Performance Injectors

[smufguy]

I have been nosing around the 360cc, 450cc and 550cc injectors and seems like people have been saying different view points about them.

I was talking to one my managers at Work who also builds custom parts and turbo for any type of VW. i was asking him about this and he let me know of their duty cycle.

I came to a conclusion that the increased cc injectors dont seem to working their best due to the fact that they are operating at our stock injector duty cycles and not their duty cycle.

I dont know what the hell the Injector resistor box on our cars does, but seems like they have something to do with it if they control our stock injector duty cycles.

Duty cycle is how many times the injector pulses to let fuel in and how much volume (lb) of fuel in according to the A/F ratio calculated by the ECU.


SO my question is, if we get a 310cc inejctor off a H22, dont we need the H22 injector box? I dont know of any other car like a DSM or the Supras using an Injector box, but if they do, i guess it might be a way to solve the problem.



SEAN:: Do you know what the injector box does dude?

[smufguy]

bumpy bumpy

[BootMachine]

I dont think so!

I dont know for sure but we can just say injectors run off 12 volts. Works for me.

Now bare with me I'm not an electrical expert at all but I know a little about tuning AF mix!

If the injectors all work off 12V just get the biggest ones that will fit. WHY? The dudy cycle is controlled by memory in the ECU based on information from the other sensors. To alter these pulses or the DUTY CYCLES you need to tune the ECU. You will need a VAFC, or SAFC (in non-v-tek engines) or you can go Hondata. Basically all they do is let you tune the ECU's pulses to the injectors.

NOW....what you gotta do is know what the hell you are tuning.

You need to monitor the AF mix. Dont get a stupid bouncy fancy AF meter...get an "exhaust temp sensor"

Exhaust temp and AF mix is directly related and linear. Lean mix...temp goes way up...rich..temp goes down.

You need to take a reading from the stock mixture (assuming its still the way honda set it) so you know what the right mix is or the right temp.....and then tune away trying to keep the temp perfect through the entire RPM band. As your rpms increase, you need more pulses to the injectors to add more fuel...or...you go a little lean and temp goes up!

If you have a turbo.....temp goes WAY up and melts the engine before you know what happened!

SO...be careful!

[johnwc723]

not to mention ONE i don think our injectors run 12 volts, why the heck would they, honda would design to use the least voltage possible just to be economical in wiring and stuff so its probably the least amount of voltage required to open tiny solonoid vavle which isnt much

all the injectors run on differeing voltages as far as i know and require different draws and such.

if one is to add higher flow injectors im pretty sure the ECU would notice that each "injection" is adding more power than it intended and thus cut back on the injections thus making higher flow injectors useless?
i dunno thats what i think

[smufguy]

hmmmm so u guys think the injector pulse runs off the ECU based on the A/F ratio. We can always get the Wideband O2 sensor to monitor the A/F ratio more accurately.

So no one knows what the injector box does?

[johnwc723]

i think the only way to get high flows to work to really give you what you are looking for would be to totally re-work the tables in the ecu, but if you were to do this you wouldnt even need hi flow in the first place..?

[smufguy]

basically, i just wanted to understand what controls the duty cycles and what the injector box does and how they are related to each other when it comes to this. thats why.

[BootMachine]

not to mention ONE i don think our injectors run 12 volts, why the heck would they, honda would design to use the least voltage possible just to be economical in wiring and stuff so its probably the least amount of voltage required to open tiny solonoid vavle which isnt much

all the injectors run on differeing voltages as far as i know and require different draws and such.

if one is to add higher flow injectors im pretty sure the ECU would notice that each "injection" is adding more power than it intended and thus cut back on the injections thus making higher flow injectors useless?
i dunno thats what i think

no....injectors are fired using pulse width moulation....power is on...power is off. Same power goes to them each time.....want more fuel? Hold the power on longer!

And adding high flow injectors is NOT useless. You will add more fuel to the engine. THAT...is uselss unless you have air to burn with it!

The computer would use the same "fuel maps" for new new injectors however it may compensate a little by noticing a more rich burn. You use high flow injectors when the stock injectors can not supply fuel as fast as the engine needs it.....