yelw02GT

my next round of mods is intake manifold, injectors and a fuel pump, my question is can i instal all 3 at my house and be able to start it up and drive up to my tuners shop? the car already has a tune on it, but my main concern is the injectors ill be going from stock injectors to either 24 or 30 #..it doesnt have to run nice just enough to take me 25 minutes up the highway, thanks for any advice

Stevecooper

Easy solution... don't install larger injectors in a car that does not need them.

yelw02GT

k well if im not mistaken, you might need injectors when your duty cycle is damn near maxed out and your plan on spraying in the near future..just a thought, thanks for the valueable info, or even asking why im doing what im doing, thanks again

tws1098

easy now lol...I think a lot of people on here assume they need bigger injectors for this or that, and it's come up a good bit lately (i asked about it once myself) so I'm thinking that was the reason for the "quick" response. To get the car to the shop you should be fine if you aren't hammering on the car. And I may be wrong (someone correct me if i am) but i think it will run rich anyway so it shouldnt be a big deal. Just keep your rpms down and either way you should be fine for a short drive.

Stevecooper

Okie dokie, are you going to run a wet or dry nitrous system?

How do you know (think) that your injectors are reaching their maximum duty cycle?

Lastly why would I ask what you are doing, I would assume you to be the one that provides that information when you ask a question regarding injectors...

forcefeed

why do you feel you need larger injectors?? if you are gonna spray in the future i would recommend a wet shot anyways, this way you are adding fuel and nos into the intake and you have no need to worry about injector size.

pcs

bigger injectors for yellow gt would not necessarily be a bad thing. given the mods he has. a 24lbs inj running at 80% duty cycle ,recommended from ford,with a bsfc of .5 is rated for about 300 hp at the flywheel. a 19lbs inj would be running at almost 100% duty cycle to make that power. given the mods he has without the NOS, it would not be a bad investment for his car. i would say just get the 30lbs ones because you will always want more power, say ported heads to complement those cams. good luck yellow.

Stevecooper

Their are many people making 300rwhp (not flywheel) on stock 19's so this information is wrong. Also if he is going to run a wet nitrous kit the injectors are irrelevant.

I guess we should wait and see what his plans are for a nitrous kit and other supporting mods.

pcs

NOT WRONG, that is straight from ford racing catalog. u know, from the people who make our car. also if you read the message its states what ford recommends not what is fact, not made up info, not hear say, or what some guy claims on a forum to know. now have people made more power that what ford recommends for the injectors yes. i also stated "given the mods W/O nos." so i do know that with a wet system it should be irrelevant. you should probably read the message entirely before YOU state Wrong info. but thx for caring.
and finally a standard eqn' for calculating inj size base on flywheel hp
(flywheel hp * Bsfc)/(#cylinders*% duty cycle)
bsfc =.5 #cyclinder= you should know that 80%duty cycle recommend from Ford.

myslow2002gt

19lb inj will support:

337 at 45psi with a BSFC of .45
304 at 45psi with a BSFC of .50
276 at 45psi with a BSFC of .55



An N/A 4.6L 2V generally runs at 40psi with a BSFC hovering around .45-.47 so it will handle a little more power than what's been stated in this thread.