Knock Sensor

[RanRan]

I'd like to hook up a knock sensor. It's basically just an on/off switch. I am thinking that wiring to the canopy open/close sensor might make sense.

The reasons for this are:
1. New fuel on the horizon
2. I can't hear a knock any other way
3. The sensors (just one is needed) are very light and can sense a knock on any cylinder.

I brought this topic up on the CubCrafter's forum. This seems like an essential to me.

Example: leaned out, starting a climb on a hot day, the engine starts beating itself up and I CAN'T HEAR IT.

What do you think?

 

[dynonsupport]

Knock sensors are not on/off switches by themselves. They are microphones that require processing to determine if the noise they are hearing is knock or not. Some microphones are mechanically tuned to the knock sound and require minimal processing while others require complex computer processing to sense the knock above the background noise.

The EMS cannot process this by itself. What is the output from the processor box that you are thinking of using? The automotive processors I am used to output a very short pulse each time they get knock, which may be too short for the EMS to react to, and even if it does it will likely be cleared by the time you look at the screen. If it outputs a long pulse or something that needs to be manually reset, then this might work with the EMS. If it outputs a voltage that increases with more knock, the SkyView could display this as a increasing bar or warning light as well.

 

[RanRan]

It is a 'microphone' sensing a narrow frequency of sound through the metal of the engine. i.e. a knock is a knock and not, say, a noisy tappet which it will not hear.

Perhaps a thermo sensor lead would work better as one could set a red zone to pick up the knock but not minor pings.

I'll do some checking here in Motown to see how their auto computers process the signal.

 

[dynonsupport]

We already read CHT and EGT's, both of which give you a lot of information about any kind of long term knock.

 

[RanRan]

True, but I still can't be certain the engine is knocking because I can't hear it. I just want to add this one thing for ME.