Supercharging BMW E90 N46B20 320i 4cyl

[SlavPala4a]

http://www.e90post.com/forums/showthread.php?t=384027&highlight=supercharging
This is a link to my thread. Please spend several minutes to catch up on my idea because I could really benefit from the brains inside this forum...
The great issue know is on theory how I could manage to fool the original MAP sensor not going in limp mode after sensing boost.
I have just bought MF2 powerful driver and I would also need all kind of advice for additional injector/s setup.
I tried to search something for driving fuel injectors by MF2 but I didn't find even one thread.....strange...
PLEASE LET'S DO SOME TALKING! :rolleyes::rolleyes:

[Richard L]

I read your link.

I saw your four- injector assembly (very nice bu BTW, wouldn't it be easier to have them at each runner for better fuel distribution?

[SlavPala4a]

I could buy a spare Intake Manifold and install the injector bosses right at the top of every intake pipe (if something is not well enough or the setup just do not work, I could easily just change the manifold and return back to the original NON moded one). This will make the setup sequential but could you be more detailing on the part: "at each runner". Do you mean I have a 4T engine so every injector sprays individually for every Tact? How could that be adopted via my gadgets and if you could give me a visual example I would be thrilled to see it!

[SlavPala4a]

I am new in the whole tunning field based on practice. I am reading a lot past several years but the theory is "fake" without an actual implementing in the practice.
So just generally speaking, do you think that I could do the job leaving the Engine management to the original ECU until I boost up and from this point upwards tune the proper AFR via MF2 and WaterInj?
Again, let's say my original map is 1Bar...if it is left in the OEM place, will it sens pressure above 1BAR? Will it inform the ECU that something is abnormal?
How should I trick the OEM Map to sens values like original until boost and after that just to feed the ECU with the maximum voltage related to 14.7psi absolute pressure(or theoretically speaking the biggest value that a NA engine with 100% VE could ever reach)?
Many questions...but that is the idea to share :rolleyes:

[Richard L]

I think the MF2 can take over from 1 atoms upwards.

There are several ways to stop the OE ECU seeing the boost pressure.
1. By ECU reflash (you need a tool)
2. By putting a MAP sensor clamp. ie, it limits the MAP sensor signal from going above a preset voltage.

I think the second method is easier to do.

I have also notice that you are going to use a PPS system (progressive pump speed) for methanol injection.... few comments below:
1. The PPS system do not have enough dynamic range to cover a supercharged engine. a 50-250psi (pressure change) only give a flow range of 1: x2.3
2. Supercharge has very fast load change compared to a turbocharger. the PPS system is too slow to react to an instant throttle change dus to the rotating mass of the pump motor
3. The meth flow is not linear to pressure change
4. PPS system without an inline valve will dribble after switching off due to the pump running on.

[SlavPala4a]

The idea of my project is not to mess too much with the OEM equipment - if possible NOT at all.
Could you be again more specific on the MAP clamp...should I just search it in Google or? It is probably made with a bunch of resistors, isn't it?

[SlavPala4a]

Here is a picture of the manifold that is used with my engine:

[Richard L]

A good voltage clamp is more involved than a few resistor. Example below:

1 Zener diode based map clamp:
It a low cost solution, a 4.7V zener will clamp any voltage above 4,7V but it is a very soft clamp, ie, it will start clamping from 4... 4.2 .... 4.5V etc. This will effect affect the MAP sensor voltage and your fueling will not be as accurately above 4V.

2. Active voltage clamp:
Using integrated circuit or chip to allow a very sharp and accurate point, normally use ajustable betweem 4.3-5V. Aquamist makes those devices for many companies but not advertised as our normal range.

[SlavPala4a]

Do you think that I should buy a 2Bar Map, from Sierra RS Cos for instance, or I should keep the fuel map 2D for simplicity. In the manual is written that If I am using a supercharger the graphic has steady increasing slope, without any major peaks or drops, so the 2D map will do the trick well enough?
I do NOT have a Throttle Body(TB) that really works as it is supposed. In the Tech Info by BMW is written that my TB will act only if the valvetronic system fails. In a normal condition it will be half opened at idle and fully opened onwards.
I will try to film this statement when I go back home for the holidays.

[Richard L]

I saw the picture of your enigne, where is the Supercharge going to be installed? Are yo going to modified the manifold and runners?

Most of customers (tuning shop and turbno kit manufactures) uses an independent MAP sensor on the MF2 and purt a voltage clamp on the OE MAP sensor.

It will work on RPM only (boost triggered) but it is worth using the full 3D capability of the MF2. A two bar-map sensor is not too expensive, but the result of a 3D fueling system is more refined. Judging the amount of work you need to do get the supercharger to work, it is not worth cutting cost in this.

[SlavPala4a]

I will try installing the SC around the OEM Air Filter Box(the one will be removed). There is a possibility the SC to be installed on the other side (left side if you are staying in front of the car).Finally there is also a lot of free space in front of the engine. The space is very tight but the SC is also very compact. I am sure I will find a way to squeeze it somewhere. My goal will be:
As close as possible to the engine(here 1cm is the best 10cm is the worst scenario); As little curves from SC->Aftercooler->intake as possible; a nice design for gripping the pulleys as much as possible.
As I said I really do not have a way to add a Throttle position sensor so will that be a problem with the 3D map - or let's say will it transform to a 2.5D :oops:
So for now it will be nice to buy a 5V Weber/Marelli style additional MAP which I could find in plenty OEM applications of the good 90s and a CLAMP for the OEM.

Absolute stunning discussion... you a helping me big time.

[Richard L]

Th eMF2 does not need a TPS, just boost and RPM.

[SlavPala4a]

Here is a sample picture of an E90 with the same engine as mine:
Either left or right side will be fine. The SC could be mounted horizontally, vertically or in any desired angle as far as the pulley aligns with the crank.
I will start with the mounting brackets, because if I cannot secure the SC in a way that NO belt slippage or damage occurs there will be no sense to continue on.
I have the chance to use the services of a professional water or laser cutter for pretty cheap price. This will assure perfect dimensioning and precise cutting.

[SlavPala4a]

Now I am looking for a solution to the sequential additional injection, but it will be very difficult for realization, as far as I could visualize it in my head.
First the manifold is plastic and welding would be impossible, so I have to design something unusual using the strapping points for the manifold plastic cover(In the picture above this cover is removed, as well as I did it a while ago). If I manage to solve this problem I will be facing the space shortage between the manifold top and the engine bay lid (bonnet/hood). However a 45 degree boss install would save some valuable hight and finally it could be realized but there are a large amount of unknowns in this equation. :? :?
I will research the google images from cover to cover on this topic and hope soon to post some ideas for discussion.

I am happy to say that I really hit the JACKPOT by registering in this forum. Thank YOU!
P.S. a photo from realoem.com for reference to the manifold

[Richard L]

Here is a sample picture of an E90 with the same engine as mine:
Either left or right side will be fine. The SC could be mounted horizontally, vertically or in any desired angle as far as the pulley aligns with the crank.
I will start with the mounting brackets, because if I cannot secure the SC in a way that NO belt slippage or damage occurs there will be no sense to continue on.
I have the chance to use the services of a professional water or laser cutter for pretty cheap price. This will assure perfect dimensioning and precise cutting.

Well, if you have access to a sheet meter cutter, the choice is limitless. I suggest putting the the side without exhaust pipes

[Richard L]

as secondary injector only comes on under boost, the mass air airflow in the runners is also supersonic, you can place the injector anywhere along the runner. I belive the plastic used for the manifold is made of hard plactic, drill and tap and could be a solution.

Dod the E90 engine at some point used a cast metal manifold? Worth looking through history.

[SlavPala4a]

Ok so I am planning on using one Warer Methanol(actually Ethanol but I am still reading on this topic) nozzle and what could you suggest me for the FUEL Injection? Should I have FUEL injector in every runner or something different? If you could refer me to a link or just anything...
The best position for the Water Injection nozzle is between SC an Throttle Body, isn't it?
I am waiting for a EFI book which will give me some more knowledge on how to crunch the numbers for the injectors.
I will keep you updated.
P.S. I have just bought a MAP + pigtail for making MF2 driver to produce a 3D fuel map.
***The MAP photo is a sample photo found in google, because I am still waiting to be shipped but it is the same genuine GM 3bar Map sensor + weather connector
*****Interesting write up on the GM MAP topic which somebody could find useful:
http://www.robietherobot.com/storm/mapsensor.htm

[SlavPala4a]

Better Photos of the Intake Manifold from different angles:

[Howerton Engineering]

Sorry I am jumping in here late and only skimmed the thread. You mentioned you do not have a typical TB, that it is half open at idle. How do you plan to throttle the SC? If you pick a ratio to produce boost at WOT, then that is the permanent drive ratio. Unless you have a way to "choke" the SC, it will try to make boost all the time.

Maybe I missed something and am off-base, maybe this has been sorted already?

[SlavPala4a]

There is a TB which in my case is called Valvetronic. Valvetronic is controlled generally by the DME(ECU) via several sensors. I will post later the technical information about the DISA and Valvetronic systems in my engine.
I was telling that the usual TB which is fastened to the Intake Manifold inlet works as a normal TB only when there is an error in the valvetronic control.
I am also selecting some of the most important information about the Mercedes's system which I am going to post later today.
See you

[SlavPala4a]

Here are some of the major sensors which feed the ECU with information in order to calculate the proper engine operation. Those are screen shots form the official BMW TIS database.

[SlavPala4a]

the second part of the info.

[SlavPala4a]

Some NEW detailed information for the N46B20 new features. If somebody is interested could take a better look at the images.
P.S. Sorry that the screen shots are not very nice but this is the best possible quality.

[SlavPala4a]

Continuing...

[Richard L]

good infos