What is the difference between "Peak and Hold" vs "Saturated" injectors!

1.Whats the difference?

2.What do these terms mean?

3.Is one better than the other?

 

http://www.msdignition.com/fuel_3.htm

 

Thanx!

 

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

 

What type of injectors are on a LS and a B16! Am I supposed to have an resistor box? B18b in 92 Hatch Si

 

The injectors must match the ecu. You have a 92 hatch with a b18b then you would not use a resistor box.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sack Master &raquo;</TD></TR><TR><TD CLASS="quote">The injectors must match the ecu. You have a 92 hatch with a b18b then you would not use a resistor box.</TD></TR></TABLE>

They don't have to match the ecu, you can use peak and hold as long as you're using a resistor box, or use saturated without a resistor box. The ecu sends the same type of signal to the injectors.

 

My ECU is a P75 and I am currently running injectors off my old B16 and have a set of OBD-1 JDM H22 injectors that I want to use! So do I need a resistor box?

 

I don't remember if H22 injectors are saturated or peak and hold. Most injectors 92 and up are saturated and don't need the resistor box, but I think the prelude may be an exception and might be peak and hold. Don't hold me to that though. Your car doesn't have an injector resistor box normally so it would probably be easiest to get some OBD1 saturated injectors, but the ECU doesn't care which you use, but you must use a box with peak and hold, none with saturated.

 

I believe the H22 are peak and hold as well.

 

Thanx, I am seaching now!

 

the h22a jdm ones are peak and hold, its just the usdm models that are saturated

 

Thanx