[boostedbrick]

I am doing a Baleno g16b dizzy swap into a sierra at the moment, and as a way around swapping out the cam to a vit unit i'm going to electronic ignition with separate coils. The coils will be fired off an output from a modified dizzy with timing adjustment much the same as a normal dizzy. As im using VT commodore coils, I have to fire two cylinders at once....

With the firing order been 1342 I presumed the injectors would also fire as such. But looking at the wiring, injectors on cyl 1/2 fire off one signal and injectors on cyl 3/4 fire off the other signal. If cyl 1 is on its intake stroke what would cyl 2 be doing? I need to know which cylinder I can waste spark on since the coil will fire two at once... If that makes sense

[royce]

1 plus 4 go together 2 plus 3 go together

when the cylinder on compression fires, the other is at the top of exhaust

Back then they didnt have real multipoint injection

Look at G13BB Coils, will be a lot neater than commodore coils, think about using its cam sensor too

How are you going to work the timing and dwell on the coils?

[boostedbrick]

If 1/4 then 2/3 go together that should work well.

My brother is designing/building it but ill answer what i can. As far as we can tell, I should be able to adjust the dizzy/sensors inside to get timing in the correct spot. The dizzy will still adjust the same as standard, and the plate the sensors are mounted too inside the dizzy will be slotted and adjustable.

Dwell will be controlled by the ignition circuit, will have a rotary switch to adjust as necessary.

There is enough room in there to keep the standard cam sensor as well. Ill have to look at a g13bb unit as and option though.

[JrZook]

So you are going to use an old school centrifugal and vacuum advance dizzy on this to control timing?

[fordem]

boostedbrick wrote:

With the firing order been 1342 I presumed the injectors would also fire as such. But looking at the wiring, injectors on cyl 1/2 fire off one signal and injectors on cyl 3/4 fire off the other signal. If cyl 1 is on its intake stroke what would cyl 2 be doing? I need to know which cylinder I can waste spark on since the coil will fire two at once... If that makes sense

With a 1342 firing order when #1 is on the intake stroke, #2 will be on the compression stroke.

Here's the sequence ....

1-IN 2-CO 3-EX 4-PO
1-CO 2-PO 3-IN 4-EX
1-PO 2-EX 3-CO 4-IN
1-EX 2-IN 3-PO 4-CO

There will be occasions on which the injector is spraying fuel at the back of a closed intake valve - this is not as much of a problem as it would first appear - once the engine is running the fuel mist will still be hanging in the air when the valve opens and the piston starts down on it's intake stroke. It can be a problem when the engine is started, so most EFI systems simply batch fire all the injectors whilst cranking.

There are engines (the Swift GTi for example) that batch fire all four injectors and others that fire the injectors sequentially (sequential fire) at low rpm and switch to batch fire as the revs increase.

[boostedbrick]

JrZook wrote:

So you are going to use an old school centrifugal and vacuum advance dizzy on this to control timing?

No vacuum advance on this model Baleno. Possibly on a later model.



Cheers fordem, that explains it better. I had just always assumed without looking at it one would fire at a time.

[JrZook]

boostedbrick wrote:

JrZook wrote:

So you are going to use an old school centrifugal and vacuum advance dizzy on this to control timing?

No vacuum advance on this model Baleno. Possibly on a later model.

Mmmmm I'm sure the dizzy does nothing other than distribute the spark in these and provides a pickup signal for the ECU. All ignition timing is controlled by the ECU.

[want33s]

Seems a bloody lot of head scratching when all the Vit angle drive parts are available to convert it.

[boostedbrick]

JrZook, i can understand how that would work on a coil model but how would it do it on a dizzy motor?


Want33s, comes down to cost. Parts and labour would be allot more. I should be able to do this for under $100....

[royce]

On my vit (more or less same thing, coil in cap type) the ecu takes care of timing and dwell changes, even tells me what it is on my cool laptop readout

the dissy does nothing but tell the ecu the engine speed and cylinder location based on the pules from teh pickup, its sent to the ECU that sends the signal for the coil back

You should look at the Ford EDIS module and the megajolt system, its a proven way to get what you want, but I still dont see the point compared to converting it to angle drive (assuming you can, what dissy does the baleno run?)

[boostedbrick]

Ok,i had a chat with my brother about it. He reckons we can use the signal from the ecu to fire the coil and controll dwell. The ignition circuit is already built todo this. The sensors in place in the dizzy will just act to prime the secific coil that needs to fire next.


The dizzy has a seperate coil. Changing to angle drive requires a cam, dizzy and angle adapter swap.

All im trying todo is keep costs down going this route.

[royce]

Can you explain how you are going to take a signal that is designed to fire a single coil and split it to fire 2 coils, in the correct order sequence?

I am interested as ive never really heard of anyone doing this before

[JrZook]

You will need another pickup in the dizzy to work out weather to fire coil set 1 or 2. Two 90* sections to trigger a hall effect with Schmidt trigger or optical sensor running off the dizzy shaft will give you enough phase info the select the coil set to be driven

[Damo]

royce wrote:

On my vit (more or less same thing, coil in cap type) the ecu takes care of timing and dwell changes, even tells me what it is on my cool laptop readout

Does that give you a timing map by any chance? I wonder if you could extrapolate a table from captured data?

[boostedbrick]

The dizzy still has its standard hall effect sensor speaking to the ECU. There will be a further four sensors fitted, 1 for each cylinder, which originally were there to fire the coils for the correct cylinder.

Now that we will be using the ECU to fire the two coils, the four sensors will tell the ignition circuit which coil it needs to fire. Every time it passes a sensor it will activate the correct coil that is coming up in the sequence.

[JrZook]

Only need one extra sensor and 2 pickup areas which will simplify the lot! If the sensor is in the pickup areas then it's coil 1 if not its coil 2.

Can't really see by your pic but it seems like an LM7805 regulator you are using. Better to go to a more robust auto spec LM2940 reg

[Rhinoman]

The Baleno dizzy that I am used to has a five tooth sensor with the fifth tooth indicating which cylinder is no 1. There is no need for any additional sensors, just some extra maths in the ignition software, if you run a wasted spark system. If you intend using another system then you will probably need to grind off the fifth tooth.

[boostedbrick]

My brother looked at that but I don't think the signal was clean enough for what he wanted...

Motors going in this week so i should get to try it out next weekend and see how it works.

[dougies_tx5turbo]

this is alot of head scratching for me. hope it works so you can take me out for a spin, so i can feel the extra grunt.

[boostedbrick]

dougies_tx5turbo wrote:

this is alot of head scratching for me. hope it works so you can take me out for a spin, so i can feel the extra grunt.

Should be ready soon





Control circuit needs to be finished, just had to wait till the motor was in the test some things. But as it is now, if the computer didn't want to control things it would run.. Will get cracking on it tomorrow and see if we have any luck.

[boostedbrick]

Well that turned out to be a big waste of time and money... I took measurements off my softtop, which it turns out has an extra 25mm+ of space to the firewell... Doesn't fit into the tin top though, even with the firewall bashed...

Good idea, poor execution