RaceCapturePro Sensors

Sensors

Temperature Sensors
GM-Style
Mfg / Part #	Image	Pigtail	Mechanical	Notes	Analog Channel Configuration
Wells SU109 SMP TX3 Pigtail: Pico 5615pt			3/8" NPT threaded brass body and a 2 pin terminal.	Can be used for air inlet temperature for normally aspirated engine	Using 2.2K pullup resistor Preset available in the RaceCapture app
Wells SU107 SMP AX1 Pigtail: Pico 5616pt			3/8" NPT threaded brass body and a 2 pin terminal.	Use for measuring air inlet temperature. Exposed sensing element, necessary for boosted engines where fast response times are necessary. Due to the fragility of the sensing bulb, it is necessary to pot the base of the sensor leads with sensor-safe silicone when used in high vibration environments.
AEM
Delphi 12160855 equivalent AEM-30-2012 Equivalent			Extended temperature range - suitable for coolant and oil 1/8" NPT Plug set and pins are included with kit	Compact form factor is appealing Specifications Sheet	Using 2.2K pullup resistor Preset available in the RaceCapture app
Infrared Sensors
Mfg / Part #	Image	Notes
Thermocouple Sensors
Mfg / Part #	Image	Notes
Pressure Sensors
Fluid Pressure
These sensors are appropriate for measuring fluid pressures in an engine. Not appropriate for measuring manifold boost or vacuum as these are relative pressure sensors. Use an absolute pressure sensor instead.
Mfg / Part #	Image	Pigtail	Mechanical	Notes	Analog Channel Configuration
AEM 30-2131-150		3 pin GM connector	1/8" NPT	150 PSI pressure sensor, appropriate for oil and fuel. Linear response with an output between 0.5v and 4.5v Technical Specifications Default kit from AEM includes pigtail	Since these type of sensors have a linear output, replace the 4.5v value with the max pressure of the device in the units you prefer. e.g. 10 bar, 150 psi, etc. Repeat the value through the rest of the calibration table. Volts Scaled Value (PSI) 0.5 0.0 4.5 150.0 4.5 150.0 4.5 150.0 4.5 150.0
Various		3 pin GM connector	1/8" NPT port	10 bar (145 PSI) stainless steel pressure sensor. Linear response with an output between 0.5v and 4.5v Other sensor ranges are possible - e.g. 10, 30, 150 bar, with a consistent linear output.
Manifold Pressure (MAP) Sensors
Sensor: 12223861 (GM) Pigtail: 15305891 (GM) PT1035 (AC Delco)			Bracket for firewall mounting vacuum port	3 bar MAP sensor	Volts Manifold Pressure (KPa) 0 3.6 1.25 80.0 2.5 159 3.75 237 5.0 315.0
Freescale MXP4250AP				2.5 bar MAP sensor An extremely popular MAP sensor used in the Megajolt ignition and Megasquirt fuel injection systems. Can be used in a simple circuit and powered by the 5v voltage reference from Race Capture
Tire Pressure
Mfg / Part #	Image	Notes
Schrader		OEM TMPS System Schrader TPMS receiver outputs tire pressure data on the CAN bus. would need to reverse engineer CAN bus protocol. Analysis / Reverse engineering work queued
Pulse/Speed/RPM Sensors
RPM
Mfg / Part #	Image	Notes
Autosport Labs CoilX		The CoilX sensor module is designed to safely interface the noisy, high voltage RPM signal at the ignition coil pack primary into a clean signal that RaceCapture/Pro can process. CoilX Project Information Page
Wheel Speed / Gear speed
Hall effect speed sensors will require an external 1K pull-up resistor, connected to 5v. This can be wired up near the sensor connection for convenience.
Mfg / Part #	Image	Notes			Pulse Channel Configuration
Hamlin 55505		Simple 3 wire hookup - No external pullup resistor required Rugged Hall effect sensor suitable for harsh automotive environments (fuels, solvents, lubricants) -40 to 125c operation Technical Specifications			Configure the pulse channel with the number of pulses per revolution, which maps to the number of teeth on the gear / wheel.
Cherry GS100701		Low profile, aluminum body, flying leads -40 to 125c operation Technical Specifications
Distance Sensors
Ride Height
Mfg / Part #	Image	Pigtail	Notes		Analog Channel Configuration
Sharp GP2D12			Optical distance sensor - 10 to 80cm range 3-pin connector, analog output Possible uses include ride height position (pointed at ground) and pedal position Technical Specifications		Steps to calibrate: After installation place the vehicle on a level surface. Set the Analog calibration to 0-5v simple linear scaling At rest, note the voltage of the sensor. This is the zero level. Raise and safely support the corner of the vehicle and remove the spring. Move the suspension arm to full droop. Note actual inches / mm traveled and also note the voltage logged by RaceCapture/Pro Move the suspension arm to full compression. Note actual inches / mm and also note the voltage logged by RaceCapture/Pro Create Calibration Table: Place the droop voltage / distance combination into the 1st column of the calibration table. Make the distance negative Place the 'at rest' voltage into the 2nd column of the calibration table. Make the distance zero Place the compression voltage / distance into the 3rd column of the calibration table. Make the distance positive Repeat the compression voltage / distance values for the 4th and 5th columns.
BMW 37140141444 Pigtail: 61138383300			5v power supply Approximately 0-5v output Measures distance over 90 degrees of the arm travel. Used as a ride-height sensor for BMW and Mini applications for auto-leveling headlights
Texense RHS			Infrared Ride Height Sensor 12-16v supply 0-5v output Technical Specifications
KA Sensors RHL3			Laser Ride Height Sensor 11-30v supply - separate power supply required 1-5v output Technical Specifications
Various Mfg / String Potentiometer			String Potentiometers can be used for a variety of purposes: Linear, distance, and rotation (if cable is wrapped around a shaft) Wiring Information
Angle / Rotation Sensors
Throttle Position (TPS)
Mfg / Part #	Image	Pigtail	Mechanical	Notes	Analog Channel Configuration
Ford / SMP TH45			Screw mounted, keyed input for throttle shaft	Common Ford style Throttle Position sensor	To calibrate, note the voltage at 0% throttle and then at 100% throttle. Use these two numbers to create a 2 point analog scaling map. Wiring Guide
Air / Fuel Ratio Sensors
Mfg / Part #	Image	Pigtail	Mechanical	Notes	Analog Channel Configuration
Texense LSU 4.9 Sensor		Built-in wiring	Screws into O2 sensor port	LSU 4.9 sensor	calibration Volts Scaled (AFR) 0.004 8.4 1.36 11.3 2.3 14.0 2.879 18.4 3.395 26.7

Wiring Analog Sensors

RaceCapture/Pro Analog Input Specifications

• RaceCapture/Pro has 8 analog inputs; the 8th input is wired internally to measuring battery voltage.
• Analog input range is 0 - 5v
• Input Impedance: over 1 meg ohm

Calibrating an Analog Sensor

Refer to your sensor's data sheet for the sensor's calibration curve.

Linear Sensors

A linear sensor may specify two voltages/value pairs representing a low and high range for the sensor. A straight line is drawn between the points on the sensor.

Example: 150 PSI pressure sensor

• 0.5 v = 0 PSI
• 4.5 v = 150 PSI

In the Analog Channel configuration, select the "'Mapped"' sensor mode, and then enter the values into the interpolated mapping grid.

• For column 1, enter the low voltage range in the Volts cell, and the low scaled value in the Scaled cell.
• For columns 2-5 enter the high voltage range in the Volts cell, and the high scaled value in the Scaled cell

Curved Sensors

These are often seen with thermistor based temperature sensors, where the response is not a straight line, but a curve. Multiple points can be used to sufficiently approximate the curve.

• Note: RaceCapture will linearly interpolate the scaled values between the sensor points, so value transitions will be smooth.

Example: Extended Range temperature sensor with 5v reference and 2.2K pullup resistor

• 0.4 v = 302 F
• 0.87 v = 239 F
• 1.88 v = 176 F
• 3.2 v = 122 F
• 4.72 v = 32 F

In the Analog Channel configuration, select the Mapped sensor mode, and then enter the values into the interpolated mapping grid.

• Note: If you have more than 5 points for the curve, spread the selection of points evenly between your low and high range.

Types of Sensors

Temperature Sensor

Temperature sensors are passive devices that measure temperature through the use of a thermistor, a resistor that varies resistance with temperature.

We recommend using dedicated, two wire ECU-style sensor similar to the types specified in our recommended sensor list for best results.

Pullup resistor

A pullup resistor is needed to create the necessary voltage divider circuit so RaceCapture/Pro's analog input can measure temperature as a varying voltage. This pullup resistor is connected to the 5v reference on the RaceCapture/Pro terminal block.

High Resistance ECU style sensors

Use a 2.2K ohm pull-up resistor for high resistance ECU style sensors, such as the temperature sensors in the supported list

Low Resistance Gauge type sensors

Low resistance gauge type sensors are not recommended. If you must use one of these types of sensors, a 1/4 watt 220 ohm pull-up resistor can be used for sensors such as VDO 323-095, 325-002 and similar.

Sensor Ground

Two wire ECU style temperature sensors have one sense lead and one ground lead. For best accuracy, connect the ground lead to the same ground point as RaceCapture/Pro.

One wire gauge type sensors have the ground as the body of the sensor. Ensure the engine is properly grounded to the chassis via multiple ground straps.

Active Sensors

Active sensors are powered devices that provide a variable voltage output related to the environment being measured- such as pressure, distance, temperature, speed, force, etc.

Active sensors are particularly easy to wire. Nearly all active sensors for automotive applications specify 5v power and produce an output within 0 to 5v, making them directly compatible with RaceCapture/Pro. Most active sensors have a linear output and therefore are very easy to calibrate.

Steps for connecting an active sensor

1. Identify the power, ground and output signal wires. The sensor technical documentation will provide this information.
2. Connect the sensor ground to the same location as the ground point for RaceCapture/Pro
3. If the sensor is 5v powered, connect it to the 5v voltage reference on RaceCapture/Pro
4. Connect the sensor output signal to the desired analog input port of RaceCapture/Pro

Wheel Speed / Hall Effect Sensor

Wheel speed sensors generate a series of pulses as a toothed wheel passes by the face of the sensor. We recommend hall-effect style sensors, and these are provided with 3 connections:

• Power
• Ground
• Signal Output

Note: - We do not recommend using 2 wire Variable Reluctance (VR) type sensors. VR Sensors will require a conditioning circuit before being provided to the inputs of RaceCapture/Pro.

Wiring the Speed Sensor

• Power: Connect the sensor's power to the 5v Vref on RaceCapture/Pro
• Ground: Connect the sensor's ground connection to the ground shared by RaceCapture/Pro
• Sensor Output: Connect the Sensor Output to one of RaceCapture/Pro's timer input channels

Optional pull up resistor

RaceCapture/Pro requires both a voltage and ground pulse provided in the waveform provided by the sensor. Most sensors provide an internal pull-up resistor so an active square wave can be observed on the output. However, some sensors only switch ground and leave the output line in a high impedance state when not active, like opening and closing a mechanical switch. If the sensor does not provide a pull-up resistor the wheel speed signal may have noise and glitches which may be observed as high value glitches in the dashboard and log file data.

If it's determined a pull-up resistor is needed:

• Use 2.2 to 10K pull-up resistor can be added close to RaceCapture/Pro to ensure a clear signal
• You can use the SensorX breakout board to conveniently wire this pull-up resistor

Throttle Position / Variable Resistors (Potentiometers) / Linear sensors

These type of sensors are passive devices comprising some form of a variable resistor. Examples include:

• Throttle Position Sensors
• Linear sensors
• String Potentiometers
• Single and multi-turn Potentiometers
• Fuel Level Sensors

Standard Variable Resistor (Potentiometer)

These are typically found in Throttle Position Sensors (TPS), string potentiometers, and linear sensors.

1. Consult the sensor's technical documentation for sensor connections.
2. Connect one of the outside legs of the variable resistor to the ground point for RaceCapture/Pro
3. Connect the opposite leg of the variable resistor to the 5v Vref of RaceCapture/Pro
4. Connect the variable resistor wiper (typically the center lead) to the the desired analog input port of RaceCapture/Pro

During calibration, if the sensor reads backwards, flip the 5v and ground connections.

Fuel Level Sensors

Also a variable resistor, these provide a variable resistance based on the level of the float.

Wiring

Determine if you need a pullup resistor, or if you are tapping into an existing circuit with a gauge.

If you already have a gauge connected

You will not need a pullup resistor - the gauge's internal circuitry already provides one. You will only need to tap into the existing signal feeding the fuel gauge sender. Jump to the calibration process below.

• Note you will need to ensure the sender does not exceed 5v during calibration. if it does, you will need an additional voltage divider to scale the voltage down to 0-5v required by the RaceCapture input.

If you have no gauge / you want to only use RaceCapture for your dashboard gauge

If you only have the sender and want to directly integrate with RaceCapture's analog input, follow this procedure.

• Choose a pull-up resistor value based on the the sender's ohm range. If it is less than 1000 ohms, then choose a 1000 (1K) ohm resistor as your pull-up. If the sender range is higher than 1000 ohms, choose a 2.2K resistor.
  • Rule of thumb - choose a resistor that is about 2X to 4X the maximum resistance of the sender.
  • A 1/2 watt, 1% accuracy resistor is recommended.

• Wire up the sender per the diagram:
  • Connect the ground of the fuel level sender to ground (ideally the same ground point used by RaceCapture)
  • Connect the output of the sender to one of RaceCapture's analog inputs
  • Connect the pullup resistor between +5v reference and the sender's output. This creates the voltage divider circuit which will present RaceCapture with a variable voltage depending on fuel level.

Calibration

With the fuel at different levels, measure and note the voltage present at the RaceCapture analog input for different fuel levels:

• Empty (0%)
• 1/4 (25%)
• 1/2 (50%)
• 3/4 (75%)
• Full (100%)

Set up the Analog Channel

• Choose an available analog input for your Fuel Level channel, then select the basic fuel level preset by selecting FuelLevel in the dropdown list.
  • This pre-sets the units (%), logging precision and min / max values. You can edit this by pressing the gear button next to the channel name.

• Set the sample rate to 1Hz.

• Set the mode to Mapped. This will let you create a curved mapping for the sensor voltage.

• Set the smoothing to Maximum - this will help account for variances due to fuel slosh.

• Enter the mapped values noted in the calibration process into the Analog Channel mapping editor under RaceCapture setup. This will provide the calibration curve for your fuel tank.

• Write these settings back to RaceCapture and observe your fuel level readings in units of percentage.

Example BMW E36 fuel level mapping

Example BMW E36 Fuel curve mapping (your sender's calibration will be different)

Sensor Breakout Board

SensorX is a breakout / distribution board that will make it easier to use sensors that require pullup resistors as well as making available multiple ground and 5V Vref connections. The built-in pullup resistors are easily disabled by breaking a designated trace on the board. This board is compact; enough to be bundled inline with your wiring harness and covered in heat shrink tubing when complete.

Sensor X instructions