Actual best way to dpmi

Twisted Tuning

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Does that mean we are at point where more advanced tuners aka you v8 ,motiv,etc can pull this off?

That was mainly for the comments about shift farting or whatever people wish call it.


But, its ironically the same fo what you are trying to propose about DP meth. it's all about the injection timing of you want to get into sequencing meth injection.

Realistically, it's not overly hard to do. Hell, I have a system on one of my other cars that runs secondary injectors sequentially base on primary injector signal. never tried adapting to N54.

Just would need a separate voltage feed for the secondaries since the 100+volts fr he Piezos would burn up the secondaries in short order. And justwire the ground trigger to the secondaries.

It's honestly fairly easy. Would just need to test injection timing and possibly adjust since DI and PI typically fire at different crank angles of the cycle.
 

Jake@MHD

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Any chance i could bribe you to use spark cut like some n55 or does dct n54 use spark cut i would think that would make easier?

N55 does not cut spark. You probably aren't going to find a production car today that does due to emissions reasons. They all cut fuel and/or retard spark (depending on the situation), usually a combination of the two.

The shift "noise" is from a tiny bit of fuel making it into the exhaust before it is fully cut. I'm not sure if the N54 DCT cars sound the same when shifting as the N55, never heard one in person. If not it could be done sure, but I have more important items on my plate right now :)

It's honestly fairly easy.

Not that easy. DI can be split across multiple injections per stroke, with a varying fuel quantity. The injection times are also extremely short compared to PI and like you said, a much different injection window. It's not worth the hassle.

Progressive meth controller with voltage output for flow + FlexFuel logic + "PI safety" coil disable on DI disable = very safe and robust system with no addition parts needed.
 
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Rob09msport

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N55 does not cut spark. You probably aren't going to find a production car today that does due to emissions reasons. They all cut fuel and/or retard spark (depending on the situation), usually a combination of the two.

The shift "noise" is from a tiny bit of fuel making it into the exhaust before it is fully cut. I'm not sure if the N54 DCT cars sound the same when shifting as the N55, never heard one in person. If not it could be done sure, but I have more important items on my plate right now :)



Not that easy. DI can be split across multiple injections per stroke, with a varying fuel quantity. The injection times are also extremely short compared to PI and like you said, a much different injection window. It's not worth the hassle.

Progressive meth controller with voltage output for flow + FlexFuel logic + "PI safety" coil disable on DI disable = very safe and robust system with no addition parts needed.
Do you have a recommended controller ?
Also with piggybacking off of the di you would tap then run a secondary mosfet as not to increase load on dme so literally would just be a trigger but your flex fuel negates need for that complexity. Also i may be wrong but i feel the timing is of no concern as it is pi and the volume is important not the timing thatd why nozzles are even possible.
 

V8bait

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Do you have a recommended controller ?
Also with piggybacking off of the di you would tap then run a secondary mosfet as not to increase load on dme so literally would just be a trigger but your flex fuel negates need for that complexity. Also i may be wrong but i feel the timing is of no concern as it is pi and the volume is important not the timing thatd why nozzles are even possible.

Volume and timing are important, as the di can fire into the combustion stroke when the intake valve is closed, but volume is more important. The DI injector will fire for a wide variety of time based on hpfp and calculated fuel mass, a much different and hugely variable timing scheme that makes a simple on/off pretty unusable. When I was looking into this we were kicking around the idea of a few inputs and a rolling window to calculate fuel and PI based on a percentage of that with the window watching for injector shutoff, however it got complex fast, and honestly with the current implementation of the output and spark disable safety, it's not a big deal anymore. Getting everybody to use the new systems and safeties rolled out should be the push, not a new controller imo.
 
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Rob09msport

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Volume and timing are important, as the di can fire into the combustion stroke when the intake valve is closed, but volume is more important. The DI injector will fire for a wide variety of time based on hpfp and calculated fuel mass, a much different and hugely variable timing scheme that makes a simple on/off pretty unusable. When I was looking into this we were kicking around the idea of a few inputs and a rolling window to calculate fuel and PI based on a percentage of that with the window watching for injector shutoff, however it got complex fast, and honestly with the current implementation of the output and spark disable safety, it's not a big deal anymore. Getting everybody to use the new systems and safeties rolled out should be the push, not a new controller imo.
So you don't really have preference for controller as long as using the flex fuel logic. I def will go hs4 then as pretty sure you and jake the most knowledgeable.
 
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Rob09msport

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It wasn't mentioned in any of the flex fuel posts because it will not be available in "OTS" fashion, but the flex fuel code also supports progressive meth / meth safety. If your meth controller has a 0-5V style output, you can format your bin for FF and just wire up the meth controller output to the same DME pin used for the FF ECA. Then as your meth starts flowing, it will seamlessly interpolate to your higher boost / timing tables, and can also safety fallback to the "no meth" tables if it stops flowing for whatever reason.
Was just making list of what to order for this and i was thinking about it. My question is what is the response time for how quick it would interpolate and alter map based on flow. I like the idea of being able to use a flow sensor and never have to worry about the dme getting ahead of the meth as far as timing and boost. I would think that it would be more of straight switch of maps though and not much in between since it's not like e85 with different mixtures, this would just be a way to fail safe where you would still have your 93 tune if you turned off meth. I guess the question is would you use flow sensor or instead have your controller drop you to your 93 map instead of dumping boost etc?
 

Tuppidsay

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So the "altered code" that disables spark. Is this only part of ff module? Or is it included during any flash, like during a BEF?
 

Jake@MHD

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Was just making list of what to order for this and i was thinking about it. My question is what is the response time for how quick it would interpolate and alter map based on flow. I like the idea of being able to use a flow sensor and never have to worry about the dme getting ahead of the meth as far as timing and boost. I would think that it would be more of straight switch of maps though and not much in between since it's not like e85 with different mixtures, this would just be a way to fail safe where you would still have your 93 tune if you turned off meth. I guess the question is would you use flow sensor or instead have your controller drop you to your 93 map instead of dumping boost etc?

Interpolation update is every 10ms, so basically instantly.

So the "altered code" that disables spark. Is this only part of ff module? Or is it included during any flash, like during a BEF?

It is not released yet (another 2 weeks most likely), but will be a checkbox for any flash.