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Originally Posted by Dackelone
I don't buy that. Ethanol allows water to attach to it. Hence it can get further down the fuel system and cause damage/corrosion. When the E10 and E05 fuels started to come out in Germany(2011)... even BMW(and other car makers) were telling us different things. Some said within the company its ok, but the engineers said it was not good over the long term.
Sulfur free gas and the new E10 fuel in Germany…
http://www.1addicts.com/forums/showthread.php?t=485903
Today most German gas stations sell the regular blend fuel, which is E10(10% ethanol) 95 octane, called: Super. Then they have another Super with is also 95 octane but only has 5%, called E05 Super. And then we have our premium fuel called SuperPlus 98 octane which as NO ethanol.
I only use 98 octane SuperPlus in my car.  |
Here's one of the posts I was alluding to. I'll try to find the others. All comments are on the N54 itself and fueling capacities. Interview with an unnamed VDO Continental engineer.
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Today i had my follow up conversation with the tech guy at continental. Here are the questions and answers. Enjoy !
Are the pistons forged pistons ?
- Don’t know
Does the N54B30 use homogenous or stratified charge under high load ?
- The engine was developed to run in homogenous mode. The N53 engine was to run in a stratified mode. Although the engine is capable of running in stratified mode, it currently does not.
It uses an outward opening injector.
Have you experience with this engine and E85 fuel or do you have any thought on it ? Can e.g. the injectors handle alcohol ?
We have a lot of experience with E85. Currently, we have an issue that if the injector is hotter than 100 Celsius, we are seeing melting of the fuel filter in the injectors. As long as the temperature of the injector stays under the 100 Celsius, this engine is perferctly capable to run E85. As a matter of fact, it will run E100 without any problem under cold conditions. There is no need to preheat the fuel.
We are investigating the filter issue, and we hope to have a solution next year. Whether or not we will create injectors for this engine, depends on the market (read: BMW).
It is not possible to replace this filter yourself; you cannot open the injector to get to that part.
Is the HPFP pressure of 90 bar constant or is it controlled by the MSD module ?
It is constant but indeed controlled by the module. The engine has been tested to up to 200 bar. If you keep the HPFP pump below that number, you could inject a lot more fuel. The relation between the amount of fuel sprayed and the pressure is not a linear relation but a Bernulli equation.
In our earlier conversion, you mentioned that under high load the TI is about 2 ms ? Correct ?
Yes maximum is 2 ms. Notice that the engine runs under homogenous mode and that means that the injection start in the intake phase. With this engine, it is no problem to keep injection into the compression phase, but not too long; it would be bad for emission. However, if the pressure of the HPFP is increased, this may not be needed.
The injectors have a maximum of 40 mg/ms spray at 200 bar. This is an increadible amount of fuel, much much more than any solenoid injector. It is this high, because when we designed the application, BMW insisted that the engine must be able - in limp mode - to only use the LPFP pressure, which is 5 bar, and still drive the vehicle at 170 km/h.
If correct, do you agree then that considering the ti in the compression phase, we can get it up to 4 ms for 7000 rpm ? Can we use the full compression phase ?
You would have to calculate it, but yes, there is extra time at mentioned before.
The injector can inject a lot of fuel into the cylinder. When increasing the injection time, and also when injecting in the compression phase, look out for cylinder wall wetting. This is dangerous. It would wash away the oil on the walls, causing wear. One way to check for wall wetting is to check the engine oil if it has fuel in it. Another way would be to check if the vapor of the exhaust gas recirculation (EGR) and see if there's fuel vapor.
The risk of wall wetting may be reduced by running higher boost, as it affects air flow inside the cylinder.
Running the HPFP at higher pressure may increase the risk again.
You said we should tune the TI duration of the ignition pulse. Can we also tune with the MSD via a reflesh when the ignition time starts ?
There is indeed a calculated ignitition start time in the MSD. It is not a map, but i'm not sure.
How does the ECU measure a knocking problem ? Does it use voltage ? Does it do it for all 6 cilinders individual ?
Each piezo injector has a knocking sensor. It measures vibration. By looking at certain frequencies, the knocking signal is sent.
EDIT: seems that the engine also has the standard knocking sensors in place.
De community is desperate to lean more about the MSD80. We would love to have information that can help us reflesh the unit to tune to engine for 600 PS. Can you help ? Can you direct us to a colleague (do you have a name ?) This is vital for my own project too !
I don't know about the MSD80. I'm an injection / fuel system engineer. I will talk to some colleagues and see if i can help you with anything. We have to make sure we're not infringing any copyrights and i think BMW owns the rights to the information on the MSD.
Can we buy this information ? Who should I talk to to ?
there may be a legal way to buy this information, i will talk to some colleagues and mail you back.
All of us want to invite you to join our forum N54tech.com. An engineer like you would be incredible value to the forum, may I mail you an invite to join ? It’s free of course !
Thank you for the invitation. I will think about it. I have to be careful not to share information that my company doesn't want us to share.
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