| Getting back to this crank trigger tooth count and timing error/resolution thing... Previous post I've done more research and found my original assumed RPM acceleration rates were way over-estimated. I talked with a NHRA Pro-Stock (1500 HP NA V8 engines) tuner and they were willing to offer that they routinely measure peaks of ~1300RPM/sec acceleration in 1st gear and ~600RPM/sec acceleration in high gear (1:1) on mid-6 second 1/4 mile runs. This is near constant-rate acceleration because the engine is under load. The acceleration rate changes that can theoretically cause a timing error must only occur between two adjacent crank teeth, and while I admit acceleration changes are possible, near-instantaneous large changes in acceleration between two adjacent crank teeth on an engine under load are not worth worrying about. Obviously our VGs are not going to be accelerating faster than this... unless we are talking about free-revving and I'm not going to place any value on timing errors detrimentally impacting an engine being free-revved. Below is a revised graph from the previous post (see link above) showing the potential timing errors at 3000RPM with 4 through 60 tooth crank trigger wheels and RPM acceleration rates of 250 to 1500 RPM/sec: 
From the graph, we can see at 3000RPM, the max error for a 12 tooth crank trigger wheel is 0.75° at a max acceleration of 1500RPM/sec Regarding ECUs and trigger tooth count compatibility:
AEM
I found that the lower-end units (V1, V2, EMS-4) are only capable of processing a 12 tooth crank wheel but all AEM units (even the V1) can physically use a crank trigger wheel with up to 60 teeth (must be divisible by 12) because their software allows the user to program it to ignore the extra teeth (see "Crank Tooth Control" in AEM software). Haltech Platinum Pro Plug-in
The Platinum Pro Plug-in software has only two options: stock Nissan CAS trigger pattern, or 24 + 1 (cam driven AEM-like disc). The 24 + 1 can also be applied to a 12 tooth crank mounted wheel, but no other physical tooth count is applicable for this platform. Haltech Elite
The Haltech Elite software can be configured to work with most common trigger tooth counts. Brand XYZ
If you run a non-AEM/Haltech ECU on your Z32, please comment if you know of its compatibility or limitations with a crank trigger.
So... What I am getting at is: in order to accommodate the Haltech Platimum Plug-in ECU users I will only be offering a 12 tooth trigger wheel with my upcoming crank trigger kit. I hope I've offered enough information to explain timing errors and dispel some of the misconceptions about theoretical resolution benefits of higher tooth count wheels.
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Crank trigger teeth and ECUs... - 
