Basics

S3 EFI
An Electronic Fuel Injection System Developed by Robot Cantina (YouTube Channel) / Jimbo that is based off of the Bosch CIS System
- It is somewhat in-between a “dumb” Carburetor system, and a modern “smart” system like a Speeduino with tons of sensors / Dual Injection etc
Low Complexity/Points of Failure, but just smart enough to work reliably is the design goal
As per3:36 in the video,
It DOESN’T HAVE:
- A Crankshaft Position Sensor
- A Throttle Position Sensor
- An Air Intake Temperature Sensor
- Oxygen Sensor
  - This MAY be useful enough to add in in their opinion
It DOES Have:
- A Manifold Absolute Pressure Sensor
- A Thermal Time Switch ( Thermal Fuse ? ) for Cold Start detection+adjustments
- A Delay Based Startup Enrichment
The stock Carburetor is kept as a Throttle Body
- Unless you want to remove that restriction and use a dedicated throttle body and Port Fuel Injection etc

Components

An Amazon Listing for the Kohler EFI Fuel Pump Module ( ~57 USD as of this edit’’’ )
- As per 5:38 in the video, you are not supposed to gravity feed these pumps
- It needs a Diaphragm Pump based low pressure pump to go from fuel tank to it’s low pressure fuel inlet

An Amazon Listing for “GY6 Clone” ( ‘’’~28 USD as of this edit’’’ )
- ” Perfect Fit: Designed as an OEM replacement, this RedCap fuel injector provides a precise fit for Jonway GTX 250, Cougar Cycle Clash Force 200 EFI, Gator 200-Tank, and other scooters or motorcycles with XMT 250 EFI GY6 168cc, 170cc, and 200cc engines, ensuring seamless integration and reliable performance.”
- Mentions EV1 Fuel Injector style wire connections?