resistor box removal

[89T]

Well all I could come up with is a resistor box instalation diagram.

Borrowed from Ghostaccord
http://img3.imageshack.us/img3/9263/resistorboxwiring3.jpg (http://imageshack.us/photo/my-images/3/resistorboxwiring3.jpg/)

So if we were to remove the injector resistor box. We would tie the yellow/black to all the red/blacks right?

http://img220.imageshack.us/img220/7826/phone092.jpg (http://imageshack.us/photo/my-images/220/phone092.jpg/)
right side injector side....
http://img713.imageshack.us/img713/8407/phone093.jpg (http://imageshack.us/photo/my-images/713/phone093.jpg/)

So if a guy would obtain a plug from another injector box, and solder all 5 wires together. A guy could make a jumper plug for plug and play operation.

the reason for the removal would be running obd1 injectors

[cygnus x-1]

As long as the ECU can handle low impedance injectors, a 'resistor box delete jumper' would work perfectly.


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[89T]

I thought obd1 injectors were high impedance and the reason for the resistors were to use low impedance injectors.

[89T]

So by that way of thinking, we could use low or high impedance injectors with the stock ecu right.

[gfrg88]

some obd1 came with resistor boxes i thought :dunno:

[cygnus x-1]

I thought obd1 injectors were high impedance and the reason for the resistors were to use low impedance injectors.

Oh, yeah that could be. I know Honda used both types of injectors but I don't remember what uses what.



So by that way of thinking, we could use low or high impedance injectors with the stock ecu right.

Yes. Low impedance injectors with resistor, or high impedance injectors without.

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[89T]

hmm.

some obd1 came with resistor boxes i thought :dunno:
I did not realize there were obd1 cars that came with the resistor box.



I know Honda used both types of injectors but I don't remember what uses what.

Yes. Low impedance injectors with resistor, or high impedance injectors without.

C|
This would make it the rule of thumb.
low = with
high = without

[A18A]

i remember once making one of those when i had other injectors in the car, i cut off the resistor box & soldered all the wires together lol

[gfrg88]

ecu shouldn't have anything to do with it. It should all depend on injectors being used. correct? or am i wrong.. I've never had to deal with adding/removing resistor boxes on any of my cars :dunno:

[89T]

It seems that the ecu's are all most likely high impedance.. but some use resistors in order to use low impedance injectors.

[89T]

I was trying to beat this horse dead! lol!

Seem's as if we beat it into submition in 10 post's.

[gfrg88]

Any real difference in the low and high impedance???? Teach me please :thumbup:

[A18A]

the ohm ratings? I think that will be the only difference

[Hauntd ca3]

the honda ecu's must have pretty small injector drivers, hence the resistors to reduce the current.
am liking the toyota ones i have, 13ohms = less than 1 amp per injector

[89T]

Thats food for thought. There is another differance between the 2 types of injectors.
Low impeadance injectors are peak and hold type.

High impeadance injectors are saturated type.

[89T]

Peak and Hold:

Peak/hold injectors are low impedence, usually in the 1-4 ohm range. When the ecu calls for fuel to be injected, it sends out voltage via the wire clips until a certain current level is reached (the peak part) (varies by injector size, company). For the duration of 1 pulse width, that current is slightly reduced and held (the hold part).

Advantages of this design:•minimizes the injectors "on" time, resulting in faster response
Disadvantages of this design:•increases coil heat, which can lead to failure over time

--------------------------------------------------------------------------------


Saturated:

Saturated injectors are generally higher impedence than peak and hold, running in about the 10-15 ohms range. Unlike peak/hold, a saturated injector remains "on" for the entire pulse width.

Advantages of this design:•reduces heat
Disadvantages of this design:•slower response time
•can't handel large CC or lb/hr styles due to limitations in its speed.

--------------------------------------------------------------------------------


So, which should I choose?

There are a ton of factors involved in this.
•First, power level. If you're going big, there simply won't be a saturated injector that will support your power level. The largest common saturated injecotrs on the market are 550cc, with 440cc being a common "cap" in saturated size. Most boosted people run peak/hold setups for not only their availibilty, but also their ease of upgrading later on if so desired. simply swap the injectors. no need to re-wire again.
Some of this is no longer true with the availibility of Injector dynamics (ID) or Injector clinic injectors, example..
ID725 - Nominal Flow Rate - 715cc/min

ID850 - Nominal Flow Rate - 885cc/min or 1000cc/min at 100 psi fp.

ID1000 - Nominal Flow Rate - 1015cc/min or 1600cc/min at 100 psi fp.

ID2000 - Nominal Flow Rate - 2225cc/min or 2500+cc/min at 100 psi fp.

*Dynamic flow rates measured at 3 bar (43.5 psi) using VP Racing C16 Gasoline.

So now you can go big. lol!


•How is your car wired? most obd0 civics and some preludes are wired for peak/hold and have a resisitor box already. No point in changing to a saturated. Obd1+2 civics, and most other honda/acura cars after 1992 are all saturated and are not wired with resisitor boxes. Again, if there is an injector availble in your power range for flow of your car's design type, there's little sense to change.
•Price. DSM eclipse/talon 450cc peak and hold injectors fit honda rails and with just a minor modification plug right in. best of all, these can be had for about $50-75 a set of 4 instead of $350+ for a set of aftermarket injectors. Add a $25 resistor box from an obd0 civic/crx, wire it up, and you're good to go in you're saturated car.

[gfrg88]

wow. I vote sticky on that info!!! I never knew the advantages and disadvantages :thumbup:

[89T]

Here is bit more info I found.
http://www.robietherobot.com/storm/fuelinjectorguide.htm

[gfrg88]

Soooo we have peak and hold, right? Which if I'm not a complete dumbass, can do better at higher CCs?? Am i right?

[89T]

Soooo we have peak and hold, right? Which if I'm not a complete dumbass, can do better at higher CCs?? Am i right?

yup! The advantage of peak and hold injectors is the availibility of larger injectors. most domestics run peak and hold. There sizes are shown in #. So 720cc injectors are roughly 72# injectors

[gfrg88]

So why do you want to remove it?? lol.. I'm a little confused :dunno:

[89T]

well, I got a deal on ID1000 injectors and will be running 100psi base fuel pressure. ;)

[89T]

wow. I vote sticky on that info!!! I never knew the advantages and disadvantages :thumbup:

There are no mods that care about that stuff anymore. I can only think of 1 maybe 2 mod's that are even on regular.

Maybe its time for new blood.

[gfrg88]

Jerry for president!!!!! errr mod!! :thumbup:

[gfrg88]

I wanna be a mod for classicprelude :)

[89T]

Jerry for president!!!!! errr mod!! :thumbup:

Lol. No thank you.

[gfrg88]

We definitely need new mods, imo.

[89T]

There are alot of great people like Accordepicenter, Pico, Oldblueaccord, Roodoo2, Snooz.... Man there are just to many well qualified people to list.

[Dynamaxx19]

I got low impedance injectors in my 3rd gen accord lxi 3 door.
I want to put better ones but how big can I go with stock ECU and stock fuel pump.
should I put a aftermarket pressure regulator in to bring rail pressures up?
Does anyone know this part?

[cygnus x-1]

I got low impedance injectors in my 3rd gen accord lxi 3 door.
I want to put better ones but how big can I go with stock ECU and stock fuel pump.
should I put a aftermarket pressure regulator in to bring rail pressures up?
Does anyone know this part?


With a stock ECU, higher flow rate injectors will just make it run badly, because the ECU is tuned to use a specific injector size. To be able to use different sized injectors you really need some sort of tunable ECU, e.g. an OBD1 conversion or aftermarket ECU.

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[Tdurr]

^^^Church.