Knock knock. Who’s there? Your blown engine. The four-cycle combustion engine has come quite a long way in its evolution and thanks to technology; it has risen to a precise science. Although precision is great, it also leaves little margin for error, especially at extreme boost pressures and high engine speeds. There are any number of events that could occur which have the potential to cause damage to an engine. One of the worst events is engine knock, the not so silent killer of engines. Like high blood pressure and some forms of cancer, early detection of knock can be treated with proper engine management tuning to ensure a healthy, strong, and long-lived engine.
Text by Richard Fong // Photos by Jun Chen and Richard Fong
KNOCK: THE GREAT EVIL
What is knock? Engine knock or detonation is the combustion of anywhere from one to multiple pockets of unburnt air-fuel mixture that occurs outside of the planned combustion window. When this occurs, the mistimed explosion sends a potentially devastating shockwave and increased cylinder pressures. The result of such an event could be anything from accelerated wear in the combustion chambers to a catastrophic engine failure.
TAG TEAM TUNING
Engine management tuners rely on two key variables when tuning an engine, the air-fuel ratio and the detection of knock. A proper wideband meter will monitor air-fuel ratios to ensure that an ideal quantity of fuel is being combusted for the volume of air in the cylinder for combustion. It will also inform you when there is too much fuel or too little fuel. On the other hand, monitoring knock could be an indication of a number of other potential problems including high intake temperatures, ignition issues and bad fuel, to name a few.
So how is knock monitored and detected? Knock manifests itself as an audible “knocking” sound. However, to the untrained ear or in the case of higher engine speeds, knocking becomes very difficult to detect. Some factory ECUs utilize a donut-style knock sensor bolted to the block to detect knock. When knock is detected, the ECU will pull ignition timing to remedy any knock that is manifested. In the case of tuning for greater horsepower levels, a tuner will employ an engine stethescope or a stand-alone electronic knock monitoring system for tuning purposes. But none of these solutions help the vehicle owner monitor knock while driving on the street or the track. Enter the Gizzmo Electronics K-Lite Knock Monitoring Alert Light.
Gizzmo Electronics has long recognized the importance of knock detection, developing an accurate and sophisticated knock monitoring system, the KMon, in 2007. Based on this technology, Gizzmo Electronics has packaged the knock monitoring accuracy of the KMon into an affordable device the size of a AA battery, the Gizzmo Electronics K-Lite.
The simple-to-install K-Lite features dual processors, six LED lights, peak recall, and the ability to monitor up to 64 frequencies. Like the KMon, the K-Lite relies on a Bosch donut-style knock sensor bolted to the block. If an engine already has a donut knock sensor, just purchase a longer bolt and stack the K-Lite’s sensor atop the factory one. A two-wire harness joins the sensor to the K-Lite unit. Not only is the K-Lite small in size, it’s also small in price. With an MSRP of $199.00, it’s an affordable solution that no one should be without.
The K-Lite body utilizes a clean cylindrical design with bright LEDs recessed in the housing, creating a shroud around the lights. There is no visible button on the unit as the K-Lite features a touch sensor located beneath the “ZMO” of the Gizzmo logo screened onto the body. This virtual button is used to put the K-Lite into its calibration mode and also serves as the peak recall button. A pair of brackets is included to facilitate easy mounting to the dash or steering column.
FUNCTION AND FORM
The K-Lite serves and alerts in both the D’Garage Project Silvia as well as Project 240SX, the contenders in the KA vs. SR Battle. Given the aggressive tuning and the grueling battles that have yet to be waged, keeping track of engine knock is a must. With more testing on the dyno, the drag strip and the road course yet to be completed, ensuring these vehicles survive the competition is essential. With the K-Lite on duty, the chance of knock slipping by unnoticed is dramatically reduced.