Siemens Injectors ~ Where from and are 660cc to big?
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PassionFord Post Troll
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From: Kent
Siemens Injectors ~ Where from and are 660cc to big?
Anyone know where to get them from?
Not sure exactly what i need yet, but basically a high impendence (sp) siemens injector to replace my bosch dark green 803's which are still brand new and up for sale.
The company that will be mapping the car are recommending a 660cc Siemens high impendence injector.
is 660cc too high a flow for a 2.1 zvh?
They seem to think it will be fine as i will be running closed loop lambda control.
Matt.
Not sure exactly what i need yet, but basically a high impendence (sp) siemens injector to replace my bosch dark green 803's which are still brand new and up for sale.
The company that will be mapping the car are recommending a 660cc Siemens high impendence injector.
is 660cc too high a flow for a 2.1 zvh?
They seem to think it will be fine as i will be running closed loop lambda control.
Matt.
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Seems just about right. And if you fear the pulsewidths are getting too short on idle, you can always take the pressure down to the efi's standard 2.5bar. Makes the life much easier for the fuel pump as well.
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PassionFord Post Troll
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From: Kent
Fuel pressure is currently set at standard. Not too sure what that is but its a standard Fiesta RS Turbo pressure reg.
What sort of money would a set of these Siemens injectors cost?
What sort of money would a set of these Siemens injectors cost?
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PassionFord Post Troll
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From: Kent
Originally Posted by Google search
Peak and Hold Driver/Injectors
These type of injectors and drivers may also be called current sensing or current limiting. They are more expensive and complex than saturated circuit drivers, and are not generally used with domestic production ECUs. They are primarily used in aftermarket high performance systems.
Most high flow injectors are low resistance (2-5 ohms) and use a peak and hold driver to activate them. The Peak current is the amount required to quickly jolt the injector open, and then the lower Hold current rating is used to keep it open for as long as the ECU commands. These require the extra kick from the higher current to keep the opening and closing time of the injector stable at the higher fuel flow rate.
With this type of driver, 12 volts is still delivered to the injector, but due to the its low resistance, the current in the driver circuit is high. How high? Using Ohms’s Law we can calculate the current rating (12v/2 ohms = 6 amps). This is substantial current flow and a Saturated Injector cannot handle it.
The drivers also come in two values; 4 amp peak/1 amp hold, and 2 amp peak/0.5 amp hold.. Even though 6 amps may be available to operate the injector, the maximum it is allowed to reach is 2 or 4 amps, depending on the driver’s current limit. Note that the MSD PN 2014 (72 lb/hr, 2 ohm) and PN 2015 (96 lb/hr, 2 ohm) injectors require a 4/1 amp driver.
These type of injectors and drivers may also be called current sensing or current limiting. They are more expensive and complex than saturated circuit drivers, and are not generally used with domestic production ECUs. They are primarily used in aftermarket high performance systems.
Most high flow injectors are low resistance (2-5 ohms) and use a peak and hold driver to activate them. The Peak current is the amount required to quickly jolt the injector open, and then the lower Hold current rating is used to keep it open for as long as the ECU commands. These require the extra kick from the higher current to keep the opening and closing time of the injector stable at the higher fuel flow rate.
With this type of driver, 12 volts is still delivered to the injector, but due to the its low resistance, the current in the driver circuit is high. How high? Using Ohms’s Law we can calculate the current rating (12v/2 ohms = 6 amps). This is substantial current flow and a Saturated Injector cannot handle it.
The drivers also come in two values; 4 amp peak/1 amp hold, and 2 amp peak/0.5 amp hold.. Even though 6 amps may be available to operate the injector, the maximum it is allowed to reach is 2 or 4 amps, depending on the driver’s current limit. Note that the MSD PN 2014 (72 lb/hr, 2 ohm) and PN 2015 (96 lb/hr, 2 ohm) injectors require a 4/1 amp driver.
Hi Karl,
I just did a quick search on google to find out what Peak and Hold injectors are.
It says they are low impendence (i.e about 2 ohms)
My ecu (DTA P8) must run high impendence (5 ohms or more)
Any further advise would be much appreciated.
Matt.
Norris Motorsport
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Typically peak and hold are in the 2.5 to 4 ohm range. If you ecu is compatible with these type of injectors then I suggest you use them, as you'll struggle to get a saturated type 660cc down to a stable low enough on time at idle. (i.e. you'll need around 1.5ms @ idle and will struggle with a saturated 660cc to attain this.)
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Norris Motorsport
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To my knowldege the minimum stable on time for a pintle style (though siemens is a derivative of this) saturated inj is around 1.5ms. Only the lucas disc type saturated can get down that low.
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From what i undersatnad low impendence are slow and high impendence are fast as a rule of thumb.
I may have my wires crossed there though.
Thanks Karl, i best give the ECU company a call and see what they say.
I believe i can use low impendence injectors but i will need to install ballast resistors in the earth (ECU) wire of each injector.
Matt.
I may have my wires crossed there though.
Thanks Karl, i best give the ECU company a call and see what they say.
I believe i can use low impendence injectors but i will need to install ballast resistors in the earth (ECU) wire of each injector.
Matt.
Norris Motorsport
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From: Derbyshire
zvhturbo, no you've got that the wrong way round.
A peak and hold type (i.e. low impedance) runs with much greater current (i.e. up to 6 amps) due to the low impednace. This gives the solenoid are quicker and more accurate response but does of course require the ecu to have the inj driver ability to provide the higher current level.
(A saturated inj (i.e. 16 ohm) operates with less than 1 amp current)
A peak and hold type (i.e. low impedance) runs with much greater current (i.e. up to 6 amps) due to the low impednace. This gives the solenoid are quicker and more accurate response but does of course require the ecu to have the inj driver ability to provide the higher current level.
(A saturated inj (i.e. 16 ohm) operates with less than 1 amp current)
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From: Finland
Originally Posted by zvhturbo
I believe i can use low impendence injectors but i will need to install ballast resistors in the earth (ECU) wire of each injector.
Karl: You being the CVH master, how much of a difference does the different spray patterns of different type of injectors do?
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From: Kent
Originally Posted by JesseT
Originally Posted by zvhturbo
I believe i can use low impendence injectors but i will need to install ballast resistors in the earth (ECU) wire of each injector.
Karl: You being the CVH master, how much of a difference does the different spray patterns of different type of injectors do?
I've just spoke with DTA Engine Management and the Tuner and they both say i need the high impndence Siemens injectors and that they have a really good idle.
I will have to go with there recommendations as they both said the same thing for my engine and ECU set up.
Matt.
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