Some fuel injector questions

[1993MTXSHO]

What is the difference between a high and low impedance injector and what are the benefits of both? Also to make around 400hp what size injector is needed and do the fuel rails have to be modified at all to make that injector fit? Also will a 155lph fuel pump work with 400 hp?

Edit: I did search this and im still confused

 

[HotRodKid]

low impedance injectors run at a straight 12 volts, just like a light bulb they are either of or on,

high impedance injectors use 12 volts to open, then drop to a lower voltage to keep them open, the low tech way some do this is with a resistor in the power wire. it allows 12 volts to flow thru to open the injector, then the resister bumps the voltage down to a single digit #. this allows the injector to open fast, but not build up much heat

some cars can run H.I. injectors using a resistor pack, some need a injector controller box to run them,and usualy when you get to about 60# of injector flow, the injecors are H.I. style

to run 400hp, get the 48# injectors that have been modded to fit the stock rails (forget who on here sells them) also get the 255 pump and an aftermarket FPR and youll be good to go, its the setup thats on somedude_001's turbo sho and it works great

 

[1993MTXSHO]

155 wont cut it huh? Im trying to keep cost down so I don't have to use the aftermarket regular.

 

[SASHO91]

Josh sells the modified injectors that fit stock rails (as wel as modified rails) in 48lb units. (edit: but you'll need to tune for these)

As stated, you'll need a bigger pump. A 190lph, IMHO, and you wont need a FPR.
The "dirty" way to do it, as this is going to be F/I, would get a Rising rate FPR (about 50-75 bucks on ebay). Tim used one of these on his turbo car for years.. worked "fine".

EDIT: a quote by Tim
http://www.shoforum.com/showpost.php?p=644750&postcount=6

 

[HotRodKid]

another fuel pump option, one that a number of the focus and stang guys use, is dual stock pumps

get a second stock 155 pump, mount it to the side of the current stock pump, then use some fuel safe tubing to combine the outlets and run them to the fuel line. might require using the stock power wires as a relay control, and then run new thicker power wires from the battery

 

[SASHO91]

stock FP is 112lph
thats not a bad idea.... but wouldnt boost-a-pump be a better option?

 

[SASHO91]

Also to make around 400hp what size injector is needed

DUDE... WTF are you going to do with your car???? I mean honestly.... you say here, that your shooting for 400hp... but then here - http://www.shoforum.com/showpost.php?p=689984&postcount=11 you state other wise....
So what is it????

 

[john buck]

lmao

 

[1993MTXSHO]

DUDE... WTF are you going to do with your car???? I mean honestly.... you say here, that your shooting for 400hp... but then here - http://www.shoforum.com/showpost.php?p=689984&postcount=11 you state other wise....
So what is it????

im planning for the future, i figure instead of getting stuff that will need to be replaced when going FI I should get the stuff I need now and just be ready. The reason im all over the place all the time is because I can never get a straight answer from my dad as to wtf I can do. Im not shooting for any hp right now im just trying to make sure the stock stuff will work with the 3.3L and if so ill change it when needed, but if a 3.3L with all bolts ons and cams will need higher flow injectors i figure get the stuff that will support the 400hp now rather then get it now and then have to buy it again later ya know what i mean?