KISS Fuel Injection via PIC. Any interest?

[Darryl Snover]

Hi Simon,

I am interested in the PIC efi.  That, in fact, has been the angle that i
have been looking at to enhance my CIS-E injected Porsche 931.  I would
probably add input from an O2 sensor, just for a handy way of getting
tuning 'roughed' in and blah, blah, blah.

Best Regards,

Darryl Snover



>Hello all,
>with all this sudden interest in PICs, I am wondering if anyone else
>would be interested in a KISS (Keep It Simple Stupid) EFI based on a
>16C73 PIC ?  I am planning to do one for my 74 MGB.  The 'design
>guidelines' would be:
>
>- To replace SU HS4/HIF4 carbs, which are pretty minimalist pieces of
>equipment.
>- Batch fired injectors.  Software would work for any number of cyls.
>- Inputs would be TPS, Coolant temp, MAF or MAP, Air Temp ? and RPM
>signal picked off distributor.
>- Injector pulse width would be based on maps stored in EEPROM.
>Possibly using byte-wide EPROM + some interface 'glue' chips to enable
>the PIC to access 'external memory', which normally doesn't do.  If
>processing time allows a serial EEPROM would make interfacing dead
>simple.
>- The chip includes a serial port to provide a handy 'user' interface.
>
>This should be quite a simple system hardware wise.  It could be
>prototyped on a SIMSTICK type board, ($6 from Wirz electronics).
>The batch fire method removes the need for special pick-up wheels and
>sensors; there is no need for synchronisation.
>Use Sandy's very nice injector driver board for low impedance
>injectors.  High impedance types would be simpler.
>
>It should provide at least as good a performance as any analogue system
>without any greater hardware complexity.
>
>Potential points against such a system are:
>- Developing the fuel maps may be a problem, at least for the first
>person to try it for a particular engine :-)
>- You may still need some sort of I/O board to condition the input
>signals.
>- Would it really be that much simpler and/or cheaper than the EFI332
>system? and would it divert resources away from the EFI332 project when
>it really needs all the help it can get?
>
>Looking for feedback,
>Simon
>
>--
>------------------------
>Simon Bosworth
>simonb at primenet.com