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mack85n

Best approach with 6 cylinder - 4 injector drives

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Which would be the best approach to wiring a 6 cylinder engine with individual injectors on an ECU (Link G4+ storm blue) that has 4 injector drives? 

Also what what is the idea behind batch injection being adjustable to have injection occur every 360 or 720 degrees of rotation. If tuning a traditional fuel map would injection durations be double for a 720 injection as opposed to 360 degree. 

Just looking for further explination on the tuning approach to this.

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I would set it to sequential and wire for a semi-sequential operation:

dNKyrYB.png

 

In real life there is usually very little noticeable difference in how an engine will run when comparing semi-sequential to multi-point group mode, but with semi-seq you may be able to achieve a slightly smoother idle and very light load operation.

In 360 mode your injector has to fire twice as often so pulse widths are halved and you have twice the dead time per cycle, this becomes an issue mostly only with very large injectors but I still suggest always use 720 mode if you have capable triggering. 

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I would set it to sequential and wire for a semi-sequential operation:

dNKyrYB.png

 

In real life there is usually very little noticeable difference in how an engine will run when comparing semi-sequential to multi-point group mode, but with semi-seq you may be able to achieve a slightly smoother idle and very light load operation.

In 360 mode your injector has to fire twice as often so pulse widths are halved and you have twice the dead time per cycle, this becomes an issue mostly only with very large injectors but I still suggest always use 720 mode if you have capable triggering. 

thanks,

 

i have base line specs for injection duration for the injectors I intend to run if set up as a fully sequential injection system. Would these inputs be the same for a fuel table on 720 degree injection in semi sequential ?

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If you have this setup, how is it best to approach setting injection timing? The typical method is to tune by AFR but 1/2 the cylinders will be different?

In my case, I may be looking at this on a flat 6 with two lambda sensors and ITBs, so can probably try and pick injection timing that matches (and I suspect it is slightly before valve opens on 1 / 3 / 5 which is 120 deg later on 2 /4 /6, although there is probably also an injection timing that would see both inlet valve "pairs" open if that was desirable).

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At idle and very light loads you can tune the injection timing using lambda, in this semi-seq case you would be aiming for lowest combined or averaged lambda. At higher loads it is generally tuned by torque output.  With semi-seq I suspect the difference between optimized timing and not optimized will be pretty subtle (~1-2%) so you may have trouble actually noticing anything.  Generally with mild overlap engines you will only see noticeable effects from injection timing below about 40% DC so I wouldnt both tuning beyond there.

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Thanks - appreciate the advice.

It's a high overlap 2 valve engine with ITBs so it might be sensitive. I guess I will find out...

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Sorry for digging up an old thread, but directly relevant to the above. If wired up as below, and there was a need to run the engine without the cam sync temporarily, would be the best alternative be multi point, 360*, and halve the master fuel (hoping deadtime are accurate)?

dNKyrYB.png

 

Edited by CamB

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I would set it to sequential and wire for a semi-sequential operation:

dNKyrYB.png

 

In real life there is usually very little noticeable difference in how an engine will run when comparing semi-sequential to multi-point group mode, but with semi-seq you may be able to achieve a slightly smoother idle and very light load operation.

In 360 mode your injector has to fire twice as often so pulse widths are halved and you have twice the dead time per cycle, this becomes an issue mostly only with very large injectors but I still suggest always use 720 mode if you have capable triggering

hey guys new to the forum i'am currently wiring in a G4 storm in to my ER34 rb25det neo the ecu had previously been wired for a rb25det s2 not knowing how they previous owners had wired the car im guessing its how you have mentioned in this thread as semi sequential injection i just want to be sure that a G4 storm is compatible to run semi-sequential injection and whats the best way to wire it up cheers

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Yes this would be the way to do it if you are starting from scratch.  If it is already wired for batch fire then you will probably find it will run perfectly fine like that to.  Semi seq you might be able to get slightly smoother idle and sometimes a little smoother run at light loads.

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