Ability to scale up the engine

I have a Tomberlin crossfire 150 with the GY6 and will go to 171cc shortly and will go to 232 as soon as all the parts become available again. Will the system have the ability to work on all 3 cc sizes?

I’d be interested in getting a definitive answer to this question as well as someone who has gone through the process of scaling up from a 150cc GY6 to a 171cc and now a 232cc.

There is a particular manufacturer of an EFI kit that informed me I would need to upgrade to a 34mm throttle body at an exorbitant cost in order to run their setup on my 232cc, despite the fact that the engine has a 28mm intake manifold.

Hi! I can give you my thoughts, but I am sure Travis will chime in when he can. First, there is no definitive answer, as all variables are in your hands. Things like air box size and configuration, or worse, no air box are big things to ponder and tune for.
Ignition timing, cam timing, compression ratio…pipe lengths.
Hopefully you see that they all have an effect on your question.
That said…The Nano will surely be able to handle those as you “scale up”, but the EFI controller cannot automatically detect your VE, for example. (Volumetric efficiency) The number you put in as a base, (Engine cc is one of many, many parameters) will determine the injector targets, based on a stoichiometric sweet spot. (Air:fuel ratio) In a perfect combustion, that is 14.7…the sweet spot is what your engine can do.
So, as you build in capacity, that will change and so will your EFI targets. The easy answer would be, YES, it can do it. The real answer is never that easy. The upgrade you seek in cc might require a bigger throttle…might not. It may also require a larger injector, depending on your injectors capacity. You would likely have to up size your exhaust or even change head flow…that might be your ultimate restriction at 232cc. Whichever manufacturer gave you an estimated throttle body size, likely did so based on industry norms. My 250cc CRF/CBR engine worked better with a 38mm. (36mm was stock)
I don’t think there is an EFI controller that will do what you ask. There are VE table calculators on the web, that you can plug in your engine data and see the differences, so you can plan. It is more involved than you might think. A second option is to find one that has done that, as you are asking…steal shamelessly!

Thanks. By saying “definitive,” I certainly did not mean “please guarantee that I will have a completely painless installation process after purchasing a NanoEFI kit.” I don’t expect NanoEFI to be completely “plug-and-play,” but it’s nice to have an idea of what is possible and what is not. By no means would I view any of the stumbling blocks along the way as Travis’ responsibility.

I’ve seen people running the bootleg Aliexpress kits with 28mm throttle bodies on Taida 232cc GY6 engines (which isn’t to say those people are better off from a performance standpoint with that type of setup compared to a larger carburetor - IMO they’re not), but to be told by said manufacturer that forking up an additional grand for a kit with a 34mm throttle body was the only path forward had me a bit miffed. I’ll gladly save my money and wait for the NanoEFI instead.

I do however appreciate your detailed response and walking through some of the considerations.

Hi again Sub…I think you are on the right track. The throttle body size is one issue, but not THE issue. Depending on your own abilities…the answer is quite a bit cheaper than a “Buy all my shite” deal…as you would assume. I make my own cheap and easy…TIG welded.
My keys to look and see are simpler. (for a 4 stroke) start with the ID of the big bore kit inlet port for your engine. That is the diameter of your TB to head pipes starting point and will be close…but is needs to be fairly SHORT. The throttles are a tad more confusing. Cheap ones have a throttle plate with a bore that is the same on both sides. (NG in my book) Better yet…for high flow, the body should be slightly smaller in the inlet and the same (bigger) as the port at the outlet…makes life easier. Higher velocity and better mixture.
So the answer can be simple in your scenario, but IMO…not likely. Learn to fab your own parts…like Burt Munro and fly!

I’m a little late, but welcome @EEkedOut :wave:

I own a Crossfire 150R, great machines!

The short answer is yes. The NanoEFI ECU is capable of handling 150cc, 171cc, and 232cc sizes.

As @thaigyro pointed out, there other considerations outside of the ECU that go into tuning for major combustion chamber changes. But in a nutshell from a hardware and extra cost perspective, you’d be looking at changing your throttle body and injector out for large sizes respectively. So around $125 or so would be my estimate.

When it comes to tuning, fortunately the GY6 is so common (and I come from the GY6 scene myself) that we’re sure to have good base tunes quickly for most or all of the common GY6 bore/stroke combinations and cam profiles. My personal favorite is the 184cc stroker with machined piston (rather than shims). 150cc and 184cc will likely be the first “official” GY6 tunes available.

And with WiFi internet connectivity built into the ECU, tune sharing within the community will go a long way to help support a variety of engine build profiles that I might not otherwise be able to get around to doing myself.

:face_with_raised_eyebrow:…or four full NanoEFI kits at that price (including 4x throttle bodies).

Yeah, that kind of thing isn’t going to happen here. I can currently get higher quality 28mm and 34mm throttle bodies than what comes in the Aliexpress kit, at reasonable cost. Would likely be priced around $100 if I were selling them right now.

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