hondata s300

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Staff member

s300 Overview

The s300 is a plug in module to the factory Honda Engine Computer (ECU) which vastly expands the capabilities of the factory ECU. Forced induction, datalogging, real time updating of parameters, engine protection are but a few of the s300 features.

s300 Pricing and Options

Price Description
$595 s300 with all features and software


Main features:

* Fits inside the ECU
* Built on the proven s100/s200 code base
* USB connection for speed and compatibility
* SManager Windows based software for parameter & table editing, calibration uploading and datalogging.
* Real-time updating of ECU
* Built in calibrations for common engine combinations
* Built in datalogging to a laptop
* On board datalogging memory (2 MB memory, 20-60 minutes datalogging)
* Adjustment for different sized injectors, with overall fuel trim.
* Configurable for any MAP sensor (to at 5 Bar and above)
* Engine protection from over boost and over temperature.
* Expanded fuel and ignition tables, both in rpm and load, to 60 lbs boost and 11,000 rpm (these are not the upper limits)
* Launch control with anti-lag
* Full throttle shift
* Two multi purpose outputs for nitrous control or similar
* Lambda tracing (with a wideband o2 sensor)

SManager editing software features:

* High and low speed 24 x 20 ignition and fuel tables for correct VTEC tuning
* Injector size fuel trim
* Fuel trim for starting, throttle tip in and individual cylinder trim
* Rev limiter with fuel cut or fuel and ignition cut
* Launch control with anti-lag
* Full throttle shift
* Adjustable VTEC window with load and throttle control
* Secondary intake runner control
* Adjustable idle speed
* MAP sensor type and calibration
* Adjustable boost cut with hot and cold settings
* Shift light
* Closed loop control
* Air temperature compensation
* Water temperature compensation
* Fuel and ignition correction based on gear
* A/C shutoff conditions
* Closed loop
* Two general purpose outputs for nitrous control, dual boost control or similar
* On board datalogging trigger conditions

The s300 uses different connecting pins in the ECU from the s100/s200, and also has a slot cut in the side for the USB connector, so the ECU must be modified for use with the s300. The s300 is made to fit in a full frame ECU case (US and most markets), so will not fit in a JDM ECU case.

USB Connection

The s300 uses a high speed USB connection for both programming calibrations and datalogging. No more USB/serial connectors!

Real-time Update

The s300 can be updated in real-time with the engine running without affecting the operation of the vehicle. This means that calibrations and changes can be uploaded to the ECU very quickly (2 seconds for a new calibration, a fraction of a second for anything else), without interrupting the operation of the engine. Changes made in the SManager software are uploaded to the ECU instantly and you can see the effect immediately. The s300 does not use an EEPROM or equivalent, so you never need to open the ECU to change chips nor 'burn' ROMs. No EPROM programmer is necessary - you just need a laptop with USB port.


The s300 has datalogging to the SManager software built in via the USB port. Using a laptop the various ECU sensors can be datalogged, viewed, graphed and saved for later analysis.

Additionally the s300 has on board flash memory which allows a datalog recordings to be made without a laptop, for later access and download to a laptop. Multiple recordings can be made and stored in the s300 for a total of around 40 minutes of total datalogging time. An external switch can be used to start and stop recordings, or engine conditions can trigger recording. For instance in a drag race, the s300 can be set to start recording once the rpm is bought up to near launch rpm and automatically stop once past the traps and the rpm drops below a certain level.

MAP Sensor Compatibility

Any linear MAP sensor can be used, using a scalar and offset to translate the MAP sensor characteristics into pressure. Popular MAP sensor settings are built in for easy of setup. To do this you will need the map sensor calibration numbers from the manufacturer of the sensor.

looks to be prety bad ass... i dunno... hondata may be on to somethign here... no more chips!!!!


Staff member
don't think so... pretty sure its still obd1 ecu's.

basically, its the k-flash, but made to work on the obd1 computer.