TheArchitect

>>Yes you will see more scatter and I am awre of that, Motec scatters some too.

No different than autronic.


>>Is it so specific that it is every individual engine that must be measured to find the specific frequency and window?

Not usually, but differences in bore/stroke camming and other items can mess with the noisiness and spectra of engine noise, as well as shifting the center freq of the knock itself.


>>Is it also necessary to have a cylinder specific sensor before it will work or can the ECU detect the frequency under the 4 different windows for each cylinder??

Not 100% sure what you are asking here.

It is necessary to only qualify potential knock spectra when each of the 4 cyls are in the ignition range timing of their cycle. One sensor is usually sufficient to "hear" knock on all 4, "V" engines could stand to have one on each bank.



>>I would love to be involved in working this out and will use my resources to help it happen.

I'll keep this in mind, always good to have friends in the right places.



>>I would like to communicate with you some more as I want to put into place a set routine to use when we do dyno time.

Sure, I'll email you.



>>I will be using Mark Swanson for tuning this time.

That sounds like a good choice, I've heard good things of his tunes. Quality dyno time is the best money spent on street driven car.

A400

"Having more teeth on the timing wheel (and using every one of them) allows you to minimize timing errors related to variation in rate. The frosting on the top of the cake is having enough processing power to detect and compensate for repeatable variations in rotational rate."

The newer engines like the Ecotec have greater resolution off of the flywheel. Why cant a timing wheel be developed for the older cars (30-2 etc.) that has greater resolution? I understand that is one of the reasons that the direct injection can be successful is the greater resolution/therefore more accurate timing. Cant a hall sensor/wheel be retrofitted to give this higher resolution, the computing power is surely available to take advantage of improved algorythms? Seems like some of the ECU's dont even use the cam timing sensor to make better calculations.

TheArchitect

>>The newer engines like the Ecotec have greater resolution off of the flywheel. Why cant a timing wheel be developed for the older cars (30-2 etc.) that has greater resolution? I understand that is one of the reasons that the direct injection can be successful is the greater resolution/therefore more accurate timing. Cant a hall sensor/wheel be retrofitted to give this higher resolution, the computing power is surely available to take advantage of improved algorythms? Seems like some of the ECU's dont even use the cam timing sensor to make better calculations.

Yes, higher tooth counts are potentially better, like I said, to make advantage of the higher tooth counts, you have to use every tooth.
This simply is not the case with many SEMs.

Most cars today use 60-2, Ive never seen 30-2, not that it wouldnt be a usable wheel, it wouldnt be as good of performance as compared to the 60-2 wheel.

Lots of people retrofit timing wheels to crank pulleys, lately we have come up with higher resolution wheels to go in distributors for a better than stock performance, but a bolt on solution that doesnt involve machining or welding to the crank pulley.

We support a huge number of timing wheels and oddball cam setups, we also support the 135 tooth Audi flywheel used on older Audis and Porsches, which uses a second sensor for crank synch and a third hall sensor for cam synch.

Running a non-missing tooth target off the crank has some significant disadvantages becuase it requires a rather high accuracy "pin" for the TDC reference, and like I said more sensors. If the TDC sensor fails, you have a definite no-run situation after the engine stops.

Basically if there is demand for a particular crank target, we support it.

We have support for the oddball hires subaru target, the 24 tooth GM target, even the new Chrysler Hemi which is about as strange as the come.

None of these targets are as accurate as the 60-2 though.

We support:
60-1 crank.
60-2 crank.
120-2-2 Cam.
120-2 Cam.
135 crank + TDC pin.
36-1-1 crank.
36-1 crank.
36-2 crank.
24X GM using Cam for synch.
60-2 GM with oddball Cam waveform.
Chrys. Hemi.
48-1 crank.
24-1 crank.
20-1 crank.
12-1 crank.
48-2 Cam "one sensor crank and cam synch".
24-1 Cam "one sensor crank and cam synch".

Other special purpose decoding methods we dont talk about.

And yes, we use every single tooth for realtime position decoding.


You want to stay away from using a hall sensor for for high tooth count wheels since the internal magnetic circuit is not instant responding like a VR sensors are. This can lead to an RPM dependent timing lag error due to the switching speed and slew of the hall effect output. This lag error changes with temperature and phase of the moon, so not something you want to just map out in the timing map.

A400

Thanks, I meant 60-2 like A4. Got the contact info w/send something soon - THANKS!