Installed a HFS-2 system on my 335i with N54. I have some questions.

[cstavaru]

Hi,

Today I finally installed the Aquamist HFS-2 Kit I have bought from you a few months ago in my BMW 335i with N54 engine. I would say it's working great and I want to thank you, I was astounded on how much thought has been put in providing a package with everything needed for a smooth install.

I have some questions, if you don't mind:

1. I was provided with 3 nozzles, 2x0.7mm and 1x1mm. I installed the 2x0.7mm nozzles BUT it seems they are built differently and one is spraying a lot more than the other. The one spraying more has like 2 nuts on top of each other and seems a bit longer. Both have red rings around them. Do you have any idea of this problem ?

2. I am using the kit with a GIAC flash which has one Race map (16.5psi - factory is 8psi) which needs race gas or pump gas and methanol for a minimum of 104RON octane (about 100AKI). I am trying to spray enough methanol to satisfy the octane need but I can't seem to manage to stop the timing drop from the ECU. I am using 50-50 meth/water mixture with the two 0.7 nozzles and the gain potentiometer set at 50% (threshold set at lowes setting), but it does not seem to spray enough. What should I do ? Should I replace the lazier 0.7mm nozzle with the 1mm nozzle ? Should I increase the meth concentration ?

3. The system seems to not trigger at all unless the threshold potentiometer is set close to the minimum position. Is this ok ?

4. Do you have any idea how many CCs of flow do the N54 injectors have ? This way I could better calculate jetting.

Thanks,
Catalin

[Richard L]

Answers to your questions in Blue

Hi,

Today I finally installed the Aquamist HFS-2 Kit I have bought from you a few months ago in my BMW 335i with N54 engine. I would say it's working great and I want to thank you, I was astounded on how much thought has been put in providing a package with everything needed for a smooth install.

I have some questions, if you don't mind:

1. I was provided with 3 nozzles, 2x0.7mm and 1x1mm. I installed the 2x0.7mm nozzles BUT it seems they are built differently and one is spraying a lot more than the other. The one spraying more has like 2 nuts on top of each other and seems a bit longer. Both have red rings around them. Do you have any idea of this problem ?

The standard kit comes with 0.8, 0.9 and 1mm. If you requrest non-standard jet with the kit, they wree probably not from the same batch. We alter our jet design quite frequently. It is not a problem.

2. I am using the kit with a GIAC flash which has one Race map (16.5psi - factory is 8psi) which needs race gas or pump gas and methanol for a minimum of 104RON octane (about 100AKI). I am trying to spray enough methanol to satisfy the octane need but I can't seem to manage to stop the timing drop from the ECU. I am using 50-50 meth/water mixture with the two 0.7 nozzles and the gain potentiometer set at 50% (threshold set at lowes setting), but it does not seem to spray enough. What should I do ? Should I replace the lazier 0.7mm nozzle with the 1mm nozzle ? Should I increase the meth concentration ?

If you are running 2x 0.7mm jet, you will be getting around 550-600cc/min after taken in to account of system losses. (15-20%). I suggest putting the 1mm jet inplace of a 0.7mm jet. You can reduce the flow by dialing down the "gain" trimmer. In this type of progressive system - matching the exact jet size is not as important, as long as you over sized them.

It is better to start at 100% methanol and work you way downwards towards 50:50. I suggest this because the ambient temperature is not too high (Romania) at this time of the the year, water is not as effective compared to methanol below 20C. If you take this route, must put the 1mm jet in place of the 0.7mm.


3. The system seems to not trigger at all unless the threshold potentiometer is set close to the minimum position. Is this ok ?

This the nature of a direct injection system, the idc is not stricly linear to fuel flow because the total flow is a factor of the line pressure (HPFP). I would strongly recommend tapping the blue wire of the grey connector to the high pressure fuel line sensor. I am not sure which pin number of the ECU.

I have been trying to get those info for months without success. The only way this can be done is to trace the wire from the sensor itself (at the end of the fuel rail). Alternatively, you can use the MAP sensor (I think pin10 of the 44 -pin ECU connector plug).

4. Do you have any idea how many CCs of flow do the N54 injectors have ? This way I could better calculate jetting.

I do not know this but I can estimate the fuel requirement in the region of 500cc per 100hp.


Thanks,
Catalin