Dick Nyquist wrote:
>
> someone asked about an ignition system that gets rid of the distributor.
> (for a SAAB/TR7 engine swap).
>
> Many new General motors cars use a crank fire system that has no distributor.
> Similar but more expensive and sophisticated systems are also used on may
> circle track race cars.
**** A few years ago, I did a project with Motorola's 68332 CPU chip.
This was created specifically for automotive purposes, and there was a
distributorless ignition system described in the app notes. It didn't
seem like any big deal. Mainly, there were to spark coils, each with
two HV outputs. You fire this one *NOW*, it catches, say, cyl #1 at
the top of the compression stroke. The other output fires too, in
cyl #4, which is also at TDC, but on the *exhaust* stroke. So that
spark is ignored, there's nothing to burn in the cylinder, right?
The `332 was an interesting chip. Besides the CPU guts, it had
16 general-purpose timers. Good for things like... timing sparks!
Scuttlebutt was that Moto had designed it for GM. GM had asked Moto
to sell the chip to nobody but GM, Moto told them to go to ****.
My old `76 Kawasaki KH400 had a crank-fire system. There were three
sensors around the end of the crank, going to three coils. One day
I decided to go out and tune the thing. I set up the timing light,
started the engine......... and thought I was hallucinating. You know
how timing marks always dance around when you strobe them? Well,
these just stayed put. I mean, the didn't move at all, not even a
millimeter. I revved the engine up to 8K or so.... Maybe the mark
moved a teensy little bit, maybe not.
Kawasaki had a simple system, there was no advance. Advance is where
you start to need timers and CPUs.
- Jerry Kaidor
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