Listen for knock, not noise
As a professional tuner, effective knock detection is the single most critical aspect of tuning any motor - particularly in highly stressed, high boost applications. I have tried most of the knock detection products on the market over the last 8 years, and have found the KnockBlock to exceed the performance of the competition, while offering more features and a lower price.
For knock detection using the audio headphones, I found the KnockBlock allowed me to clearly isolate knock even on noisy engines. When used in conjunction with a G4 ECU, the KnockBlock can also provide active individual-cylinder knock control. We tested this function and found it to be easy to configure and highly effective, giving added peace of mind when tuning an engine on the edge.
In my professional opinion the KnockBlock offers a cost effective approach to knock detection, and since initially testing the unit I would not be without it. I have personally used the KnockBlock on everything from 100 kw road cars through to world-record holding 1200+ kw drag cars, and anything in between.
Andre Simon - Tuner
Knock Control Interface
The KnockBlock G4 can act as knock detection interface for Link G4 ECUs. The KnockBlock G4 connects directly with the knock sensor and provides the ECU with an accurate measurement of engine knock. The G4 ECU can then be configured for closed loop knock control, allowing the ignition timing to be advanced and retarded to maintain output power while protecting the engine.
Additionally, the supplied knock light can be mounted on the dash to provide the driver with a visible warning in the event of engine knock.
Note: Some detonation events may not "flash" due to particular engine harmonics, use the audio output for added security when tuning.
Knock Tuning Tool
The KnockBlock G4 can be used as a knock tuning tool. Connected to a correctly positioned knock sensor the KnockBlock G4 will provide a clear audio output with a crisp distinction between normal engine sounds and knock. This will allow the tuner to safely optimise ignition timing and mixtures when tuning an engine.
What is Knock?
Knock, also known as detonation or "pinging", refers to the spontaneous combustion of an air/fuel mixture inside the combustion chamber. Knocking is induced by excessive pressure within the combustion chamber causing the air/fuel mixture to self detonate. Excessive pressures can be a result of excessive engine temperature, excessive turbo boost pressure, excessive charge temperature and over-advanced ignition timing.
The reason engines get near the point of detonation is tuning for performance and efficiency. To achieve maximum output and efficiency from an engine, combustion pressures must be optimised to create the maximum force on the top of the piston (or side of rotary). This maximum combustion pressure is controlled by ignition timing.
When the air/fuel charge detonates, a large sharp pressure impulse is created which vibrates the surrounding engine structure. The effects of the vibrations range from no damage to severe engine damage. This gives the need to accurately detect engine knock.
The most common way of detecting engine knock is to bolt a piezoelectric vibration transducer (knock sensor) to the side of the engine block. The knock sensor exhibits similar characteristics to an audio microphone but converts vibrations rather than audio to an electric signal.
Window operation refers to the window ECU interface. Once the G4 ECU has been configured to work in this mode, it will issue an active low pulse to the KnockBlock G4's window input. This low pulse will be the duration of when knock is expected to occur for a particular cylinder. During this low pulse the KnockBlock G4 actively measures engine knock. On completion the KnockBlock G4 digitally returns the knock level to the ECU via its window output. The ECU will then process this information and display and act upon the level of knock for each cylinder.
Active noise cancellation has no effect on window operation.
Knock sensor interface for use with headphones or direct ECU connection
High power, low distortion audio output
ANC (active noise cancellation) detection mode
40MHz digital signal micro-processor
Analogue 0V to 5V output for interfacing to a Dyno or Engine Management System
Digital time window input for individual cylinder knock control
Digital window output for interfacing to Link's G4 ECUs
External knock indication LED
Fifteen user selectable digital filters
Selectable detection gain from 1 to 64
Internal 9V battery compartment for quick setup
Low power mode for extended battery life (audio only)
- 120mm x 80mm x 25mm
- 8V to 18V supply input range
- 160g with 9V battery
The KnockBlock G4 is available in two forms - a complete toolbox with headphones, battery KnockBlock, sensor and looms, all in a custom carry case or KnockBlock only.
If you are fitting the KnockBlock permanently to a engine for closed loop, windowed individual cylinder knock then the KnockBlock kit is for you. The kit ships with a KnockBlock and loom and is priced very competitively.
If you are a tuner then the toolbox is the essential purchase with everything that you need to get into some serious tuning.
Link Engine Management Knock Control uses a block mounted, piezoelectric microphone (knock sensors) to "listen" for abnormal engine noise / vibrations which occur when the engine detonates (knocks).
All looms are available individually as replacements. As many KnockBlocks are in use daily looms will deteriorate and it is recommended for signal integrity that looms are inspected regularly for physical damage. Contact you local dealer.
Knock Sensor Plugs (connectors)
Available from your Link distributor.