COP Thread
#1485
Senior Member
![](/mt2011/images_td/ranks/supporter1.gif)
iTrader: (1)
Join Date: Jan 2011
Location: Chattanooga, Tn
Posts: 1,234
Total Cats: 283
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
You don't need to cut the plug wire. Just take the #1 COP out of the hole, plug the end of a plug wire that hooked to the factory coil pack into the COP, and then install the plug wire on the spark plug as you normally would. Now you can put the pick up on the spark plug wire. I keep a plug wire in the tool box on the trailer just for this.
#1487
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Ive been working on my COP kit for my 94 and I have come to a point where I want to make it easy to go back and forth between COPs and stock(smog check contingency).
Ive come to the conclusion the female plug in the picture is the key to make it my harness plug and play connector wise, and not have to cut any of the car side harness wires.
Ive been searching but, anyone know where I could buy one, or what car I scavenge one off at a Pick-a-part and re-pin it.
Ive come to the conclusion the female plug in the picture is the key to make it my harness plug and play connector wise, and not have to cut any of the car side harness wires.
Ive been searching but, anyone know where I could buy one, or what car I scavenge one off at a Pick-a-part and re-pin it.
![](https://www.miataturbo.net/attachments/diy-turbo-discussion-14/28578-cop-thread-ignitionconnector-1.jpg?dateline=1321930201)
#1488
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
On the '99, the key connector is right at the front of the engine, but it's similar to that one. Compatible connectors are all over mid-'90s Mazdas at the Pick Your Part. Just print out the photo you posted and take it with you. Grab a few in case there are differences you don't catch until you get home.
#1489
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
You'd need to get a connector from another 94/95. later years have a 4 pin plug there instead of the 6 pin plug. Best bet would be to find a 94/95 at a junk yard and hack out part of the harness. The wires for the coils are just taped in and pretty much don't share any wires. so don't cut any wires, just tape/heatshrink
It probably wouldn't be worth getting anything from the dealer as they'll rape you price wise for a entirely new wiring harness if they can get it
It probably wouldn't be worth getting anything from the dealer as they'll rape you price wise for a entirely new wiring harness if they can get it
#1492
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
One thing you could do if you want to keep it plug n play in the future is replacing that plug on both the main harness and the coil part of the harness. So you'd buy two 6 or 8 pin female connectors and one male. of course this would require you to splice in the connectors initially but after that it'd be plug and play as long as you kept the original part if the harness that connects directly to the factory coils (the two 4-pin connectors). Not sure if i'm making sense a i'm typing on my phone
Last edited by bmxfuel007; 11-24-2011 at 05:17 AM.
#1493
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
So I've read this whole thread almost twice. Unless I missed something or my inexperience is obvious. As far as dwell goes 2.5ms at 12v I understand. However what do I do with the rest of the dwell curve in the Hydra ecm. At the moment it's at 5.4ms at 12v. So is as simple as easy math. 5.4ms-2.5=2.9 and then just lower all the other numbers in the curve by 2.9ms? IE; 12v-2.5ms / 11.7v-(5.76-2.9=X)2.86ms / 11.3-(6.2-2.9=X)3.3ms and so on? Also can't find a "cranking dwell" in the Hydra 2.5 software. I am a total noob to this so I'm sorry. Thanks for any help. Wires, capacitors, weatherpacks, and heatshrink are making a baby in the morning.
#1494
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
![](http://www.newunitedracetech.com/shop/images/Products/9565.jpg)
Here are sources for the pins:
http://www.bmotorsports.com/shop/ind...pfke95ub6s0sk6
http://www.easternbeaver.com/Main/El...SMDL/smdl.html
Last edited by skou; 11-27-2011 at 04:49 AM. Reason: Added linked images
#1495
Elite Member
iTrader: (12)
Join Date: Jan 2007
Location: Hermosa Beach, CA
Posts: 2,573
Total Cats: 12
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
So I've read this whole thread almost twice. Unless I missed something or my inexperience is obvious. As far as dwell goes 2.5ms at 12v I understand. However what do I do with the rest of the dwell curve in the Hydra ecm. At the moment it's at 5.4ms at 12v. So is as simple as easy math. 5.4ms-2.5=2.9 and then just lower all the other numbers in the curve by 2.9ms? IE; 12v-2.5ms / 11.7v-(5.76-2.9=X)2.86ms / 11.3-(6.2-2.9=X)3.3ms and so on? Also can't find a "cranking dwell" in the Hydra 2.5 software. I am a total noob to this so I'm sorry. Thanks for any help. Wires, capacitors, weatherpacks, and heatshrink are making a baby in the morning.
The best was is to test. Lower the dwell until you get misfiring under full boost, then back it back up ~.2ms.
#1497
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
I guess that sort of answers part of the next question. What if the dwell is too long/short, how would I know. Other than too short the car cuts out do to no spark and too long and the COPs melt. Is slightly to long better than running on the hairy edge of too short. I took your suggestion on ^ and just subtracted 1.8 from everything across the board to keep the same curve as before and it puts me in the middle of your suggestion at 2.72ms at 13.6v and kept that curve up and down the voltage range. 4.88ms at 11v - 3.6ms at 12v - 2.72ms at 13.6v - 2ms at 15v all interpolated in between. I guess for a base line it keeps my FM basemap shape at the lower COPs range.
Other question is why the lower dwell on the COPs? I know coil on plug is a different idea/design than the factory wires and coils, but it's the same amount of cylinders and same rpm range? and if they product more spark, then how do they do it with less juice? or am I thinking too much and just need to shut up, plug the numbers in, and go away? I dwell too much on the mechanics of everything sometimes. (See what I did there? Dwell.....haha)
Other question is why the lower dwell on the COPs? I know coil on plug is a different idea/design than the factory wires and coils, but it's the same amount of cylinders and same rpm range? and if they product more spark, then how do they do it with less juice? or am I thinking too much and just need to shut up, plug the numbers in, and go away? I dwell too much on the mechanics of everything sometimes. (See what I did there? Dwell.....haha)
#1498
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Got it all on the car. Won't start. With key on I get power (12v) at the COPs connectors and in the right polarity. It's a '99 so the tach wires are sealed off and tucked in the harness in case I want them later. How do I test to make sure I have a "trigger" connection? Pull the COP and put a plug in it, rest it agains the manifold, and turn over the car looking for spark? or unplug it at the COP and turn the key over with a multimeter hooked to it and ground? I know certain cars if you unplug the coil and try to turn over the motor it melts things. I believe it's just GM CDI cars though.
It may be the serious overfueling on cranking just keeping it from firing. My wife can smell fuel from the porch. It would eventually start on the stock coils though.
It may be the serious overfueling on cranking just keeping it from firing. My wife can smell fuel from the porch. It would eventually start on the stock coils though.
#1499
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Got it all on the car. Won't start. With key on I get power (12v) at the COPs connectors and in the right polarity. It's a '99 so the tach wires are sealed off and tucked in the harness in case I want them later. How do I test to make sure I have a "trigger" connection? Pull the COP and put a plug in it, rest it agains the manifold, and turn over the car looking for spark? or unplug it at the COP and turn the key over with a multimeter hooked to it and ground? I know certain cars if you unplug the coil and try to turn over the motor it melts things. I believe it's just GM CDI cars though.
It may be the serious overfueling on cranking just keeping it from firing. My wife can smell fuel from the porch. It would eventually start on the stock coils though.
It may be the serious overfueling on cranking just keeping it from firing. My wife can smell fuel from the porch. It would eventually start on the stock coils though.
#1500
Elite Member
iTrader: (37)
Join Date: Apr 2010
Location: Very NorCal
Posts: 10,448
Total Cats: 1,900
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
I have a 2000 and to test, I stuck an extra plug in each one of the COPs and set them so they were grounded to the top of the valve cover. I had an 'assistant' crank the motor so I could watch the light show.
IIRC, you should have 12v on the power connector when in 'RUN' or 'CRANK' and the trigger is just a pulse. Someone will correct me if I'm wrong I'm sure.
Are you running stock ECU or some other management? My stock '00 ECU runs wasted spark from the factory, so two of the COPs fire at the same time. Double and triple check that you have the correct pairs going to the appropriate cylinders.
Edit: Bah! Sorry Torque, didn't read back far enough. Can't help you on the FM ecu stuff, but the rest should still be OK. If worst comes to worst, you can always get a spark tester pretty cheap from any auto parts store.
![](https://www.miataturbo.net/attachments/diy-turbo-discussion-14/30453-cop-thread-31zd5t1arrl._sl500_aa300_.jpg?dateline=1325007393)
IIRC, you should have 12v on the power connector when in 'RUN' or 'CRANK' and the trigger is just a pulse. Someone will correct me if I'm wrong I'm sure.
Are you running stock ECU or some other management? My stock '00 ECU runs wasted spark from the factory, so two of the COPs fire at the same time. Double and triple check that you have the correct pairs going to the appropriate cylinders.
Edit: Bah! Sorry Torque, didn't read back far enough. Can't help you on the FM ecu stuff, but the rest should still be OK. If worst comes to worst, you can always get a spark tester pretty cheap from any auto parts store.
![](https://www.miataturbo.net/attachments/diy-turbo-discussion-14/30453-cop-thread-31zd5t1arrl._sl500_aa300_.jpg?dateline=1325007393)