Cheap new coils for COP conversion, opinions?
#1
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I was bored and was doing some research for future mods, including COP conversion, and came across these on ebay: http://cgi.ebay.com/ebaymotors/ws/eB...m=160287926863
New replacement coils for ~$30 each plus shipping, with a 12 month warranty. What are mt.net's thoughts?
New replacement coils for ~$30 each plus shipping, with a 12 month warranty. What are mt.net's thoughts?
#2
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I much prefer paying $50-60 shipped for all four with connectors from a wrecker.
for example:
2000 Ignition Coil Toyota Corolla SET OF 4 $50 Honda & Toyota Menders USA-CO(Denver) E-mail 1-800-480-4544
for example:
2000 Ignition Coil Toyota Corolla SET OF 4 $50 Honda & Toyota Menders USA-CO(Denver) E-mail 1-800-480-4544
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I'm not sure your Link ECU will be up to the task though.
I know for sure you can use them with MS and AEM standalones.
#11
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Here: https://www.miataturbo.net/forum/sho...&highlight=COP
I'm not sure your Link ECU will be up to the task though.
I know for sure you can use them with MS and AEM standalones.
I'm not sure your Link ECU will be up to the task though.
I know for sure you can use them with MS and AEM standalones.
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Cheers for the instructions
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#12
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Yeah the Link G3 can do it no probs, it has 4 Ignition drivers, don't know why it never took off to well with the MX5/ Miatas's especially as they were half the price of Hydra / AEM etc, been superceeded by the G4 Storm now. In the UK the G3's been the choice of ECU for the MR2 guys the last couple of years loads of 600/700bhp cars using them, plenty with COP conversions so I know it'll work ![](https://www.miataturbo.net/images/smilies/smile.gif)
Cheers for the instructions![Biggthumpup](https://www.miataturbo.net/images/smilies/biggthumpup.gif)
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Cheers for the instructions
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Don't forget to change the dwell settings on the ECU!
And keep us posted.
#13
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#17
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If they spark half as much, 1/2 as much heat will be induced into the coils. So good for COP life. Also allows you to now run more dwell to get a little more energy into the spark that you could not have safely run in a wasted spark configuration. Doubles plug life too on regular cars, though this is insignificant on a turbo miata.
#18
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That's the thing. These aren't components that wear out very quickly. I've been running these plugs at 18 psi for a long time now. Years. They look like I just bought them.
As for the COP ignitors, if they were heat sensitive, being mounted on top of the head would probably be a bad place for them. I'd bet that the head supplies way more heat than the cycling of the coils.
Additionally, it seems unlikely that toyota would design an ignition system that would fail if constantly driven at high rpm in hot conditions. Except when you are above 3-4000 rpm, you aren't subjecting them to an unexpected load. And even if you exceed that, I strongly suspect that the margin of error is large for this part.
As for the COP ignitors, if they were heat sensitive, being mounted on top of the head would probably be a bad place for them. I'd bet that the head supplies way more heat than the cycling of the coils.
Additionally, it seems unlikely that toyota would design an ignition system that would fail if constantly driven at high rpm in hot conditions. Except when you are above 3-4000 rpm, you aren't subjecting them to an unexpected load. And even if you exceed that, I strongly suspect that the margin of error is large for this part.
#19
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That's the thing. These aren't components that wear out very quickly. I've been running these plugs at 18 psi for a long time now. Years. They look like I just bought them.
As for the COP ignitors, if they were heat sensitive, being mounted on top of the head would probably be a bad place for them. I'd bet that the head supplies way more heat than the cycling of the coils.
Additionally, it seems unlikely that toyota would design an ignition system that would fail if constantly driven at high rpm in hot conditions. Except when you are above 3-4000 rpm, you aren't subjecting them to an unexpected load. And even if you exceed that, I strongly suspect that the margin of error is large for this part.
As for the COP ignitors, if they were heat sensitive, being mounted on top of the head would probably be a bad place for them. I'd bet that the head supplies way more heat than the cycling of the coils.
Additionally, it seems unlikely that toyota would design an ignition system that would fail if constantly driven at high rpm in hot conditions. Except when you are above 3-4000 rpm, you aren't subjecting them to an unexpected load. And even if you exceed that, I strongly suspect that the margin of error is large for this part.
If you hold dwell constant, then heat induced into the coil is a function of how many times you charge/discharge the coil. Sure, they're temperature changes with the surroundings, but the fact that HEAT induced is a function of charges/discharges remains.
Again, I'm not disagreeing with you. But I think you are bit confused on exactly how the coil works. Heat is not insignificant.
#20
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Yeah, I took physics, just like everyone else. I know that resistance rises as heat rises and that heat is produced by charging and discharging the coils. And I understand that spark strength is a function of the efficiency of this process.
I just suspect that Toyota took this into account when designing the system. I suspect that the internal circuits are robust enough that their performance doesn't degrade at temperatures that won't melt the body of the coil on plug unit. The reasons for such an overdesign should be pretty obvious. If ordinary duty heats up any of the electrically conductive parts significantly enough to degrade their performance, the added heat would further increase resistance in the circuit, which leads to further buildup of heat. This can quickly spiral into a failure of the circuit, maybe even a fire.
My hunch is that toyota designed the COP units to operate indefinitely at full performance during:
-100-150C underhood temperatures, which is reasonable to expect on many vehicles.
-8000 rpm sequential opereation, as on the celica motor.
Which means that running them in wasted spark isn't going to have any significant effect. I think if you ran them at 7000+ rpm for hours on wasted spark, you might get an equilibrium temperature within the plug somewhat higher than when you just putter around town, but realistically I don't think that temperature would ever be high enough to degrade performance. It isn't like the COP unit is thermally shielded from the engine bay and has a separate heat sink to dissipate heat- it shares a single thermal environment with the cylinder head. Both are going to be very hot when running.
And this doesn't even take into account that typical COP conversions are open to engine bay air circulation while OEM COP setups are typically hidden under a huge pile of plastic or metal shielding to keep the engine bay looking pretty.
I just suspect that Toyota took this into account when designing the system. I suspect that the internal circuits are robust enough that their performance doesn't degrade at temperatures that won't melt the body of the coil on plug unit. The reasons for such an overdesign should be pretty obvious. If ordinary duty heats up any of the electrically conductive parts significantly enough to degrade their performance, the added heat would further increase resistance in the circuit, which leads to further buildup of heat. This can quickly spiral into a failure of the circuit, maybe even a fire.
My hunch is that toyota designed the COP units to operate indefinitely at full performance during:
-100-150C underhood temperatures, which is reasonable to expect on many vehicles.
-8000 rpm sequential opereation, as on the celica motor.
Which means that running them in wasted spark isn't going to have any significant effect. I think if you ran them at 7000+ rpm for hours on wasted spark, you might get an equilibrium temperature within the plug somewhat higher than when you just putter around town, but realistically I don't think that temperature would ever be high enough to degrade performance. It isn't like the COP unit is thermally shielded from the engine bay and has a separate heat sink to dissipate heat- it shares a single thermal environment with the cylinder head. Both are going to be very hot when running.
And this doesn't even take into account that typical COP conversions are open to engine bay air circulation while OEM COP setups are typically hidden under a huge pile of plastic or metal shielding to keep the engine bay looking pretty.