JasonC SBB

The AEM can use a higher resolution 12 tooth crank trigger wheel.

How about the MS, Hydra, and Adaptronic?

y8s

iTrader: (8)

Adaptronic can do it. it has a table where you just fill out the locations of the teeth.

Hydra I'm not sure.

Joe Perez

iTrader: (8)

The Megasquirts (1, 2, and 3) can be set to read pretty much any wheel pattern imaginable, with any number of primary teeth and any number of missing teeth, with the following caveats:

1: The missing teeth (if more than one) must be sequential.

2: The spacing of the teeth must be even (there are some custom exceptions possible with the MS2/3, but that is rocket science.)

3: A second (cam) wheel is supported for use with crankwheels that have no missing teeth, and/or for fully sequential operation. This wheel is not required for batch-fire when a missing-tooth crankwheel is used. The camwheel can be used whether or not the crankwheel has missing teeth.


With the MS2 and 3, higher toothcounts equal better spark accuracy, as the ECU will, in realtime, select the tooth which is closest to (but prior to) the calculated spark angle, and use that tooth as the trigger to launch the spark countdown timer. On the MS1, this feature does not exist. You can use any toothcount wheel that you wish, however you must specify a particular pair of teeth to be the trigger teeth, and these teeth must be far enough prior to TDC (and BDC) to accommodate the greatest possible spark advance. IOW, it is functionally equivalent to having a two-tooth wheel, with a phantom third tooth (the missing tooth) used for phasing. One exception does exist, in that during cranking, even the MS1 is capable of triggering on a specific, predefined tooth, as opposed to calculating all the way back from the "primary" trigger tooth.


A question: I understand that with the default configuration, the AEM is limited to a 12 tooth wheel. However I have come across some postings on various forii which suggest that it is possible to use more conventional wheel designs (such as 36-1) by setting up "tooth control table" which I don't quite understand. Examples:

36-1 teeth on the crank , 1 tooth on CAM

http://www.et.byu.edu/groups/icengin...ecognition.pdf

Reverant

iTrader: (10)

MS2 can't go any higher than 60-2 because the sheer amount of interrupts per second cause the available mainloop time to decrease to dramatic levels. Simply put, there is not enough processing power in the MS2 to read a higher wheel than a 60-2. (From the top of my head, someone was trying to make it work with the starter teeth from a flywheel, IIRC 120 teeth.)

Jim

Joe Perez

iTrader: (8)

Well, that's probably true. I suppose that by "any wheel pattern imaginable" I meant to say any pattern that one might reasonably expect to come across in either an OEM or a common aftermarket application.

The 36-1 wheel, for instance, was a standard part of damn near everything Ford made for most of the 1990s, and as a result, is a de-facto standard in the aftermarket as well. Likewise, the 60-2 pattern was a common Bosch standard, and widely used by European OEMs around the same time period. There have been many other diabolically odd wheel patterns used by OEMs over the years, but I can't think of any which have a higher toothcount.

Joe Perez

iTrader: (8)

I've deleted a few posts and locked this thread for the moment at the request of the individuals who are doing the actual research on this concept. Please forgive me if this seems harsh, but I wish to respect their propriety until they choose to make a public announcement.