I'm planning on changing my '94 miata over to the Toyota COPs
- Thread starter Griffit
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ShelbyRacer
New member
Yes, in IT it is legal, from what I know of the conversion.
I don't know the conversion details, but we've discussed CoPs in the past and decided they're NOT compliant to the IT regs (which is kinda silly, but...)
The jist of the argument is that the IT regs (from memory) require the original distributor for DISTRIBUTION of the spark. Since a CoP conversion dispenses with the spark plugs wires, which distributes the spark from the distributor to the plugs, it is non-compliant.
Post the details and we can discuss it, but my suggestion is "no".
GA
ShelbyRacer
New member
It was my understanding that the Mi-otter uses a coil pack and not a distributor. If I am incorrect on that, then that is the issue.
If it is distributorless, then you'd be going from one coil pack with 2 coils inside to 4 separate coils, and probably firing two at a time, thereby maintaining the original method of distribution. Since any ignition system using the original distributor is allowed, I see no compliance issue.
If it is distributorless, then you'd be going from one coil pack with 2 coils inside to 4 separate coils, and probably firing two at a time, thereby maintaining the original method of distribution. Since any ignition system using the original distributor is allowed, I see no compliance issue.
You're right, Matt: the 1.8L Miata does not have a "distributor". It has a distributor-like timing device and coil packs that mount to the firewall end of the head, and spark plug wires come off that.
And that brings up an interesting point:
"Any ignition system which utilizes the original distributor for spark timing and distribution is permitted."
Does the word "distributor" mean the automotive term that refers to a shaft-driven device with a cap, rotor, and wires? Or is it more adjective that refers to whatever device distributes the spark?If you car did not come with an automotive-term "distributor", how does this reg apply? Does this restriction apply?
Since the Miata originally used a pair of coil packs that had spark plugs wires coming off of them to "distribute" the spark to the plugs, is it compliant to dispense with those spark plugs wires entirely and move coils, which are free to be replaced, directly on top of the plug wires?
And if so, why are distributor-equipped cars inequitably being hobbled by not being allowed to do the same?
I don't think, based on the my interpretation of the spirit of the regs, you can completely eliminate a spark plug wire distribution system and convert to CoP. After all, the intent of the reg was to make you stay with distributed high-tension wires if your car came with them. This reg is likely original from 1985 when CoP was rare (if it even yet existed). But if you can remove that spark distribution system, then it sounds like yet another "Advantage: Miata", and another "those words were great in 1985 but suck today" kinda thing.
If it is intended, then reg should be changed to read like the crankfire ignition reg: "Coil-on-Plug ignition is prohibited unless fitted as original equipment." If that's not what's intended, then open it up so everyone can do it fairly.
GA
And that brings up an interesting point:
"Any ignition system which utilizes the original distributor for spark timing and distribution is permitted."
Does the word "distributor" mean the automotive term that refers to a shaft-driven device with a cap, rotor, and wires? Or is it more adjective that refers to whatever device distributes the spark?If you car did not come with an automotive-term "distributor", how does this reg apply? Does this restriction apply?
Since the Miata originally used a pair of coil packs that had spark plugs wires coming off of them to "distribute" the spark to the plugs, is it compliant to dispense with those spark plugs wires entirely and move coils, which are free to be replaced, directly on top of the plug wires?
And if so, why are distributor-equipped cars inequitably being hobbled by not being allowed to do the same?
I don't think, based on the my interpretation of the spirit of the regs, you can completely eliminate a spark plug wire distribution system and convert to CoP. After all, the intent of the reg was to make you stay with distributed high-tension wires if your car came with them. This reg is likely original from 1985 when CoP was rare (if it even yet existed). But if you can remove that spark distribution system, then it sounds like yet another "Advantage: Miata", and another "those words were great in 1985 but suck today" kinda thing.
If it is intended, then reg should be changed to read like the crankfire ignition reg: "Coil-on-Plug ignition is prohibited unless fitted as original equipment." If that's not what's intended, then open it up so everyone can do it fairly.
GA
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ShelbyRacer
New member
Advantage, not only Miata, but Neon, and any other car that has coil packs, but not individual.
Technically, distributor cars *could* do this mod. You'd need to change the distributor to the "low" side of the ignition system, and use it to fire the coils, but that's technically allowed since "Internal distributor components and distributor cap may be substituted." Tortured perhaps, stupidly complicated yes, but technically sound.
This reeks of the "open ECU vs. stock box vs. stock ECU" issue, though this is certainly easier to police (or is it?).
Since ECUs are open, cars with a distributor are at a distinct handicap unless you go to insane lengths to control individual cylinder timing. It's doable, but is it worth it?
Can anyone explain to me the hellfire that would rain down if the rule were changed to simply-
Technically, distributor cars *could* do this mod. You'd need to change the distributor to the "low" side of the ignition system, and use it to fire the coils, but that's technically allowed since "Internal distributor components and distributor cap may be substituted." Tortured perhaps, stupidly complicated yes, but technically sound.
This reeks of the "open ECU vs. stock box vs. stock ECU" issue, though this is certainly easier to police (or is it?).
Since ECUs are open, cars with a distributor are at a distinct handicap unless you go to insane lengths to control individual cylinder timing. It's doable, but is it worth it?
Can anyone explain to me the hellfire that would rain down if the rule were changed to simply-
Any ignition system is permitted. Ignition
timing is unrestricted. Batteries may be replaced with those of
alternate manufacture provided they are of similar amp-hour
capacity and weight and are fitted in the standard location.
Additional battery hold-down devices may be used, and are
strongly recommended. Cars originally equipped with two (2)
6-volt batteries may replace them with one (1) 12-volt battery
installed in either of the original battery locations.timing is unrestricted. Batteries may be replaced with those of
alternate manufacture provided they are of similar amp-hour
capacity and weight and are fitted in the standard location.
Additional battery hold-down devices may be used, and are
strongly recommended. Cars originally equipped with two (2)
6-volt batteries may replace them with one (1) 12-volt battery
Nope. Some ITAC members have, on this board, said that in their personal opinions, "distributed" means high tension spark plug wires.
Case in point: Hondas have a distributor system, with the Hall Effect sensor, coil, and ignitor all inside the distributor housing, with regular ole rotor, cap, and spark plug wires to standard plugs. They tend to over heat and fail these internal ignitors and coils so some in IT would like to go to a CoP.
Hondata, a manufacturer of an IT-compliant aftermarket ECU system, offers a CoP module that interfaces with their ECU and allows use of Honda OEM CoPs. The module uses the stock distributor innards for timing, but ignores the coil and ignitor. It then adds a wiring harness from the distributor to the CoP module and from the module plugs into these OEM CoPs to fire the coils.
This would, in effect, allow the Hondas to do EXACTLY as you are suggesting above that the Miatas can do: use a cam-driven device as the engine position sensor, install CoPs on the plugs, and use a CoP module to fire them.
However, the ITAC members have declared this is non-compliant (in their opinion), because while the distributor is still there, it is no longer "distributing" the spark as is required by the regs, since all the (automotive-term) distributor is doing now is acting as a timing device to the ECU (same as Miata). Others have suggested that you could wire the Honda such that the wires going to the CoPs come out of the distributor, but the response was that no, that's not compliant because that would be distributing a signal to fire the CoPs, not delivering the actual "spark".
Thus, according to them, it can never be compliant to install a CoP system on any car that has a distributor, because the spark is no longer being "distributed" by that distributor.
I'll not bother to be accused again of tempting others into STL (where we can already do this, har-de-har), but IT should change the rule to let everyone install CoP if desired. That's another one of those 1985 washer bottle regs that no longer apply to today's technologies.
Out.
GA
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ShelbyRacer
New member
Greg-
After posting, I did find that generally speaking, the distributor is a "high" side item by definition. I would also say that my suggestion is a somewhat tortured interpretation, and was made for illustrative purposes. I had NO idea that someone actually made a retro-fit system like that, though I guess it makes some sense...
But, you can't have it both ways. If you are using the technical definition for a distributor in an automotive ignition system, then according to that definition, the Miata doesn't have one, rendering the point moot.
I would still maintain though, that the CoP mod is legal for cars like the Miata and Neon, where you are simply changing the from one integrated coil to several individual coils, though they are still batch-fired as originally "designed" electrically.
The argument is academic at this point (as so many interwebz forum threads are), as it may all come down to what several people think when presented with paperwork, and that all could be overruled by several other people after more paper is thrown.
And Greg- your post above is EXACTLY why I feel it's not the place of the ITAC (or any other AC) to offer *official* interpretations of rules. IMHO, they (we) are a group that provides recommendations only. If a rule was unclear, then it certainly IS the job of the applicable AC to address that. The sticking point then becomes, if some on the AC feel the rule is clear, it would take a very specific request to invoke a response that carries any significant clarity.
To the OP- I'd suggest a request letter is in order- to change the rule to clearly allow this setup if you feel it's worth the effort.
After posting, I did find that generally speaking, the distributor is a "high" side item by definition. I would also say that my suggestion is a somewhat tortured interpretation, and was made for illustrative purposes. I had NO idea that someone actually made a retro-fit system like that, though I guess it makes some sense...
But, you can't have it both ways. If you are using the technical definition for a distributor in an automotive ignition system, then according to that definition, the Miata doesn't have one, rendering the point moot.
I would still maintain though, that the CoP mod is legal for cars like the Miata and Neon, where you are simply changing the from one integrated coil to several individual coils, though they are still batch-fired as originally "designed" electrically.
The argument is academic at this point (as so many interwebz forum threads are), as it may all come down to what several people think when presented with paperwork, and that all could be overruled by several other people after more paper is thrown.
And Greg- your post above is EXACTLY why I feel it's not the place of the ITAC (or any other AC) to offer *official* interpretations of rules. IMHO, they (we) are a group that provides recommendations only. If a rule was unclear, then it certainly IS the job of the applicable AC to address that. The sticking point then becomes, if some on the AC feel the rule is clear, it would take a very specific request to invoke a response that carries any significant clarity.
To the OP- I'd suggest a request letter is in order- to change the rule to clearly allow this setup if you feel it's worth the effort.
Interesting. Seems I took a different tack just a year ago.
Demonstrates the "rule is correct as written".
pitbull113
New member
Greg you'd make a great politician
ShelbyRacer
New member
Interesting. Seems I took a different tack just a year ago.
Demonstrates the "rule is correct as written".
Damn, now I'm making the same arguments as Greg, while trying to dispute Greg.
I'm going home.
Oh crap, I am home.
If I got to rewrite this rule today, I'd make the open coils match in number to the OEM - so the 2 coil miata (correct?) would be allowed to run any 2-coil setup desired. stock CoP, any CoP (or coil per plug). I'd also say that the crankfire (or any other term for electronic spark distribution) cars should remain stuck with the tone wheels supplied to them by the OEM, while still allowing the distributed guys open sensors inside the distributor.
but yeah, now there is no clear answer. the rule is older than the technology it's governing.
but I do not support CoP conversions of the type proposed by GA. too far from the IT philosophy IMHO.
but yeah, now there is no clear answer. the rule is older than the technology it's governing.
but I do not support CoP conversions of the type proposed by GA. too far from the IT philosophy IMHO.
ShelbyRacer
New member
I don't think Greg is proposing anything specific. And the problem is if the number of coils must match, the Miata, and Neon, and others are prevented from going CoP, which I truly believe is currently allowed by the wording as it stands. The coil-number rule wording would be more limiting. If that's what is desired, then OK, but I'm not sure what the point really is.
In my mind, the current rule does work to some extent--
If you have a distributor (unintelligent technology), you can play with the single advance curve via mechanical, vaccuum, or electronic control.
If you have coils, you can run semi-intelligent technology and run separate advance curves per coil. The ONLY cars that see any real advantage are cars that batch-fire the spark,in that they *could* use a coil-per-cylinder and sequence it.
The question really is, are those cars going to suddenly see performance gains from this type of mod? The other question is, would distributor cars truly benefit from going distributorless? Or, is this all one of those slippery-slope type of deals (which I fear it may be...)?
In my mind, the current rule does work to some extent--
If you have a distributor (unintelligent technology), you can play with the single advance curve via mechanical, vaccuum, or electronic control.
If you have coils, you can run semi-intelligent technology and run separate advance curves per coil. The ONLY cars that see any real advantage are cars that batch-fire the spark,in that they *could* use a coil-per-cylinder and sequence it.
The question really is, are those cars going to suddenly see performance gains from this type of mod? The other question is, would distributor cars truly benefit from going distributorless? Or, is this all one of those slippery-slope type of deals (which I fear it may be...)?
most distributed cars would need better pickups (better resolution) to run distributorless. if they are allowed that mod they would be, in turn, allowed the same for the engine management as the ignition and EFI would lilkey be controlled by the same box.
hondas and a numbe rof other holdouts had good data coming from their distributors, and thus the data is there to run CoP should you wish. but the rules don't allow it and I don't think that they should.
limiting coils to the stoick number isn't a strategic thought, it's simply one that minimizes changes from stock.
hondas and a numbe rof other holdouts had good data coming from their distributors, and thus the data is there to run CoP should you wish. but the rules don't allow it and I don't think that they should.
limiting coils to the stoick number isn't a strategic thought, it's simply one that minimizes changes from stock.