Wiring wasted spark on a odd fire V10 (s100)

Discuss which Sensors work best with these ECUs and share how you are using inputs and outputs
Alex DTA
Posts: 1622
Joined: Fri Feb 28, 2014 1:03 pm
ECU Model: S40 Pro
Distributor: DTA
Firmware Version: 79

Re: Wiring wasted spark on a odd fire V10 (s100)

Post by Alex DTA »

The main problem with this engine isn't the odd fire, it's the crank trigger. Here's a picture:
Dodge Viper V10 crank trigger.jpg
That only has 10 teeth, the S Series require 12 at a minimum. These are also unevenly spaced.
A V10 also requires the number of teeth to be divisible by 10, so the only valid numbers are 20, 30 40, 50, 60, 70 and 80.
The odd fire also requires a cam sensor.

The wasted spark coil packs shouldn't be a problem. Wiring them up as per OEM will result in the same firing pattern and timings as OEM.

We have a customer who has fitted an external 60-2 trigger wheel, and the engine runs. I'm not sure how much further they've got yet. It's running the standard wasted spark coil packs.
Rob Stevens
Posts: 1247
Joined: Thu Jul 28, 2011 4:10 am
ECU Model: S100 Pro
Distributor: None-Coil On Plug :)

Re: Wiring wasted spark on a odd fire V10 (s100)

Post by Rob Stevens »

It looks like that flywheel could be adapted to have 20 equal teeth.
But the OP wants to use the existing wasted spark coils but the matching wasted spark would not be required at the conventional 180 degrees away. I thought that perhaps you could wire 2 outputs to one duel coil, fine in principal but its more than likely that the dwell requirements would scupper that idea?
Alex DTA
Posts: 1622
Joined: Fri Feb 28, 2014 1:03 pm
ECU Model: S40 Pro
Distributor: DTA
Firmware Version: 79

Re: Wiring wasted spark on a odd fire V10 (s100)

Post by Alex DTA »

Two unamplified coils to one output is very unlikely to work, and is risking blowing the driver.
Rob Stevens
Posts: 1247
Joined: Thu Jul 28, 2011 4:10 am
ECU Model: S100 Pro
Distributor: None-Coil On Plug :)

Re: Wiring wasted spark on a odd fire V10 (s100)

Post by Rob Stevens »

:0 I wouldn't actually try it without asking you to test it first! Just thinking how the OP could make it work like Dodge did, they must have connected 2 outputs to 1 coil?
Alex DTA
Posts: 1622
Joined: Fri Feb 28, 2014 1:03 pm
ECU Model: S40 Pro
Distributor: DTA
Firmware Version: 79

Re: Wiring wasted spark on a odd fire V10 (s100)

Post by Alex DTA »

Where's your sense of adventure? :)
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: Wiring wasted spark on a odd fire V10 (s100)

Post by stevieturbo »

I've never had any luck trying to get more than one inductive coil to fire off a single trigger ( unless wired in series )

As for the trigger pattern....At present it cannot work as is....but is that a hardware limitation, or could the trigger not be added to the software/firmware ?
Alex DTA
Posts: 1622
Joined: Fri Feb 28, 2014 1:03 pm
ECU Model: S40 Pro
Distributor: DTA
Firmware Version: 79

Re: Wiring wasted spark on a odd fire V10 (s100)

Post by Alex DTA »

stevieturbo wrote:As for the trigger pattern....At present it cannot work as is....but is that a hardware limitation, or could the trigger not be added to the software/firmware ?
Apparently it's a hardware limitation. But that would also read as 20(Not checked properly, could be something else)-2-2-2-2-2 due to the uneven angles. Or something like that.
Something to add to the to do list.

If anyone ever has the chance to generate a crank scope on one of these, pass it on and I'll see what I can do.
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: Wiring wasted spark on a odd fire V10 (s100)

Post by stevieturbo »

http://www.vems.hu/wiki/index.php?page= ... iperEngine

http://www.msextra.com/forums/viewtopic ... 31&t=40650

http://www.vemssupport.com/forum/index.php?topic=1972.0

I've often wondered why an ecu couldnt simply learn a crank trigger.

eg leave cyl1 plug in, all others removed and spin the engine over.

The ecu would see the repetitive pattern, it would also see a speed change when cyl1 is on compression and should be able to work everything out from there and just learn the pattern ?

None do this...but it sounds easy lol.
User avatar
ignitionautosport
Posts: 577
Joined: Wed Jul 27, 2011 5:30 am
ECU Model: S80 Pro
Location: New Zealand
Contact:

Re: Wiring wasted spark on a odd fire V10 (s100)

Post by ignitionautosport »

Rob Stevens wrote:2 outputs to 1 coil?
I think you all misread that.
| '94 GSR Lancer | '96 Toyota Carib 20V | '83 Toyota Starlet | www.ignitionautosport.co.nz |
Alex DTA
Posts: 1622
Joined: Fri Feb 28, 2014 1:03 pm
ECU Model: S40 Pro
Distributor: DTA
Firmware Version: 79

Re: Wiring wasted spark on a odd fire V10 (s100)

Post by Alex DTA »

Yes, we did! :lol:
You would need to use diodes to protect the output that is off while the other one is firing.
Post Reply