Direction

[The_Mechanic]

A digression providing food for thought:

I'd like to suggest one thing regarding timing position sensors:

On all engines, it is far more accurate to obtain timing information 
(via toothed wheel, hall effect sensor/magnets, etc.) at the crankshaft, 
rather than at the distributor or camshaft.  Of course, this is not always 
feasible, but in general, much greater timing accuracies can be achieved. 
This is especially true if the given crank has been indexed so
that each rod journal's relative position is known accurately.  This is 
typicial of a blueprinted race engine, or for someone looking to extract 
the "maximum" performance (ie, precision, accuracy) of their EFI system.  
That *IS* the ultimate goal here, isn't it? Make _serious_ (but 
managable) horsepower? It sure is mine... 

In any case, the timing position sensor type needs to be determined.  I'm 
told that this piece is the "weak link" in the Electromotive TEC-II 
system.  What do people think is the best way to go here?  The TEC-II 
uses a 60 tooth wheel and sensor to read crank postion. (a 120 tooth 
wheel is available for distributor installations) Other crank triggered 
ignition systems use magnets imbedded in the front pulley or harmonic 
balancer.  Others use optical triggers.  What say?  Anyone out there have 
any practical experience? Do tell...

Erik
The University of Texas, Austin  

1968 BMW 2002. Currently using sputtering Weber DCOE's.