Interesting paper on ethanol DI

LamboLover

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Apr 6, 2017
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After reading it describes a past situation and doesn't present any novel experimental data, but some of its points back up other data that ethanol is best injected directly. Not sure how you handle a second tank for E85 and making sure the expensive HPFP doesn't run dry.
 
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dyezak

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After reading it describes a past situation and doesn't present any novel experimental data, but some of its points back up other data that ethanol is best injected directly. Not sure how you handle a second tank for E85 and making sure the expensive HPFP doesn't run dry.

Yes, this was a novel idea in 2005 but 2018...we are already on top of this and manufacturers are already doing this.
 

LamboLover

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It seems "our" biggest problem is a supplementary fuel system that is economical relative to the value of the engine whilst having good control, not the price or availability of ethanol (at least in the US).
 

Jake@MHD

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It seems "our" biggest problem is a supplementary fuel system that is economical relative to the value of the engine whilst having good control, not the price or availability of ethanol (at least in the US).

100%. If it could be made more generic to work to control PI sequentially on other engines as well, it may be worth the cost of development. If not, I don't see it being worthwhile solely for N54. The AIC has been fine on many 800whp+ cars. Now with ignition cut on misfires, etc as well, it's main safety concern has been addressed.

If the PI was being used at low load / cruise, then sequential injection would be much more important. At high load and RPM, even straight PI cars have to start the pulse widths well before a cylinder's valve opens to pool the fuel anyway.
 

LamboLover

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The main appeal to me of DME controlled PI is that it could use the same airflow estimate with shared fuel quantity calculated from it, and same tuning platform.
 

Jake@MHD

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The main appeal to me of DME controlled PI is that it could use the same airflow estimate with shared fuel quantity calculated from it, and same tuning platform.

Yea a shared fuel quantity would be pretty nice. You could kind of accomplish this in a hackish way if you setup the AIC map in a linear progressive way and then control the voltage going to it via a 5V output of the DME or your OBDII box.
 

Cornfed54

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100%. If it could be made more generic to work to control PI sequentially on other engines as well, it may be worth the cost of development. If not, I don't see it being worthwhile solely for N54. The AIC has been fine on many 800whp+ cars. Now with ignition cut on misfires, etc as well, it's main safety concern has been addressed.

If the PI was being used at low load / cruise, then sequential injection would be much more important. At high load and RPM, even straight PI cars have to start the pulse widths well before a cylinder's valve opens to pool the fuel anyway.
@jyamona, could you elaborate on the spark cut during misfire? Is this something you have been working on adding, or are we finding out that spark does get cut when the DME cuts off an injector?
 

Cornfed54

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This was a code change I had in mind for awhile, finally got time to do it and had @V8bait test and verify it for me.
That’s awesome news! Is this something you will be releasing to mhd in the near future as an add on? Id be happy to pay for some extra peace of mind, and for all the work you have done on the platform.