So, the grom destroys all in terms of people expending many times the original purchase price on modding. As such there's a ton more people researching all options etc.
I started looking at the grom as they have the same 33pin keihin ecu as our cbr300r. Ive downloaded the service manuals for both, and most of the wires go to the same pins. All the ones that fuel controllers intercept do at least.
As such ive purchased a grom pcv. It has a patch loom which plugs inbetween stock ecu and harness. As long as all wires are patched across and it intercepts the fuel inj, 2 crank wires, tps, ign. It should work.
The grom inj has the same imp and voltage.
The grom also has the same issue with the stock ecu controlling afrs 0-60% throttle. The 2 things they do to work around it is the dunojet wideband 2. It can simulate a modified narrow band signal to your stock ecu to give a 13.5afr.
The other is even cheaper. An EFIE which is stand alone and intercepts and modifies the O2 signal. O2 sensor on the Grom and piggyback tuners - Page 9
As the stock ecu runs rich enough in open loop +80% just putting in the EFIE will richen up your afrs in the closed loop area. Tho you'd need a wideband to know how much etc and set it up correctly.
One more thing. They have found the stock ecu is quite capable of running a larger inj. It will adjust to pull your afrs back done.
Anyhow. Wish me luck with the pcv. I want ign control.