Help with building your Speeduino, installing it, getting it to run etc.
By kettlekev
I am looking at a distributor upgrade for a Vtec.

This is an upgrade that includes a new sensor package and a single igniter. This is normally used with the Honda ECU's.

The challenge I see using it with Speeduino is that while it generates a cam and crank signal, as it has a single igniter, I think the way it needs to work is the 4 IGN outputs from Speeduino would need to be combined onto a single line to drive the one igniter igniter. The upgrade then allows that igniter to be routed to each COP.

Speeduini uses TC4424 MOSFET driver chips and I'm not sure if the outputs can just be paralleled or need some sort of diode isolation?

Has anyone looked at these?
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I'm not seeing the benefit. I guess I'm missing something, but you want to take a 4-channel ignition setup, combine it to one signal, to split it into 4 again? :?
By JHolland
Are you running distributor mode? it seems like a better, and much cheaper, option would be to change the trigger in the distributor to allow you to run COPs. One ignition output being fed to multiple coils seems like a return to 80s setups like the original MX5/Miata.
By kettlekev
I'm probably not explaining this well.

The snake mod to the distributor in the link in the first post appears to show a new cam/crank sensor package and a new single channel igniter.

This was made to fit Honda ECU's where the dual wheel cam/crank signal gets fed to the ECU from the distributor then a spark table gets sent back through a single igniter a single distributor coil and to the plug cap/rotor/leads. At least this is how I think it works.

What I am trying to do is make the snake distributor mod work with Speedy.

Speedy give 4 separate ignition outputs but as far as I can see the honda ECU only gives one combined output to feed the original single coil.

I want to use the snake distributor with its new cam/crank sensors and its single igniter to drive a COP system but as far as I can see I then need to get all of speedys ignition lines combined into one to feed the single igniter and the modified snake distributor cap.
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Yeah, that should do it, as a distributor output (single coil). But, if Speeduino is getting the wheel info, why not directly control the 4 COP coils from the 4 Speeduino outputs? The signals are already sorted into 4 outputs from Speeduino, so why the circus to combine them just to separate them again? What am I missing? :?
By kettlekev

If you look at the link I sent and the downloadable instructions you will see I'm just trying to match the way their configuration works.

It comes with a new single igniter.

You are right, I could just use the 4 IGN outputs through a 4 channel Bosch igniter direct to COP and get the same result.

Thanks for the single channel steer :D
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kettlekev wrote: Wed Dec 06, 2023 10:13 pmYou are right, I could just use the 4 IGN outputs through a 4 channel Bosch igniter direct to COP and get the same result.
Or more. I see it states wasted-spark in the document. Direct control could also do the same 2-channel wasted spark, 4-ch wasted COP, or fully sequential COP, if those are options you might want. ;)

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