why do all the redneck Chevy guys always ask about injectors? Are Chevy's massively under fueled or something?

 

why would you think adding bigger fuel injectors would give you horsepower?

you need more air into your combustion chambers for any additional fuel to be helpful. adding more fuel without adding more air makes you run rich, which will decrease power not add power. horsepower isnt based off how much fuel you can spray into your motor.