Monitoring knock with SAFC Neo

[mhuffman]

Hey all,

I got the SAFC Neo. I like it alot. Didn't feel like buying a used SAFC-II.

Anyways, the only drawback i see is not having an integrated knock monitor. Has anyone tried to use one of the unused wires from the Neo to monitor knock, similar to the blue wire mod (which i have elected not to do)?

Thanks,
Matt

 

[steve]

It sounds like your thinking that the knock sensor output is the knock level. It's not, it's just a microphone that the ECU processes to listen for the sounds of knock and the times when the engine could knock.

The "knock monitoring" that the SAFC II does is just comparing the trained noise levels at various RPM from the current noise levels. Not even worth connecting the wire up for since it doesn't tell you what the ECU is seeing.

 

[mhuffman]

It sounds like your thinking that the knock sensor output is the knock level. It's not, it's just a microphone that the ECU processes to listen for the sounds of knock and the times when the engine could knock.

The "knock monitoring" that the SAFC II does is just comparing the trained noise levels at various RPM from the current noise levels. Not even worth connecting the wire up for since it doesn't tell you what the ECU is seeing.

Ok. I wasn't sure how the old SAFC-II reads "knock" anyways.

How does the Palm datalogger read the 'knock'?

 

[Zmann42087]

Ok. I wasn't sure how the old SAFC-II reads "knock" anyways.

How does the Palm datalogger read the 'knock'?

counts of knock. Have a look here.

Note that only first-gen's can log knock from a pocketlogger. 2g's can't.

 

[steve]

Note that only first-gen's can log knock from a pocketlogger. 2g's can't.

Not using the OBD 2 interface. I haven't looked to see if it can using the MUT interface.

 

[spyderturbo007]

Yeah, apparently it can using the MUT interface. Ceddy has written a program, which for right now works with '98 & '99 ECU's, which allows you to log knock. Pretty cool stuff.

 

[twdorris]

Have a look here.

That page is misleading. "Knock sum" (I hate that name) is scaled timing retard. Those conditions presented on that page have nothing to do *directly* with ignition advance. They have to do with long term octane updates (the weighting factor used to interpolate between the good and bad octane tables).

So when that page says "3 or below, the ECU will advance timing" it doesn't really mean "timing". It really means the ECU will attempt to increase its idea of fuel octane under certain conditions. Ignition advance is updated immediately and always as a result of a non-zero knock sum value.

Thomas Dorris

 

[knochgoon24]

Yeah, apparently it can using the MUT interface. Ceddy has written a program, which for right now works with '98 & '99 ECU's, which allows you to log knock. Pretty cool stuff.

I actually had it work on my 4/97 build Talon.