Electronic Distributor Adapter

[Shel-Game]

You know, it MIGHT be possible to do option #1 and #2 using a completely stock SMEC.

You'd have to re-program it to interpret the Crank/Cam sensors from the "old" 2.0/2.4 - not easy but not insurmountable; and you'd have to figure out how to drive the "other" coil. It just so happens that the V6 SMEC has an extra driver, and a pair of internal control lines (since there was no room on the 14-way for them). So long as the driver for the 3rd pair of injectors can handle driving an ignition coil instead, it should be no problem...

You'd also have to re-program one of the other solenoids to be for the wastegate, since the 3rd injector driver uses the same output as the WG solenoid on the turbo SMECs. You'd have to lose either EGR, Purge, or cruise to make it work. Most people don't have EGR anyway...

[90TurboVan]

No clocking, it generates the signals the computer uses to generate the tach signal.

I did think of reprogramming the SMEC/SBEC and adding another driver (there is some I/O left on the expansion chip, right?). An injector driver wouldn't have the voltage rating to drive a coil, but maybe you could replace the transistor with a higher rated one? You know the SMEC code/hardware better than I do, Shel-Game. Anyone come up with a schematic for the SMEC yet?

Also, the SBEC has no where near the code and hardware documentation that the SMEC/LM/PM has, so I'll end up using one of these adapters no matter what.

[90TurboVan]

So, here are all the different diagrams, as I have found with an oscilloscope on:

1987 T1 Daytona



Numbers are at base advance.

2001 PT Cruiser (Non-NGC)



Top is crank, bottom cam. Numbers are at 9 degrees BTDC.

2003 SRT-4 (NGC)



Top is cam, second is crank, third is gray HEP, fourth is black HEP. Numbers are at true TDC.

Just so they're all in the same place.

[Shel-Game]

Quote:

Originally Posted by 90TurboVan So, here are all the different diagrams, as I have found with an oscilloscope on:

Any chance you have this data for the '91 T3? I wonder if it's the same/similar to the early 2.0/2.4?

[TurboGLH]

Quote:

Originally Posted by Shel-Game Any chance you have this data for the '91 T3? I wonder if it's the same/similar to the early 2.0/2.4?

From my understanding it's not.

[Shel-Game]

Quote:

Originally Posted by TurboGLH From my understanding it's not.

Oh well - I'd still like to see that as well...

[90TurboVan]

I don't have any access to a T3 car, and they already have DIS and sequential injection, right? If someone has disassembled a T3 SBEC, maybe you could deduce the sensor outputs from that?

[Shel-Game]

Quote:

Originally Posted by 90TurboVan I don't have any access to a T3 car, and they already have DIS and sequential injection, right? If someone has disassembled a T3 SBEC, maybe you could deduce the sensor outputs from that?

I've dis-assembled the T3 fairly thoroughly at this point. I just wanted to compare the timing chart to the code to try and figure out what all it's doing and why. That way, I could try and build a new routine to decode the 2.0/2.4 timing signals for a standard SMEC or SBEC...

[Wizard]

This current link is this latest version or is there other link to download the info and stuff?

How's the progress on NGC adapter?

On the driver side for the DIS pack, does not look like it is current limited design. Supposed to have this to prevent drivers or the coil from burning out.
Set up circuit to 4A per drivers max or make this much simpler, use:

VB921 drivers or two 4 pin HEI modules on their heatsinks.

Make sure the programming turns off drivers if the input signal stops longer than certain milliseconds, around 200 millisecond or less.

Regulator 5V always MUST have four capacitors, bypass cap (poly is best around 100nF 50V for high freq noise and 100uF or larger for bulk filtering on input and output. Good idea to have inductor for noise blocking on the supply. The coil drivers should own HEAVY ground plane to a thick ground wire.

Cheers, Wizard

[90TurboVan]

Current link is the not the latest of the hybrid type adapter. I'm waiting to see how some changes I've made work out before I put up all three versions. I know that design is not current limited, I can't find VB921's anywhere from any of the electronics distributors, and ST apparently doesn't make it anymore. I also can't seem to find any other IC's like it ie. current limiting coil drivers. I don't like using two more modules in conjuntion with the adapter, and the HEI modules control dwell and have a VR input. The drivers are short circuit protected. If the input remains on for longer than 1 second, all outputs go off and the mcu goes into and infinite loop. A second is more than short enough to prevent burning anything up. Any suggestions on how to make the circuit better are always welcome.

I would gladly use the VB921's if anyone knows where I can get the surface mount one or even the standard 3 pin one. The Microsquirts use it, so I guess B&G have to be getting them somewhere.

There is a 100nf filter capacitor across the PIC that also serves to filter the regulator. I've never heard anything against ceramic, and that's all I ever see used on professional boards. The larger cap value really isn't critical. 22uf is what I had in smt and it filtered the output just fine as far as I could tell. There is a noise suppressor capacitor used on the + side of the coil which is where the circuit should get its power, I assumed this would be sufficient on the input side. Am I forgetting a capacitor, you said four but only described three. An inductor would also be a good idea.

NGC adapter is coded and not tested, and I'm working on the non-NGC code.

[TurboGLH]

VB921 Ignition Coil Driver DIYAutoTune.com
vb921 current availability from distributor 1-Source Electronic Components

[turbo.shaft]

Quote:

Originally Posted by TurboGLH VB921 Ignition Coil Driver DIYAutoTune.com vb921 current availability from distributor 1-Source Electronic Components

$5.50 is cheap insurance to avoid a $100 tow.

[90TurboVan]

I don't know about 1Source, never heard of it. I didn't want to get a whole bunch from DIY cause they aren't a real distributor, but I guess I'll try.

[Aries_Turbo]

this is pretty cool. -subscribed-

[jonnymopar]

Quote:

Originally Posted by Aries_Turbo this is pretty cool. -subscribed-

Absolutely! There's no way it will be done in time for me, but when the car is off the road for the winter, any help you guys need, please let me know. I've got a SMEC car with a pre-2003 2.4L in it that I certainly wouldn't mind offering up for testing.