Engine Knock (detonation, spark knock, pinging) occurs when the combustion of the air and fuel mixture in the cylinder occurs before the spark plug ignites it. The problem with this, is that the pressure resulting from this combustion (and associated pressures resulting from it) happens as the piston is still moving upward against the pressure pushing down. This shockwave can be very damaging to the engine. Although bad knocking is audible, your engine is knocking far before you hear it.
When you increase the pressures inside the cylinders (by increasing the compression ratio, or by supercharging or turbocharging), you increase the propensity for knock. What can be done to reduce knock?
- The use of a fuel with high octane ratings increase the combustion temperature of the fuel, reducing the proclivity to detonate. This is why high-performance engines require higher octane fuels.
- Enriching the air-fuel ratio reduces the combustion temperatures and increases the margin above detonation.
- Retarding ignition timing delays the timing of when pressure builds from the ignition event.
Most all new vehicles built-in knock sensors that the computers use to automatically adjust ignition timing to maintain the best safe power given the fuel grade that being used.
What happens if you vehicle is knocking but lacks a knock sensor? It has no way to know if the engine is experiencing knock and damage will most-likely occur.
Our tunes are calibrated conservatively for vehicles running premium fuel. This can be 91 or 93 depending on what altitude you are at (lower altitudes require 93 as premium due to the increased air density, and therefor cylinder pressures, at those altitudes). What does this mean? This means there is power left on the table, in the interest of being safer.
What KnockLink can do for you:
- It can allow you to more safely run a higher boost pulley.
- It can allow you to advance your timing to increase your performance and efficiency without having to guess if your engine is knocking.
- It can notify you if your engine is knocking far before you hear it.
- It can indicate if your fuel octane is not adequate. (just because the pump says ‘Premium’ doesn’t mean someone didn’t make a mistake and put a lower octane fuel in the fuel station tank).
The KnockLink G4 Digital Warning is the only self calibrating, knock warning instrument on the market. The KnockLink G4 won a SEMA 2011 media award for best new product.
The KnockLink G4 is designed for both street and race use and is the only device on the market that requires no setup. Other systems require time consuming gain, frequency and noise settings to be adjusted. Without proper knock listening tools, this can prove difficult if not impossible. The KnockLink G4 requires none of this, just bolt the sensor to the engine block, wire it in, and start the engine.
Even light detonation will damage an engine over time. The G4 KnockLink’s microprocessor continuously scans the knock signal and warns for any knock occurring. The engine’s RPM and load is automatically 3D profiled by the KnockLink G4, continuously storing and dynamically adjusting this noise profile map while looking for the particular knock frequency.
Operation is simple. The color of the LED represents four different modes:
- Dim Blue – KnockLink is powered, waiting for the engine to be started
- Flashing Blue – KnockLink has detected the engine has started and is now calibrating
- Dim Green – KnockLink is adapting to the engine’s noise profile and listening for knock
- Flashing Red – KnockLink has detected knock. Avoid large throttle openings, seek professional advice