555 EFI

[Clarence L.Snyder]

Chris Conlon wrote:
> 
> This sounded like fun so I decided to play with it some, at least on
> paper. I have a question, though. What's the range of adjustment due
> to CTS, and what does that adjustment look like? I'm thinking that
> at "warm" temp or above, there is no adjustment, and below that temp,
> the pulse width gets multiplied by some value. The colder the temp,
> the larger the value. What would that max value be, though? 1.1?
> 1.5? 2.0?  In other words, how much of a % difference does coolant
> temp make in the pulse width? I'm thinking it's 50-100%, which means
> I have to put it at a different place in my circuit.
> 
> >Okay, who's gonna be the first one to say it would be easiear to skip all
> >the op-amps and use a PIC and some code?  ;)
> 
> Hah! You beat me to it. This is more fun though. ;)
> 
> Also a nod to whoever pointed out that this is "just" D-Jetronic, I
> was thinking exactly that myself. ;)
> 
> Anyway I'll try to get the circuit drawing into some format that
> other people might be able to look at.
> 
>    Chris C.
Stoich is 14.7:1? Cold enrichment can be as much as something like 8:1
or 6:1 from what I have been able to find - which is not much.

What pulse width difference are you looking at for MAP?
I figured about 50Ms for full power (1.5")at 4800 RPM, +/-and about .025
for idle 15" vacuum- this for a 4 cyl with batch fired X2 setup. Cold
enrich at idle could be as high as .050.

Interested in seeing your doodling.