Injector size and how many - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

EA Turbo Clone · 11-02-2003, 15:07

I am putting in an aftermarket ECU, and weighing up injectors/fuel pumps, i was thinking of running twin standard pumps, and the standard size injectors, with staged injectors as well which would be run off the second pump.

How much can you get out of the standard injectors with a regulator? from my calculations 2 extra into the throttle body should be right for 10psi boost. Am i correct?

not ford · 11-02-2003, 20:24

Need to know how much flywheel hp you are making and how much you want to make (realistically).

Also 6 "775" blue top injectors at 60psi base pressure will ONLY support 300fwhp. These are 24lb, EA ones are 19lbs.

For 400fwhp you will need ~45lb injectors minimum. The motec does sequiential injection so it can handle big injectors well.

gm dstroya · 11-03-2003, 00:58

5cc will equals 1 hp so 550cc will equal 110hp per cylinder,

so six of the 550cc injectors (one per cylinder) will equal 660hp supported, but you only wanna run ur injectors at 75% duty cycle as maximum for a saftey margin, so that means the 550cc injectors will safley support 82.5hp. over 6 cylinders thats 495hp safley.

to support 600 hp you'd need six 675cc injectors.

as for fuel pumps, its hard to go past the bosch motor sports items the 0444 pump will handle 500rwhp safely.

cheers.joe.

ebxr8240 · 11-03-2003, 02:46

Find out if low impedance injectors are not that much dearer? not sure.But aftermarket can be setup to run them.[L.I]They are better with higher flow rates.. But again maybe too expensive... Most new ecu's can be set to run sequential, it's just a matter of wiring them as in std loom they are batch..joined...

EA Turbo Clone · 11-03-2003, 04:29

I am going to run staged injection, so i will have my 6 standard injectors plus another ?? for the extra fuel, what i am not sure of is how much the standard ford injectors flow, i don't see the point in buying new injectors when i have about 18 standard EF injectors sitting there. and i figure the standard 6 plus another 6 should be more than ample, as i doubt that the engine will see over 450hp, as the turbo only flows 450hp.

Also does anyone know the impedance of the standard ford injectors? So that i can work out the load on the ECU.

I have had a change of plans and decided to go with the Wolf3D vers 4, due to price, and it does everything i need. plus the fact that it is in 125rpm increments and that i dont need a laptop to tune it.

EA Turbo Clone · 11-03-2003, 04:30

Oh and i forgot to mention, i don't have a wiring loom on my engine i am going to make a new loom to suit what i want.

ebxr8240 · 11-03-2003, 04:52

High impedance 12 to 16 ohm..

not ford · 11-03-2003, 15:12

As ebxr8240 said the std Ef injectors are high impedance, somewhere from 12 to 16 ohms. They apparently flow 24lbs.
If you are an electrical engineer you should own a multimeter, check the resistance between the terminals.

Walkinshaw · 11-03-2003, 16:56

why couldnt you run a second fuel rail and use low impedence injectors, wire two of them in series and hook it back to the standard ECU.

However it seems more mucking arround than using one set of high flow injectors.

EA Turbo Clone · 11-05-2003, 01:17

Yes i own a multimetre, but that measures resistance not impedence. and i am not interested in running the standard ECU, you spend just as much money getting a chip put on one as you do buying an aftermarket computer, and the plus is with the aftermarket computer you can change the software as you want to, you don't have to go get another custom chip done to suit more upgrades.

The reason i want to run staged injection is because i have heaps of these injectors sitting around, why waste $600+ on buying low impedence injectors. Also i am under the belief that i should be able to get the car more accurately tuned with staged injection because you are still only using the 6 standard injectors to run the idle and cruise mixtures, and also it enables me easily run two fuel pumps and fuel lines.

I think when they say 24lb injectors they are refering to the fuel pressure behind the injector, you can easily run them at 40lb just by changing the regulator, which just about any supercharger kit has included with them.