B->D series injectors

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SolPWR

Senior Member
are the B series injectors interchangable with the D series injectors?
 
Originally posted by pills_PMD@Oct 27 2003, 09:15 PM
yes. as long as they are the same obd

they are both 240 cc

ITR are 270cc.

EDIT: This may be JDM only.....not sure about USDM.
 
Originally posted by gocivicls@Nov 2 2003, 05:32 PM
I mesured the resistance. The ITR injector had a couple of ohms higher than my factory LS ones.

that, i don't know.

why does the 92-96 prelude have 345cc injectors?


uhh, why is the sky blue? it just so happens to come with them from honda. in 97, they realized that they didn't need all that fuel, so they cut them down a little bit to save money most likely

and what is the difference between saturated and peak and hold?


resistance, and what kind of ecu they go with. Generally, peak/hold injectors require a resistor box to lower the impedence that the ecu sees so it doesn't fry it.

saturated do not. they are already low impedence, and are said to be better/easier to control, and flow better (though i have no proof of this)

is there any stock cars that has like 300-350 that would fit into a D series?

not that i know of.

the 2nd gen NA rx-7 injectors are said to be in the low 300s range and fit honda rails, but i don't have any hard evidence of this.
 
I doubted the difference of my LS vs. ITR injectors until I mesured the resistance. The ITR injector had a couple of ohms higher than my factory LS ones.

Why is there a difference if the two are the same (240 cc)??????


Did you measure them while they were installed in a car? Temperature difference is most likely the reason that they are a little bit different. If you look at a service manual for a car, they will tell you the specified resistence for the injector at a certain temperature. Just a guess.
 
Originally posted by pissedoffsol@Nov 3 2003, 06:17 AM

and what is the difference between saturated and peak and hold?


resistance, and what kind of ecu they go with. Generally, peak/hold injectors require a resistor box to lower the impedence that the ecu sees so it doesn't fry it.

saturated do not. they are already low impedence, and are said to be better/easier to control, and flow better (though i have no proof of this)


great info from the aem boards-

"Some of you may be wondering what the difference is between high and low impedance injectors. High impedance injectors are used with Saturated Drivers. Low impedance injectors are used with Peak and Hold Drivers or with Saturated drivers when used in conjuction with a ballast resistor (resistor box). The following, taken from SAE J1832 Nov 1989 - Gasoline Fuel Injector, defines each method and also lists the advantages and disadvantages to each.
SA

Injector Driver—An electronic circuit that supplies voltage pulses to an electromagnetic fuel injector for a precise increment of time and at a given repetition rate. The accuracy of these pulses and their repetition is
normally ±0.001 ms. The peak-hold driver and the saturated driver are most commonly used by the industry for vehicle applications.

PEAK-HOLD DRIVER—A driver that uses two levels of current to operate the injector. The driver circuit applies battery voltage to the injector until a predetermined current level is reached. The current is then reduced and held at a lower level for the duration of the PW. This type of driver is normally used with injectors having low resistance coils (typically around 2 ohm). The accuracy of the driver peak current level (Ip) and the hold current level (Ih) is held to ±0.50%.

Advantages—The high peak current minimizes OT response and the low hold current minimizes CT response. This method of control results in an increased linear range of injector operation.

Disadvantages—Heat is primarily dissipated at the driver. Circuitry is more complex than that of the saturated driver.


SATURATED DRIVER—A power transistor driver that turns fully on for the entire duration of the injector PW. This type of driver is used with injectors having high resistance coils (typically 12 to 16 ohm) or with
injectors having low resistance coils in combination with a ballast resistor.

Advantages—Heat is primarily dissipated through the injector or ballast resistor and not at the driver circuit. Circuitry is simplified compared to the peak-hold driver.

Disadvantages—The inherently slower dynamic response of this system decreases the injector’s usable flow range. The Q of an injector used with this type of circuit is more duty cycle sensitive due to heat dissipation considerations. This driver’s inductive suppression, which may be resistance, capacitance or zener, significantly affects the injector’s Qd rates due to variations in the circuit’s current decay rate. This decay results in a change of the injector’s closing time."
 
Originally posted by 5genracer@Nov 5 2003, 04:33 PM

I doubted the difference of my LS vs. ITR injectors until I mesured the resistance. The ITR injector had a couple of ohms higher than my factory LS ones.

Why is there a difference if the two are the same (240 cc)??????


Did you measure them while they were installed in a car? Temperature difference is most likely the reason that they are a little bit different. If you look at a service manual for a car, they will tell you the specified resistence for the injector at a certain temperature. Just a guess.

Good theory, But both injectors measured cool, room temp.
 
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