analog EFI

[David Doddek]

The MSD ignitions that are multi spark have a open collector tach output.
Just use that to run the EFI unit.


>In message <0ECX7NG8T00FZ7 at kauri.lincoln.ac.nz>, Simon Quested
><questeds at whio.lincoln.ac.nz> writes
>>Hi All
>>
>>I have a '73 Ford Capri with a 2L 4 cyl engine I also have an analog 
>>EFI system that I am about to put in. It uses a map sensor and a 
>>pickup from the -ve of the coil to control only the fuel. It has 6 
>>pots that set the on time for the injectors over the rev range.  
>>
>>I want to put a MSD ignition module in but I think that this will cause
the efi 
>>ecm to freak out?
>>
>>Am I right in thinking this?
>>
>>Thanks
>>
>>Simon
>>+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>  Simon Quested (E-mail questeds at lincoln.ac.nz)
>>  Computer Technician, Silicon Graphics & Windows NT Support
>>  Centre for Computing and Biometrics
>>  LINCOLN UNIVERSITY OF NEW ZEALAND
>>  Phone (64)(03) 3252811 Ext. 8087
>>+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>http://www.lincoln.ac.nz/ccb/techs/simon/default.htm
>>+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>If voting could really change things, it would be illegal. 
>>+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>It may not.  I'm not sure which of the MSD units do the "multiple spark
>discharge" thing to the coil.  I don't think they all do.  If it is a
>multiple discharge type then it probably will screw up the trigger
>signal to the efi unit.  It may depend on the time constant of the input
>filter in the unit.
>Is it not possible to trigger the EFI unit from the MSD ignition
>trigger?  I don't know if this is a Hall effect trigger or the variable
>reluctance type, but it will give you one pulse per cylinder.  It's a
>pity that the MSD module doesn't put out a trigger-output pulse for the
>synchronisation of external EFI units.  (It might do that of course,
>perhaps someone else might know)
>
>bye,
>-- 
>Chris Morriss
>
>
David Doddek     pantera at pobox.com    www.pobox.com/~pantera    217-422-3722
69 EFI Fairlane, 89 T-bird SC, 74 Twin turbo NOS EFI Pantera #6825
If you are going to go fast, go real fast.