Postby droo » Fri Aug 03, 2012 3:46 pm
I'd like to share my experience with the eBay coils.
I purchased mine from PureMX5 via the similarly named ebay store. The coilpacks were also generic.
I built my loom and plugged the cops in, and lo- my roadster started.
I built my dwell circuit the same night and plugged it in with the cops, and lo- my roadster started..
I've been driving about mostly issue free ever since.
The only issue i've had was an inability to start on cold mornings (guessing the battery was likely below 12-13 volts, and insufficient for the dwell circuit to work properly?) but i've since made a startup bypass of the dwell circuit and the car starts flawlessly first time every time of a cold morning (only experience with weather temps so far until summer comes)..
After 200km continuous driving (2.5hrs mostly 110 highway) the coilpacks are only warm to the touch, much MUCH cooler then the rocker cover.
On one trip to melbourne to The Garage restaurant in July, my test wiring between the bypass circuit and dwell reducer had slightly disconnected, causing me to run only 2 cylinders. By bypassing the dwell circuit entirely (keeping my bypass circuit on), i was able to drive.
Knowing full well the dwell circuit reduces the dwell time i was completely and nervously aware that with the alternator providing 13 volts to the engine (and i'm powering my cops directly from an alternator battery positive) would mean the COPs would be getting the standard roadster ECU dwell time - too much for the COPs in the long term. I pulled over after 50km of driving. I checked the temp of the COPs by touching them and literally burnt my finger. Without the dwell circuit reducing the pulse timing they were insanely hot, and my finger took over a week to heal.
(I was rushed, a little stressed from the vehicle breakdown, on a deadline getting to the city and know i should have been less clumsy about it..)
I then checked bypass circuit, saw that the connector had unseated itself (and i'm usually overly conservatively VERY careful about these testing mods and normally secure such things well).. Restarting the engine worked fine (running on all cylinders).
Immense relief and i continued driving. Another 40km down the highway, i rechecked the COPs temps and they had cooled down immensely.
Keep in mind, as a generalisation, most electronics (and the electronics in the head of the COPs) reliability reduces 50% per multiple "25 degrees" over it's designed operating temp. Having them overheat for any extended period is going to cause all sorts of stress and temp loading on the COPs components.
The story here, you *NEED* the dwell-reducer on a stock ECU.
Not having the dwell reducer will overheat the COPs and they will fail. It's not a matter of if
"It won't hippen over night, but will hippen.."
The Genuine Toyota components may have an over temperature function which might reduce the power of the spark, thereby reducing the operating temperature, who knows?!
I'm hazarding a realworld guess that the generic ones definitely don't have that function.
I've now dríven well over 3500km on my setup since i've built it late June, and aside from the, now fixed, cold start issue i had, no other glitches have occur. Incidently i've now clocked just shy of a 1000km since the bypass issue incident i had.
I'm also running my spark plug gaps at 1.2mm (to experiment some other settings) for the past 3 weeks, again, no issues in starting, COP operating temps, or driveability on any driving (city stop/start or highway) etc.
Again, I'm just sharing my experience.
