injectors - how to tell?

[kraiye]

hi all, just got couple questions...

firstly, i got a set of injectors layin round but have absolutely no idea what impedance or size they are. does anyone know how to tell or how it can be worked out?

secondly, what are the specs of the stock injectors i'd find in my ek1/d16y4?

cheers
:)

[joyride]

pics or description would help.

[barefootbonzai]

i believe stock is 240cc.

[kraiye]

i believe stock is 240cc.
do u know what impedance they are?


pics or description would help.
wow! u can tell just by lookin at em??? i thought i'd have to do tests or something. i'll take em to a specialist if i have to but i'd rather do it myself if i can learn something from it. will c if i can grab sum pics for ya.

[tinkerbell]

they *should* be high impedence,

use a multi-meter to confirm, abt 10-15 ohms is high

if they are below 5 ohms they are peak and hold and not stock... (unless they are from an early 90's or prior car...)

[kraiye]

hmm cant get pics. my ex-g/f ended up with the camera and my phone just wont get close enough to show any real detail :(
i'll just have to get someone else to check em out

thanks for the info re: stock injectors. will come in handy when upgrading :):thumbsup:

[joyride]

if you upgrade the injectors its a good idea to upgrade the fuel pump also.

[tinkerbell]

if you upgrade the injectors its a good idea to upgrade the fuel pump also.

why? higher flowing injectors will place less stress on the pump. :confused:

[kraiye]

they're for a small turbo install (bout 6-8psi) and i've been informed the stock pump will be ok.
which brings me to another question: is it worthwhile putting the malpasi regulator on? or is the stock regulator ok for such a job?

[tinkerbell]

is it worthwhile putting the malpasi regulator on? or is the stock regulator ok for such a job?

depends what else you are tuning it with doesnt it...

[joyride]

why? higher flowing injectors will place less stress on the pump. :confused:i would assume you need a bigger pump to bring more fuel to the larger injectors. i mean, wouldnt it defeat the prupose of using the same pump if the same amount of fuel is going to be supplied to the larger injectors? :confused:

[kraiye]

not necesarily the amount of fuel but the amount of pressure. if the original pump is easily capable of supplying appropriate pressure for stock then i lil extra fuel should be ok.
the pump supplies pressurised fuel to the regulator which allows the right amount of fuel through (so i believe) but yeah...

[tinkerbell]

same pump does NOT equal same amount of fuel.

the amount of fuel is determined by injector size and fuel pressure regulator release point.

plus the ECU in telling the injector how long to stay open for...

if you make the injector bigger, it needs to stay OPEN for LESS time to supply the smae amount of fuel...

so the strain on the fuel pump is less...

this is all assuming that the engine is the same before/after...

if you are adding larger injectors AND a turbo, upgrading the fuel pump might be a good idea...

if you wann learn a bit more about injectors and their relationship to fuel pressure, see here:

http://www.rceng.com/technical.htm

[poid]

if you are using an ECU (ie not something like an FMU, VAFC etc) to tune then you wont need to change the fuel pump or regulator. Keep it simple, injectors + ECU (and a good tuner!) is all you'll need for the fuel management side of things.

[joyride]

i see i see

[kraiye]

hmm... i got unichip. hopefully will suffice. i'd prefer to change as little as i can if i can get away with it (reasonably comfortably anyway)

[tinkerbell]

as long as your tuner knows unichip, you should be OK, it is not ideal, but should suffice...

[poid]

you'll get away with Unichip, but i'll bet you will upgrade that down the road (almost everyone who gets it goes to a proper ECU solution later on)

[spardikis]

not necesarily the amount of fuel but the amount of pressure. if the original pump is easily capable of supplying appropriate pressure for stock then i lil extra fuel should be ok.
the pump supplies pressurised fuel to the regulator which allows the right amount of fuel through (so i believe) but yeah...



correct!

[kraiye]

thansk guys :)
i'm sure i will upgrade the ecu later on but cash is an issue now and the chip came with kit i got 2nd hand so not too worried bout it now
i'm sure i'll also upgrade turbo, zost and motor down the track too ;)