In article ,
The Natural Philosopher wrote:
I ask again. Name one new car with any form of distributor. If one
exists, avoid it. As it has an ancient engine design best left for the
science museum.

All of them. Without a distributor you need at least one coil per
sparkplug, unless you want to take the risk of firing all the plugs all
the time and the possibility of a misfire ..

Never heard of wasted spark? One coil for a pair of cylinders and only the
crank position needed.

Additionally you need to tell te EFI and ignition system which part of e
4 stroke cycle you are ion to time the sparks and injectors correctly.
This means a divide-by-tow rotor and a sensor of some sort..since
camshaft is already needed to control the valves, is normal to tack the
distributor onto that and use it to do the two things it still needs to
do - distribute the spark to the right plug
and
- provide timing information for the injectors and the ignition.

Err, going back to the days of injection and dizzies, injection was
indirect, and injectors fired as a batch. Not sequential. And just when
they opened not particularly critical - just the time they were open for.

So a modern distributor does less, - its doesn't have a mechanical spark
generator in it and it doesn't have centrifugal advance/retard and
vacuum advance on it - that's all done electronically, but it still
shuffles the spark around and provides a convenient place to put a
camshaft sensor.

Why would you go to the effort of providing an accurate map via
electronics but use a trigger which is all over the place - jitter from a
cam drive and belts or chains which stretch?

Look in most petrol cars today, with an OHC and you will see a 5 wire
lump 4 a 4cyl engine) stuck on the end of the camshaft, and probably a
sixth small wire there as well that's the sensor. four wires go top the
lugs, and the fifth goes to a coil or coil pack, which is usually bolted
somewhere else

Really? I keep on asking - what make is this? What you're describing was
on a Maestro...

even if the car has one coil per plug, it STILL needs a way to selct
those..and the camshaft sensor is still needed.

Wasted spark. Again. But given how common variable valve timing is, a cam
position sensor is common too. So that gives the cylinder which is firing.


That's as little of the distributor as you can get away with. Arguably
at some point its not a distributor any more - but that is when it stops
distributing the sparks and that means an expensive multi-coil ingnition
system that is not found much on cheaper cars.

Are they still making Lada?

--
*Forget about World Peace...Visualize using your turn signal.

Dave Plowman London SW
To e-mail, change noise into sound.