2-stroke 3 cyl snowmobile.

[bjorkmanders]

Have put a MS3 in a 3 cyl turbo 2-stroke (have also asked this in freeems forums) would like to know whats possible to do with RusEFI and Frankenstein.

Specs:
2-stroke(360 degrees working cycle)
6 injectors.
Cdi with cop.
Pid wastegate
MAF (frequensy based)
2 fuel pumps(preferably controled with 2 gpio pid controllers via solid state relays)
Relay to turbo oilpump
Hall-sensor
36-2 teeth wheel on Crank.
Launch control.
Rev-limit control.

I realise this is to much. But to know whats possible to do I can plan accordingly

Regards
Anders

[AndreyB]

We have not yet got our hands on a vehicle with a turbo so no wastegate or launch control yet - but once there is someone ready to try/test/provide feedback, I have the time to implement whatever would be needed.

If the Frankenstein would not be enough in terms of I/O channels we can add an extra 6 channel expansion board. There are plans to add a couple more channels in Frankenso but that's still pending.

360 cycle is provisioned for. Extra gpio with for the extra devices should not be a problem. I guess what I am trying to say is
a) no, we do not have some of that stuff ready
b) yes, let's makes this happen if you want to get involved

[bjorkmanders]

Right now working with another snowmobile project. But sounds really interesting


what would be required from me in this project?

Describe features/functions.

Buing hardware, would like to buy as much turn key as possible.

Connect hardware to snowmobile.

Test software and report problems/bugs.

Is there something else forgotten ?


Would be really good get this platform 2-stroke friendly , have a bunch of projects in my head ( and hopefully good hardware for other 2-stroke builders ) ......


It's free software ( as in freedom ) ? And will it always be free
( not like others who closing it more and more ) ?

Regards
Anders

[AndreyB]

what would be required from me in this project?

Time mostly.

Buing hardware, would like to buy as much turn key as possible.
Connect hardware to snowmobile.
Test software and report problems/bugs.

Yes see http://rusefi.com/wiki/index.php?title=Manual:Current_Status

Would be really good get this platform 2-stroke friendly , have a bunch of projects in my head ( and hopefully good hardware for other 2-stroke builders ) ......

Time, do you have the time? Too many people with ideas. Too few people with... time

You've probably seen the stuff for sale if you do not want to solder it, but that's definitely not a turn key product. We have not yet started a two-stroke engine, but we are definitely interested if there would be a person to install this with our help if needed.

It's free software ( as in freedom ) ? And will it always be free
( not like others who closing it more and more ) ?

This is free open source software as in http://www.gnu.org/copyleft/gpl.html. Once something is published under GPL I believe it's impossible to revoke it.

[kb1gtt]

About hardware, it looks like you have enough outputs for 6 injectors and 3 spark channels, as well you should have all the inputs like hall, TPS, IAT and such sensors. Here are my concerns from a hardware stand point.

The spark drivers can probably drive your CDI, but I would need more information to make sure. Do you have a reference schematic for the CDI? The spark driver is a hi/lo driver, originally posted by a member of the FredEMS forums. It can drive to either +5 or +12V and it drives to 0V for the low drive. This works with a large array of ignition circuits.

My primary concern is the frequency based MAF. We don't have an existing circuit for that. The circuit may be as simple as an RC low pass filter, or it might be far more complicated. This is an unknown for me from a hardware stand point.

About PWM control for waste gate and 2X fuel pump. The on-board MOSFET's were designed for high impedance injectors, so designed for 1A. These may draw more current and may require a different MOSFET. It might be best for an external MOSFET. I wonder if this might be a software issue. @russian, is it a feasible option for 3 to 4 channels of PWM output with a period of say around say 1kHz? Is that an addition to the timing events, or is PWM vs RPM based a potential issue? I really need to spend some time getting friendly with the software side of it.

What is the expected max RPM? What kind of power can the alternator supply?

Might be worth noting, Frankenso includes an option for an LCD, which makes it possible to tune with out a laptop or PC. This could be a handy feature on the trail. Also please note that the software for this option is not yet developed. russian is making very good progress with the software support, but many possible features are yet to be developed.

[bjorkmanders]

Russian:
Oh I have not planed doing all those projects in near future


About cdi. It's either a msd dis-4.
Or a own built using the stator ac voltage to charge caps to 400-500volt. Release the current in the caps with a 5 volt signal sent to a thyristor.

The MAF outputs a pulse signal, with the frequensy corresponds to a massflow. The software calculates the frequensy. And then use a lookup-table to get the maf ( at least thats how it was done in ms3 ).

Thought of using solidstate relays driving the fuel pumps. Used walbros 255lph (arround 10amp a piece) pumps with a aeromotive pressure regulator. This setups draw to much current for my alternator. Thats why pwm pid is needed. 2 fuelpumps is for using 2 different fuels. Same with 2 injectors per cylinder.
Higher octane when turbo pressure rising.

Max rpm for this engine is arround 8000 rpm. Other engines could go a bit over 10000 rpm. Alternator is arround 300-400 watts.

Will tune the engine mostly in a dynomite-dyno. It's however a realy nice feature with the LCD tuning

[kb1gtt]

So MAF is 0-5V square wave? That should be doable with software. Sorry russian, I always claim it's just software

0-5V for ignition should also be fine.

LCD is handy for when you're on top of a mountain and you find 02 concentrations have changed from when you were at the dyno elevation. AKA, %O2 in the air varies for a variety of reasons. So 1 cubic meter of air at 1 bar and 20C, will contain more O2 at sea level than at the top of a mountain. This variation in O2 will change flame front speeds, and such. If you don't have rich/lean feed back (O2 sensor) you may need to make an adjustment just to get home. % humidity will also change the flame front significantly. Lots of things can be a bugger in the real work relative to the dyno, then the LCD can be handy. As well your PC will probably get a virus the day before track day, and you'll be screwed.

Any how, it seems the hardware is already there. Let russian know if you plan to give it a try, and he'll likely put in some effort into developing the features. For now I believe he's focusing on items that are at arms length.

[bjorkmanders]

Yes square wave, from 0-14khz ( see http://ls1tech.com/forums/pcm-diagnostics-tuning/1715514-ls3-ls7-maf-sensor-dropping-signal-wot.html for a plotted transfer function ) . The signal is pulled to ground, so a pullup with whatever voltage you need.
Freq MAF is the shit, no ADC and other disturbance. Just a square wave and processor power

The beauty with MAF is that you get the mass air flow, no need compensate for temp/altitude ( at least in theory (: ) But I totally agree ( I'm not a smartass, seriosly ) about the LCD will come in handy in the woods or at the track. However virus is not likely, stopped using winblow years ago ( again, not a smartass. I promise S: just take my chance when mocking Microsoft is an option ).

Working on the decide part ( time and money mostly ) . I really like the energy and stuff in this community. Never worked in a truly open source environment before. Will talk to Russian when ready

/Anders