The revolutionary new KS-4 is Phormula’s most advanced knock detection system yet. Offering all the great functionality of the KS-3 but also a fully configurable 0-5v output and a remote alarm function that allows the KS-4 to trigger a remote warning system.
Optional twin sensor kit available for V6, V8 and Boxer engines
The KS-4 contains the functionality of the KS-3 plus:
0-5v analogue output
The KS-4 contains a true 0-5v analogue output. Data output rates are configurable at up to a blistering 100 samples per second and compatible with all Data Logging Software that can accept a 0-5v input; Engine Dyno’s, Rolling Roads and ECU’s. The 0-5v output can be integrated with an ECU to provide closed loop knock control.
A sample logworks trace:
The KS-4 external trigger function adds further flexibility by allowing you to power your own external warning devices when the KS-4 alarm is triggered.
The signal from the sensor can be easily routed to another location within the vehicle. This can provide a more convenient location for the interface to the Knock Analyser Pro.
How does it work ?
The KS-4 monitors engine knock levels and can be configured to alert the driver via a visual, audable or external warning device. The KS-4 can be used as a hand-held device or permanently mounted to the dashboard. The KS-4 is configurable for frequencies between 6 and 9 kHz. The system includes high quality Bosch Wideband Knock Sensor, Sensor Plug, Shielded Signal Cable, Mounting Kit and Wiring loom.
The KS-4 has been designed to be very quick to install. The KS-4 comes as a complete kit containing everything necessary for the installation. A high quality Bosch knock sensor is included and is linked to the main unit via a high quality shielded signal cable. Installation is very simple: Mount the sensor, connnect the signal cable and connect the power supply.
What is knock ?
Knocking or detonation occurs when unburnt fuel in the combustion chamber explodes instead of burning in a controlled manner. When engine knock is occuring the pressure in the combustion chamber rises dramatically to levels that can destroy engine components in a few seconds.
What does engine knock sound like ?
If you watch the demonstration video at the foot of this page it gives you a good example of the sound of knock (as heard though knock monitoring device like KS-Pro) as well as showing you how to set the basic alarm threshold and some other paramaters.
The KS-4 is very simple to configure. The most common question we are asked is what frequency should I select. The frequency of knock is largely dependant on engine bore diamater. The following table is a good rule of thumb and should be adequate to set the KS-4:
65 mm — 8.8 KHz
70 mm — 8.2 KHz
75 mm — 7.6 KHz
80 mm — 7.5 KHz
85 mm — 6.7 KHz
90 mm — 6.4 KHz
95 mm — 6.0 KHz
“The development of the new KS-4 has been a welcome addition to the Phormula product range. Coupled with an ECU with an analogue input, it has enabled accurate logging of knock events that mean we can correlate those events with those heard on the det cans.”
– Paul Blamire – Zen Performance
Demonstration including the sound of knock: