8051 EFI

[Paul Corner]

Hi Mike

My toy is based around a Renault Alpine 1400cc cross flow - originally fitted
with some horrible down draught carb. Ran it for a couple of years with a pair
of Webber DCOE's. Then some 'erb told me that fuel injecting that lump was
immpossible period. 
So I rigged up some throttle flaps, one for each cylinder, and breadboarded a
simple control based on the SSI 67F687. It ran, eventually. But since the chip
never made it to the market, it was time to have a rethink.

Picked up a 4 wire Lambda sensor today - so once I've added a boss to the
exhaust pipe, I can play around with a closed loop control. More questions -
differential input buffer, input impedance, low pass filter, cut off
frequency...  I suppose suck it and see.
Wonder how far down stream I need to mount the sensor on a 4-into-1 exahuast....

As far as the software goes, most of the problems I have can be put down to the
fuel map - at the moment, a best guess data. With a lambda sensor, I hope to
have a self teach mode. Communication with a laptop is one area that needs to
be sorted. Then I can have a go at the ignition system - some bright spark
will tell me it can't be done. 

So there you have it, four sequential injectors and two coils on a 100x160mm
board.
Still interested ?

Regards, Paul.

> Very intersting!  Yes, I am always interested in what somebody can think of, 
> and get to function; and, no (probably) not interested in getting one (yet), 
> but I'm not even sure . . .
> 
> [Those aren't puns - I _hate_ puns!]
> 
> When I subscribed to the '332 list, I was just a bit too late into the '332 
> project, and by the time I had thought it over, the group buy was closed.  
> Is yours oriented to a four-cylinder engine?  I really need to do some 
> planning on the whole EFI matter!  I drive a carb'd vehicle - with an 
> integral intake manifold! - so hacking an ECM on my 'daily driver' is out.  
> My 'big project' engine is not even in hardware yet (design only).  Maybe I 
> do want to scratch-build my own;  wouldn't be 'better' than any other, but 
> it would be optimised for my application (yeah, right, buddy), and I would 
> know the 'why' of every little detail.  Some of us have a drive to do that! 
> (you know)
> 
> On the software, no major snag, I hope?
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