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Small Engine Efi Hydrogen FAQ

Small engine EFI is not new any more.

 

More and more small engine manufactures switch from carburetors to EFI either because of the more stringent emission regulations or the market demand for better products. EFI has a lot of advantages over the carburetors, as it has been proved by auto industries.

 

One major hurdle for small engine EFI applications has been the cost. The add-on cost of the EFI system has been prohibiting to the OEMs to replace the carburetor. This problem can be mitigated by mass-production of the

EFI components.

 

We believe that these kits can pave the way to a hydrogen economy.

 

However, there are a lot of small engine applications that do not meet this prerequisite of large volume production. Those applications can be very specific to certain niche markets, like racing bikes, go-carts, ATVs, tractors, mowers, even model air planes. Further, these small engine applications are quite different from one to another, as you can see.

 

Market has been demanding a low-cost, flexible EFI kits for those small engine applications. And we are responding to it. We are the manufacturer of small engine EFI systems.

 

Our products include the small engine ECUs, small engine EFI conversion kits, Accurate Lambda Meters (ALM), and even a small engine simulator.

 

The unique advantage of our products is flexibility. We develop the customized small engine EFI system for small volume customers in a very short time and with very low development cost. How do we do it? by using the state-of-art technologies like: scalable semiconductors, and model-based-designs, etc. You don’t have to know what they are, and you just need to know: when the technology and manufacture meet, they suppose to speed up the development and reduce the cost.

 

That’s exactly what we do.

Our current product lines include:

2-stroke small engine EFI kits,

4-stroke small engine EFI kits; supporting 1-cylinder or 2-cylinder engines, whether they are in-line 2 or V-2, or symmetric 2-cylinder engines.

 

Our 2-storke EFI kits support 1 or 2 injectors per cylinder, and the 2 injectors can be one small and one big, to cover the low idle RPM all the way up to 16000RPM.

 

Our 4-stroke EFI kits can be full Plug-And-Play (PNP) kits by using the O2 sensors, as our ECU has a very sophisticate algorithm of self-tuning based on the close-loop controls. Got a wideband controller? That’s even easier to do self-tuning with our ECU.

 

You’ve got 2-cylinder engines which require a 2 bank control system (each cylinder has its own O2 sensor). No problem.

 

We have it in stock.

 

Our EFI kits can run the engines with displacements from 35cc all the way up to 1200cc. Because we have different sizes of injectors (38, 60, 80,128, 200 g/min flow rates, and more.) We have variant size of fuel pump too, (10 to 100L/H volume flow rates).

 

Mainly the missing part here is the throttle body. Right now, we don’t have all kinds of throttle bodies.

 

But the good news is a lot of customers can get their own throttle bodies off the shelf. Or they have the capability to manufacture their owns or adapt to the exiting throttles.

 

What is the only thing that really blocks the small engine EFI? There is probably none except people’s mindset.

 

 

 

Frequently Asked Questions


How easy is the EFI conversion?


The conversion is fairly easy, if you don't mind some hands-on work.

Often our customers take this as fun to convert a carburetor engine to an EFI engine.
The success of the conversion itself and the achievement of better performance, or fuel economy, or the help to the enviroment, depending on your choice of tuning, are often satisfying to justify the efforts.

Since our kits, for some popular small engines, like GY6 125cc engine, can be close to PNP kits, the most part of efforts is actually the installation. Once the installation is done, and done correctly (more important), the kit will run and tune by itself in many situations.

The most challenging part for some customers are to connect the wires correctly. There are 2 important wires need to be connected to the stock electrical system correctly. One is the ignition pickup up wire and the other is the key-switch wire. A digital multi-meter (DMM) can be used to figure out these 2 wires on your bike.

Compared to the electrical wiring work, the mechanical work is kind of straight forward. Some extra installation work or parts may be needed depending on your engine. Our kits are mostly complete for scooters, monkey bikes. Contact us if you think your engine is very different and needs extra parts.

 


Is this EFI kit easy to tune?


Yes, it is.

There are 3 levels of the tuning:

Level 1: self-tuning. You don't really need to tune. You just need to install the whole kit correctly, including the wiring and the O2 sensor. The EFI kit will tune itself to your engine.

Level 2: easy tuning. All you need to do is to tune the air/fuel ratio (lambda), by change the desired lambda table. In ProCAL menu, go to "Calibraion" -> "Coordinations" -> "Desired Lambda"; it will show you a 16x12 table of lambda, dependent on RPM and TPS. By changing the desired lambda, you are commanding the fuel other than the stoicometric fuel. Usually many people tune the lambda to 0.85, for example, at WOT for better perfomance.

Level 3: advanced tuning. There are hundreds of other tuning parameters (calibrations) available via ProCAL. Besides the basic calibrations under the menu "Calibraions", you can find others more than you can imagine under the menu of "Advanced calibrations". To really understand those calibrations, contact us for the "strategy book", which is a WYSIWYG (what you see is what you get) graphical flow chart.

 


Can this kit be PNP?


Different people have different understanding of PNP. With our EFI kits, for certain types of small engines, it can be PNP. It means you can install the kit to your engine, and fire it up and run it immediately. Again, for certain types of engines, tuning is not required. The ECU will tune itself and adapt to the engine. All you need to do is to fill in the engine displacement and fuel injector size (we can pre-load them if you tell us when you order the kit). Contact us for whether your engine can be converted as PNP.
With this being said, you still need to PLUG IT! which means to install the kit correctly and completely (including the O2 sensor)
It turns out most issues of our customers are to correctly install the wire harness especially the 4 loose-end wires. Even with detailed instructions in the manual, it can still go wrong because of so many different engines out there. So we strongly suggest you to read carefully through the manual before you start to install the kit. You can always contact us if you are not sure about something.


What is the self-tuning and how does it work?


Self-tuning means our ECU can tune the engine mapping by itself.
How? First let's see how a human tunes the engine: he would use a lambda sensor (O2 sensor) to measure the lambda (AFR), and manually tweak the fuel map little by little until it's close to stoicometric AFR (14.7 for gasoline)
While, our ECU is doing the exactly the same thing by itself: it looks at the lambda deviations from the stoic AFR (based on the O2 sensor), and keeps adjusting the fuel, to maintain the AFR closely around the stoic. This is what people call close-loop control. Our ECU does more: it not only does the close-loop control, but also memorizes the deviations of the lambda at different load-speed operating points, and stores them in the non-volatile memory (so they are not lost when you turn off the ECU power). After the engine runs for a while, eventually all operating points will be learnt and memorized. The ECU will use the learnt data to pro-actively control the fuel to get a stable and precise AFR control.


How does the performance switch work?


"Performance Switch" has 2 positions: ECO vs RICH.
In ECO position, the EFI will run the base fuel "map", or stoicometric AFR (normal cases), which gives the best fuel economy, and least emissions.
In RICH mode, the EFI will run the enriched "map", or rich AFR (at high load, high RPM, esp. at WOT), which gives more power.
"Performance Switch" is meant to let the user's easily switch between the economy and enrichment modes in real-time, so that he can run for economy when cruising around the town; and can immediately switch to performance mode as he wants.

OFF -> ECO -> STOIC
ON -> RICH -> POWER

 


How to use ProCAL to log data?


1) Run ProCAL (load the correct A2L and CAL file).
2) go to menu -> run -> connect
3) go to menu -> run -> dispaly -> select "number" instead of "gauge"
4) go to menu -> run -> start measuring (the numbers in the display window should change now...)
5) go to menu -> run -> start recording
6) when you done the test, go to menu -> run -> stop recording
7) go to menu -> run -> data analyzer
8) In Data Analyzer, click "load", it will pop up a window, show the folder: "...\record"; that's where the logged files are.
9) Note, every time, the ProCAL can log multiple files, with the same name except the different suffix: _20ms, _100ms and/or _syn; These files are logged at the same time, but at different sampling rates. You will need to copy all those log files, and send them to us.(don't change file names)


Does this kit support 2-stroke engines?


Yes, we have released the 2-stroke engine kits soon.


Does this kit support Turbo charged engines?


Yes. You need select 2.5bar MAP sensor and a bigger size injector compared to the naturally aspired (NA) engine. Rule of thumb: the flow rate of the injector should be 1.5 to 2 times of the NA version.


What is the smallest engine does this kit support?


50cc. Theoretically, the kit can run smaller engines. But you will run a little richer at idle because of the smallest injector size of 38g/min.


What is the biggest engine does this kit support?


No limit. Practically, the biggest single or twin cylinder engines we can find are 1200cc.


Does this kit support 2-cylinder engines?


Yes. We have Ninja 250 twin-throttle available. For other 2-cylinder engines, a customer twin-throttle is needed.

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