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Megasquirt MS3X with 8 Injectors on 13B

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Old Dec 29, 2015 | 03:24 PM
  #1  
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MS3X with 8 Injectors on 13B

Hello

Does anybody know the wiring of 8 Injectors on a 13B engine with MS3X.
I want to use:
2 x primarys front rotor
2 x primarys rear rotor
2 x secondarys front rotor
2 x secondarys rear rotor

with staged injection to control primarys and secondarys.

Injectors are high impendance.
Is it possible to wire 2 identical injectors parallel together to one Injector output?

thanks in advance
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Old Dec 29, 2015 | 07:41 PM
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i think that ken or james told me a long time ago that you can use 2 hi omhs injectors per channel.
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Old Jan 1, 2016 | 08:06 AM
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Should work with injectors of high enough impedance. However, why would you do it this way? Why not get 4 properly sized injectors and avoid the extra complication?
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Old Jan 1, 2016 | 06:00 PM
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he's probably running methanol as fuel, i have seen 13b motors running on 10 2200cc injectors when they are running methanol for fuel and a lot of boost.
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Old Jan 2, 2016 | 02:49 AM
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yes thats right. we want to use methanol and run 8 of 2000cc injectors (like the 0280158821 -> 9,1Ohms)
Is there another way to wire them?
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Old Jan 2, 2016 | 07:31 AM
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in parallel?
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Old Jan 2, 2016 | 10:08 AM
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You can also use external low impedance drivers to allow multiples of injectors on each channel. One of these, for example:
Peak&Hold Injector Driver Board v2.0.1
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Old Jan 2, 2016 | 12:24 PM
  #8  
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thanks for the replys.
I dont wan to use another board for controlling the injectors.
In the hardware manual for the MS3XV357 there is written, that the injector dirvers on the MS3X are limited to 5 Amps each. So two 9,1Ohms Injectors on one driver should work or am i wrong?
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Old Jan 2, 2016 | 12:38 PM
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low impedence have a higher initial trigger threshold of about 4amps then down to less than 2 before closing again.

high impedence injectors generally run less than 2 amps and could be run in pairs off a single circuit.
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Old Jan 3, 2016 | 09:59 AM
  #10  
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Well, two 9 ohm injectors in parallel is 4.5 ohms.

Ohms law I = V / R

I = 14 / 4.5
I= 3.11

So yes, should work.

And yes, I realise that's for a resistive load not an inductive load. Numbers are close enough. Inductive load will have an initial spike as the inductor charges, then settle to the value of a resistive load.
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Old Jan 7, 2016 | 08:59 AM
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be sure to measure your dead time when wired up that way. It'll likely change depending on what the circuit is driving.
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Old Jan 7, 2016 | 04:17 PM
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ken can something be code to use the extra injectors outputs to drive more injectors on a 13b.
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Old Jan 8, 2016 | 11:29 PM
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Originally Posted by elturbonitroso
ken can something be code to use the extra injectors outputs to drive more injectors on a 13b.
Already is, you can run sequential on the ms3x outs and then batch for the second stage on the ms3 outs.
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Old Jan 9, 2016 | 09:13 AM
  #14  
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i mean the output on the ms3x card something like a+e and b+f primaries and c+g and d+h secondaries.
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Old Jan 11, 2016 | 05:49 PM
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Originally Posted by elturbonitroso
i mean the output on the ms3x card something like a+e and b+f primaries and c+g and d+h secondaries.
Could be if more than just 1 person will use it :-)
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Old Jan 12, 2016 | 06:03 PM
  #16  
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that would be a other nice feature available for the very hi horsepower
cars.
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Old Jan 20, 2016 | 11:47 AM
  #17  
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Originally Posted by muythaibxr
Could be if more than just 1 person will use it :-)
Ill use it this is going ms3x
Attached Thumbnails MS3X with 8 Injectors on 13B-rx7-race-car.jpg   MS3X with 8 Injectors on 13B-rx7-race-engine.jpg  
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Old Jan 20, 2016 | 11:52 AM
  #18  
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Originally Posted by RotaryEvolution
low impedence have a higher initial trigger threshold of about 4amps then down to less than 2 before closing again.

high impedence injectors generally run less than 2 amps and could be run in pairs off a single circuit.
ben, thanks for the info!
i was thinking of running 2 injectors for water/meth off the trailing signal wires, it would be easy and scale the injectors of water to what the fuel is doing in regards to airflow.(more air-more fuel more water)
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