fast951

After a long time in the work, it’s finally here. I would like to introduce the new Vitesse Visual Knock (V-KNOCK™).

Bad fuel, heat, heat soaked engine, tuning, too much boost can cause engine Knock. You car’s ECU detects engine knock and it generates Knock Indicators.
The Knock Indicators have a very short duration, in the millisecond range, requiring special equipment to capture. In some cases, through the OBD interface or with aftermarket components, the user can get the knock count. Good information to know, but it’s after the fact.
Engine Knock is damaging! It’s important to know when it happens the moment it does! If you don’t know when your engine is knocking, how can you address the problem?

V-KNOCK™ works in conjunction with your car’s ECU to alert you the moment engine knock is detected.
When V-KNOCK™ detects a knock indicator; it generates a visual alert, and a Data Logger signal. Each has an adjustable duration.

V-KNOCK™ allows you to set a threshold above which you are interested in monitoring alerts. Suppose you are interested in alerts over a certain boost level, or over a throttle position angle. You have the flexibility!

Installation can be as simple as hooking up a few wires and a LED. Or you can interface it to a Data Logger or a PiggyBack to alter the tuning parameters.

V-KNOCK™ supports the following car models: 964, 993, 951, 944S, 944S2, and 968. More models will be added soon.

Detailed instructions (per car model) are provided to make installation a simple process.

For more information and to take advantage of our introductory offer, please visit our website. Just click V-KNOCK™

BLACK-BETTY

Does this work with Motec M84?

fast951

V-KNOCK is designed to work with the 964 factory DME.

It has been many years since I used Motec, without the Motec M48 documents, I cannot answer you. If you have the Motec documents (Installation or specifications), email them to me, I'll take a look and let you know.

Sire

Jeff i got youre piggy back is it worthfull for me to instal v-knock?

VT DRIVER

Can you please explain what "knock" is and why it is important to detect. Thanks.

fast951

Hi Marco,

Yes it will be beneficial to add V-KNOCK, especially if you have the PiggyBack..

V-KNOCK alerts you that Knock is being detected by the DME. When used with the PB, you are able to:
- Data Log engine parameters and when knock occurs.
- Program the PB to alter ignition and/or fuel to handle knock.

V-KNOCK, DME and PB all work together.

When the DME detects engine knock, it may retard ignition as much as 4,5 or 6 degrees. It helps save the engine, but it hurts performance.

If you have a consistent knock activity under certain engine conditions (ex. 5300RPM under full load), you are able to tune with your PB to target a particular area. By doing so, you eliminate knock before it happens.

In the PB, you can be proactive, you may need to retard ignition 1 or 2 deg to eliminate knock. (Instead of the DME pulling 3,4 or 5..). You got rid of knock and you may gain performance in the process.

Of course, there will be the erratic knock signal, which you can handle in the PB as well. The duration of the knock handling in the PB is user adjustable via V-Knock.

On air cooled engines, you have a noise factor to deal with. At times, you may get knock signals between gear shifts. With V-Knock, there is a way to define which signals you are interested in.


Hope this helps.
John

Sire

Hi Jeff,
Oke do you know wich type piggy i got?

fast951

Describing engine knock, and how it could cause damage can be a very lengthy post. Instead, a web search on "Engine Knock" will yield all sort of information.

A high level description can be found on wikipedia

fast951

It's John not Jeff.

I do remember which PB you have . You have the VRPB6.

Please Contact me directly with questions unique to your setup.

NineMeister

No.

From the description of the product, it uses the knock detection output signal from the Motronic which is sent out to the round OBD port, hence using the Motronic's inbuilt knock detection functions. The Motec M84 does not have this circuitry therefore it would not work. If you are worried about knock on a Motec system and would like a visual display there are suitable simple systems available which will work with the stock 964 knock sensors.

aj986s

Engine "knock" is sometimes referred to as "pinging" or "detonation" or "pre-ignition".

Its basically an explosion that occures in the combustion chamber that shouldn't actually be there. Normally, in an internal combustion engine, when the piston rises up during the compression stroke (both valves closed), the spark plug fires igniting the air-fuel mixture. What's supposed to happen is that the air-fuel mix starts burning at the spark plug, and proceeds across the piston as a flame-front. As the air-fuel burns, the temp increases and raises the pressure in the cylinder, which then helps push the cylinder on the downstroke, creating power. Here's a nice graphic showing the process. And of course this process is happening very quickly; the combustion process in a single cylinder happens in milliseconds.

However, sometimes as the pressure is increasing while the flame front is moving across the cylinder, it can increase to the point where air-fuel on the far side of the cylinder overheats and spontaneously ignites. The undesirable "explosion" is called knocking/pinging/etc. If it happens often enough, it can cause damage, including boring a hole through the piston.


It can be caused by a variety of things. If timing is too far advanced (spark plug fires too early) it can cause knocking, because pressure increases from the flame front starting too soon on the upstroke. Sometimes carbon deposits in a cylinder can create a "hot spot" that acts like a 2nd spark plug, igniting air-fuel at the wrong time/place. And octane rating of the gas has an effect on the process; higher octane fuels are more resistant to knocking. They allow the air-fuel to reach a higher pressure before spontaneously combusting. Performance engines with higher compression ratios (ie more pressure in the cylinder) require higher octane fuels to run properly.

Lots more info online.

Modern engines have knock sensors which respond to knocking by retarding the timing, causing the spark plug to fire a bit later, which reduces the eventual pressure generated in the cylinder before starting its down stroke. But retarded timing can lead to reduced power.

fast951

Thank you for clarifying.

Quadcammer

Ok, so on my 993 turbo, this led would come on when the motronic initiates knock retard? Or would it come on as soon as there is any signal from the knock sensors?

can you post some bigger pics of the whole deal including the leds.

thanks.

fast951

The factory DME has software filters to deal with noise. It knows when to look for engine knock. Not every Knock Sensor pulse is considered engine knock.

When the DME detects engine knock (or what it considers as engine knock), it tries to handle it. It may retard ignition, alter fuel or lower boost. It also generates a knock indicator, wich can have a very short duration.

We do not monitor the actions taken by the DME to control knock. We just let the DME tell us when knock occurs, then we relay the info so you are aware of it via a LED or a data logger signal.

I tried uploading a few pictures, for you, but no success. RL is not cooperating.
The LEDs we provide are very bright, one RED and the second is BLUE. If you prefer to use your own LEDs, that's not a problem. I understand some people do like to keep a certain look inside the cockpit.

V-KNOCK module is fairly small, approx 2"x1" + wires.