The only stand-alone system that I know is the Electromotive XDi but it looks like the company is up for sale and is not selling product at this time.
You could look at using the Megasquirt 3 unit and just use the ignition section.
What ignition system is “best”
- Thread starter vssman
- Start date
You could look at using the Megasquirt 3 unit and just use the ignition section.
The more I consider it, the more I think the output from the 6AL-2 could be directed to the 6 coil pack with a sequencer circuit, with the sequence regulated with a camshaft synchronizer (that'll also drive the oil pump). This can't be that hard of a circuit to design. In a former life, I used to work in a circuit board factory, so I think I can make something durable enough for automotive conditions. I like a challenge...
The output is 530 to 540 volts.
If the output is partially isolated from ground it could be difficult to design a steering circuit.
You would need to analyze the MSD output circuit.
Last edited:
I was thinking about the Holley Smart Coils. Looks like a 5V signal to trigger:
Since they say that "any gauge wire is acceptable", I'm led to believe these draw minimal current.
The coil driver inside the coil itself uses high current but the 5-volt trigger signal is a very low current.
The trigger signal needs to be a 5-volt square wave with a 4 msec duration.
You would still need something like a Megasquit 3 unit to trigger the coils.
Last edited:
DS11 is easier to recurve. It also supplies a stronger signal.
I like the MSD 6425 ignition box supplies several sparks up till 3K.
The MSD Blaster coil is also very good.
MSD also supplies a harness to connect the DS11 to the box. Its the MSD 8869.
Make sure you use spiral wound plug wires.
I recurve distributors the correct way. If i make an adjustment i know what i have with no
guessing. Bill
I like the MSD 6425 ignition box supplies several sparks up till 3K.
The MSD Blaster coil is also very good.
MSD also supplies a harness to connect the DS11 to the box. Its the MSD 8869.
Make sure you use spiral wound plug wires.
I recurve distributors the correct way. If i make an adjustment i know what i have with no
guessing. Bill
Bronctopia
Well-known member
Pretty much, but for something reasonably life critical like the ignition circuit for a passenger vehicle, you would need what is called a Real Time Operating System. Most ECU use an even simpler Embedded System.
It comes down to reliability.
Raspberry Pi systems are General Operating Systems.
Basically an enormous 'grab bag' of hardware and code, that is versatile, but not very predictable.
There is no guarantee that your If-Then decision code, running in user space alongside a swarm of other background OS processes, is going to get to process it's statements and generate its outputs at the exact millisecond that firing a cylinder requires.
If you want to look into coding your own ignition logic, an embedded platform like Arduino is preferred. There is even an open source effort called Speeduino.
A good place to start ground up would be to dive through their code, do some simple Arduino projects first, and then if you still want to "roll your own", constructing a bench "simulator" or "stimulator" system is the safe(r) and sane way to develop and debug.
((I'm not suggesting you abandon the coil-on-plug)) but as this gets increasingly complex and reliability may diminish--- a distributor is a really effective switcher.
Bronctopia
Well-known member
Everything will eventually cycle back to this statement in the second post.
Asking what "The Best" ignition system is... Is too use case dependent.
It is like asking what "The Best" aircraft is. First you will have to specify what you really need it to do.
Does your ignition system need to ignite boosted mixture at 9000rpm in a V12? Then you probably DO want to step away from the distributor and go to individual coils.
Each coil is now going to cost what the 1 distributed coil costs. You will absolutely need an engine management system to figure out when to charge and fire them, etc.
Does your ignition system need to ignite mixture in a single engine piston powered aircraft?
Reliability is now almost your only criteria. If you even have just 1 ignition system, it is probably magnetos, much like your lawnmower.
Even if we agree that we are mostly only talking about low revving, naturally aspirated, probably carbureted, antique inline sixes, that are far from stretching the limits of traditional distributor ignitions, what do you value most here?
Are you willing to live with the wear maintenance of points for authenticity sake? Did you modify it to the point that it idles like a mortar mixer? Maybe even just because you like the way that sounds? CDI is now your best friend....
In my case the affliction is the slippery slope of over-thinking, coupled with the endorphin rush of problem solving. At the end of the day (i actually hate that cliché), this, for me, is a hobby. Building things is a source of entertainment that i enjoy more than most other things. I've long wanted to figure out crank triggered setups, and I've been advised that these engines are somewhat finicky about their timing. While I could just get a professionally curved distributor built for me, that just doesn't seem to scratch that itch. Besides, it gives me an excuse to dive down the "programming an Arduino" rabbit hole. My timeline for finishing this project? Undefined. For me, it's more about the journey than the destination.
My late wife would roll her eyes, in amusement, and label it: "Another thing that John decided to build". She'd sing my praises behind my back to her friends, but liked to rib me for the way I am. She's been gone for a year today. God I miss her...
Bronctopia
Well-known member
That is a perfectly valid aesthetic here among all of us who are running auld iron that is several administrations past it's crush-by-date.
I have much of the same affliction as you. And others besides.
The older I get the more I realize that traits in others a younger me would scoff at, are probably in myself all along, just manifesting in different ways.
That quip I made about making a car with a crash-cart idle just for the sound (&vibes)? It's probably the same urge that kept me addicted to big bore dual-sport thumpers when everyone else is going to parallel twins.
And the more I think about it, I do have a huge sound and rhythm nostalgia for the exhaust note of idling big bore four strokes inline 3s.
Mostly in diesel tractor engines.
If I every get to the downhill inflection of that "programming an Arduino/Embedded" learning/implementing curve, the first non-practical thing I will do with it is create an Idle-Lope-Mode that emulates the "Po-TAY-toe Po-TAH-toe" syncopation of a big Ford tractor inline 3 in an inline 6.
I could even do it in batch fire, killing both fuel and spark to alternating banks of 3 cyls to keep the temps stable.....
I have much of the same affliction as you. And others besides.
The older I get the more I realize that traits in others a younger me would scoff at, are probably in myself all along, just manifesting in different ways.
That quip I made about making a car with a crash-cart idle just for the sound (&vibes)? It's probably the same urge that kept me addicted to big bore dual-sport thumpers when everyone else is going to parallel twins.
And the more I think about it, I do have a huge sound and rhythm nostalgia for the exhaust note of idling big bore four strokes inline 3s.
Mostly in diesel tractor engines.
If I every get to the downhill inflection of that "programming an Arduino/Embedded" learning/implementing curve, the first non-practical thing I will do with it is create an Idle-Lope-Mode that emulates the "Po-TAY-toe Po-TAH-toe" syncopation of a big Ford tractor inline 3 in an inline 6.
I could even do it in batch fire, killing both fuel and spark to alternating banks of 3 cyls to keep the temps stable.....
