MS3X and batch fire

General support questions and announcements for MS3. See also MS3 manuals.

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cukali
Experienced MS/Extra'er
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Joined: Tue Jun 08, 2010 8:59 pm

MS3X and batch fire

Post by cukali »

couple quick questions I couldnt find info on in the manuals...

1. If using alternating injection with 2 squirt per rev, what injectors are batched together and when are they fired on a 4cylinder? (using ms3x drivers)
2. If I switch to semi sequential to use the timing table, is the table controlling batch 1 then batch 2 is then fire 180 later?
3. I need to adjust my cam pots on the MS3 board. I have a Nissan CAS from DIY but have it running just using the crank signal for now. Can I use the tooth logger while adjusting the pots and see when they are right or do I have to enable the cam input and just trial and error them?
DeadStiff
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Re: MS3X and batch fire

Post by DeadStiff »

1) 1+3, 2+4
2) yes
3) You have to enable the cam for the ecu to read it. It should run in semi sequential until it sees the cam, in that time you can use the tooth logger to adjust the pots.
MS3+X on 73 Karmann Ghia ignition only with LS2 truck coils firing in sequential, fuel next.
2333(103*70) Type 4 with DTM also sitting in living room just need exhaust.
cukali
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Re: MS3X and batch fire

Post by cukali »

As soon as I set "semi sequential" it stalls. Tried halving the fuel but stalls again. Doubled the fuel and same thing.


What parameters change when switching to semi sequential?

On a 4cyl, batch fire fires two at at time...for semi sequential it does exactly the same thing so what changes?

I tried 1 squirt per cycle simultanious, alternating, and several other options using 2 squirts....almost like the fuel just shuts off.
Matt Cramer
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Re: MS3X and batch fire

Post by Matt Cramer »

Do you have before and after MSQs, and a data log of the stall issue? This will give me more to go on.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
jsmcortina
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Re: MS3X and batch fire

Post by jsmcortina »

cukali wrote:As soon as I set "semi sequential" it stalls.
Are you trying this while the engine is running? Don't do that.

James
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Marek
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Re: MS3X and batch fire

Post by Marek »

Dear James,

Is that "don't'" advice also good for the "Injector Sequential Modes Testing"? from the "CAN-bus test modes" menu.

What are you suggesting will happen if a user does this on a running engine?

kind regards
Marek
Matt Cramer
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Re: MS3X and batch fire

Post by Matt Cramer »

It will stall. :D
Matt Cramer -1966 Dodge Dart slant six running on MS3X
suberimakuri
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Re: MS3X and batch fire

Post by suberimakuri »

Batch fire = 2 sq alternating
Semi = 2 sq simultaneous
Seq = 1 sq simultaneous.

Personally not a big fan of semi with big injectors, they are often not very reliable at very low pulsewidths. Running semi means two pulses per cycle so PW halved into the low pulsewidth territory. Had been chasing a very low load miss/erratic AFR until went back to batch fire. MS3X with sequential ideal.
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