Sequential COP questions & research
#1
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Yes I did a search, and no, the answer is not clear.
I was wondering if you guys who are running COP with MS1 on an NA, run it in sequential mode, or in wasted-spark mode? I read this and its not clear whether this is possible with the CAS?
http://www.msextra.com/manuals/MS_Ex...l.htm#twotrigs
(scroll down to sequential COP).
I was wondering if you guys who are running COP with MS1 on an NA, run it in sequential mode, or in wasted-spark mode? I read this and its not clear whether this is possible with the CAS?
http://www.msextra.com/manuals/MS_Ex...l.htm#twotrigs
(scroll down to sequential COP).
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on the 1.8 magnetic CAS the mods should be easy enough. there's two sets of sensors. And the plates are both independent so you can just goof around with them until the pulses are in the right place. Unless of course the pulses from the two signal out wires are phased properly already.
![](http://members.aol.com/solomiata2/Miata18CAS2.jpg)
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I havent seen the inside of a CAS but from the DIY website install article, the inner ring of holes has only one hole. So wouldnt that make it one CMP pulse per 720 deg. crank rotation?
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On both the magnetic and optical NA CAS, the CMP signal is one pulse per crank rev, two per cam rev. The two CMP pulses are not of equal duration however, one is high during both the leading and falling edges of the corresponding CKP pulse, the other goes low before the falling edge of the corresponding CKP pulse. (or maybe it was the leading edges of CKP... I've got the printout at home.)
Either way, what you'd need to do is to modify the CAS wheel to eliminate one of the two CMP pulses. I believe you'd want to end up with the one that occurs just before #1 TDC. On the magnetic version, you could simply cut off one of the two teeth. On the optical version, you'd need to fill in one of the slits.
Here's what the inside of the optical CAS looks like:
Either way, what you'd need to do is to modify the CAS wheel to eliminate one of the two CMP pulses. I believe you'd want to end up with the one that occurs just before #1 TDC. On the magnetic version, you could simply cut off one of the two teeth. On the optical version, you'd need to fill in one of the slits.
Here's what the inside of the optical CAS looks like:
![](http://members.aol.com/solomiata2/Miata16CAS.jpg)
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Since its an optical sensor on the 90-93 and it doesnt care about proximity, maybe there is enough space to solder or maybe glue a tiny piece of aluminum sheet on the backside of the existing plate?
I need to get a spare CAS and try this myself.
On the MS two additional outputs need to be brought out to the harness.
I need to get a spare CAS and try this myself.
On the MS two additional outputs need to be brought out to the harness.
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I posted this on the Extra forum today:
http://www.msextra.com/viewtopic.php?t=28252
Maybe I should've asked here first.
I think sawing off the magnetic CAS seems like a more reliable option, PROVIDED 4 pulses are enough on the CKP signal.
If an escort GT distributor is similar to a 94-97 CAS I'm gonna find me one in the yard today.
http://www.msextra.com/viewtopic.php?t=28252
Maybe I should've asked here first.
I think sawing off the magnetic CAS seems like a more reliable option, PROVIDED 4 pulses are enough on the CKP signal.
If an escort GT distributor is similar to a 94-97 CAS I'm gonna find me one in the yard today.
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Ok I went to the yard and picked up a CAS. I have some interesting findings for you guys:
1) A Ford Festiva has the exact same optical CAS as the 90-93 miata, except that there is only one inner slot. It looks the same as the pic Joe posted, except that the inner lower slot isn't there. This would give the required 4 + 1 pulse.
2) I picked up a Ford GT distributor which is the exact same magnetic CAS as the 94-97 miata, except that there is only one inner "ear". This would give a 4 + 1 pulse as well.
So all those who're looking for a cheap CAS go to the yard and find yourself a Ford Festiva. Nobody wants parts off of those. Got the CAS for $20.
Sequential COP, here I come!!
1) A Ford Festiva has the exact same optical CAS as the 90-93 miata, except that there is only one inner slot. It looks the same as the pic Joe posted, except that the inner lower slot isn't there. This would give the required 4 + 1 pulse.
2) I picked up a Ford GT distributor which is the exact same magnetic CAS as the 94-97 miata, except that there is only one inner "ear". This would give a 4 + 1 pulse as well.
So all those who're looking for a cheap CAS go to the yard and find yourself a Ford Festiva. Nobody wants parts off of those. Got the CAS for $20.
Sequential COP, here I come!!
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There are two types of escort GT distributor, the one above and the magnetic type posted by y8s, except with one inner ear.
The point is, now that the requisite signal is in place, how to get 4 outputs out of the MS. I'll be researching and implementing this in the coming week.
The point is, now that the requisite signal is in place, how to get 4 outputs out of the MS. I'll be researching and implementing this in the coming week.
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Pipe, seriously...you think this will work?
I am very ignorant when it comes to electronics, but I do inderstand when someone explains something.
So, are you saying that, if I get an Escort GT CAS (I have a 94 1.8) that it will fit right in place of my CAS and i'll be able to run two extra wires (which you will explain I am sure) from my MS (standalone) to my coils and have sequential ignition?
Will this be possible on 94+ cars?
Will this work on parallel installs? I am asking for others...
Will this work on NBs? Also for others...
Thanks,
Dan
I am very ignorant when it comes to electronics, but I do inderstand when someone explains something.
So, are you saying that, if I get an Escort GT CAS (I have a 94 1.8) that it will fit right in place of my CAS and i'll be able to run two extra wires (which you will explain I am sure) from my MS (standalone) to my coils and have sequential ignition?
Will this be possible on 94+ cars?
Will this work on parallel installs? I am asking for others...
Will this work on NBs? Also for others...
Thanks,
Dan