Fuel injected B3 wasted spark ignition project with schematics and lots of pictures.

[Festevil3]

Hi 'ya folks,

I'm going to be updating this thread with a simple solution to all the fabrication. This new system should be pretty easy to build.

I'll also post the dimension of all the brackets that are specific to Aspire/Festiva.

Stay tuned!

sub'd

This guy knows his stuff

[jason_]

http://www.yd-tech.com.tw/pdf/74LS/74LS125.pdf

http://www.fairchildsemi.com/ds/CD/CD4049UBC.pdf

I'm sure this will help the folks curious to understand what the two ICs are actually doing.

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro

[fujioko]

Thanks Jason for posting data file links!

Here we go!

This build is based on the information I already published and new info. I may need to add or change things as the build progresses.



I started with a printout of the schematic that is somewhere in this thread. I grabbed a Radioshack protoboard and a highlighter. I like to use the highlighter to color in the circuit as I build it. When I’m done everything should be highlighted.



About halfway through the circuit board build. At this point I was able to power up the circuit and double check the five volt regulator was working. I’m using chip sockets in order to make most of the circuit board serviceable on the side of the road.



Close up of the half done circuit board. I’m considering producing real circuit boards if this experiment is successful on the Festiva/Aspire. Right now my only I can only prove this system works on a hybrid B3 engine. The circuit board was finished shortly after the picture was taken.

NEXT....




This is an early model Miata CAS. 90-93 model year. Newer CAS used on 94 and up require a lot of fabrication to make them work. This one should be simple.
I paid $65.00 for this on ebay, however A week latter I spotted a Miata at the local Pick & Pull. Pick and Pull got $5.00 for the same part. I grabbed it so fast!



Open the CAS up and remove the rotor. The rotor needs to have one of the “windows” extended.


I used blue stain to highlight where I’ll be working. In a pinch you can use a sharpie to highlight.



I used a compass to draw in the extended radius



A small file eats up the metal fairly fast. This mod doesn’t need to be perfect because it has no effect on ignition timing. This window is used to switch what coil pack is enabled. The four smaller slots on the outside diameter are related to ignition timing. No modifications are necessary for those.



The finished rotor (for now). Once I get everything sorted out I may need to re-index the rotor for TDC position.

That's all for now!

Stay tuned!

[crazyrog17]

I'm excited! Good work man. I should come check it out firsthand sometime. Is the possibility of COPs getting more feasible?

[Zanzer]

Is the possibility of COPs getting more feasible?

X2

[jason_]

Thanks Jason for posting data file links!

Here we go!

I assumed posting the data files would help people understand the triggers and inputs and such. Hopefully give a visual perspective of what's taking place. In a nutshell it's the control over electrons.

[jason_]

Is the possibility of COPs getting more feasible?

X2

Good question!,

The major issue is COPs use a shorter dwell time and would burn out within a half hour or less.

The Festiva ECU generates a signal with a dwell time of approximately 5ms and COPs only need about 2ms. Most wasted spark coil packs are happy with a 5 ms dwell.

Megasquirt has adjustable dwell time so it can be programed to send the correct signal.

It is possible to slam the COP with a 5 ms signal but you need to do some math and add some high wattage resistors. The circuit has to be analyzed with AC rules. I don't know the resistors values off the top of my head but it is possible.... I think.

now, only if everyone had an oscilloscope @ their work bench.....

hmmmmmm

[fujioko]

Hi 'ya Jason,

yeah, an oscilloscope is very handy. I cant imagine doing this sort of development without one.

The wasted spark system I'm publishing works using a Saturn coilpack for economical reasons. I do have some Ford V8 COP units in stock and I'll do a COP version of this as well. The COP version will still be wasted spark.

I have a buddy who is going to be testing this system on his Aspire and will report any gains in fuel economy/ performance.
I'm thinking if the system shows some gains, it may be worth it to produce the circuitboards to eliminate the hand building of the circuit.

I should be mounting the coilpack today and start integrating the wiring. Stay tuned for more pictures.

Jim

[greywolf200]

This and you is absolutely amazing and too cool. Keep up the good work...:thumbs_up: