Tips required to fit COPs to my '96 NA8

lonesailor · Postby **lonesailor** » Tue Aug 17, 2021 1:36 pm

I have read the excellent guides in this section, however I still have questions I need answers to before starting the project to fit them to my car. My main purpose for the project is to clear some space on the back of the engine to avoid a repeat of the nightmare I have just been through, sorting out wiring to fix a disconnected coolant temp sensor and to fit a temperature gauge which would warn me of an overheat situation BEFORE the engine is stuffed. I also have plans for a coolant re-route, which would be much easier with more space. The existing posts refer to an igniter which my car, if it has one, is hiding it well. Is the '96 model different here? Another query is regarding spark dwell times and voltage, are these adjustable on the '96 with the OEM ECU, or on the coils themselves? or does one need an aftermarket computer? My plan is to try to source some 2nd hand Toyota coils including the connectors, and to either find suitable sockets for the existing plugs coming from the existing coils at the wreckers, or if that is unsuccessful, source suitable new connectors. I suppose, if I had to, I could simply mount the existing coils elsewhere and rewire the low voltage side to them, COPs, however would be a much more elegant solution. All critiques of my plan or suggestions would be welcome. My car is basically stock and naturally aspirated.

bartmanftw · Postby **bartmanftw** » Tue Aug 17, 2021 2:50 pm

I think the guide you are refering to is for an NA6 89-93 which has a different spark system. The later models had 'smart' coils with inbuilt igniters so no need for an external one.
The OEM ECU is not adjustable so you'll either have to hope that it won't over dwell the coils or fit an aftermarket ECU which seems silly just to run Toyota coils. There's only 3 bolts holding in the OEM coils, is it that much of a hassle to remove to gain access to that area of the engine?

If you're set on fitting them then it is possible to make a PnP harness for the Toyota coils. If you follow the coil harness from the two 4-way connectors that plug into the OEM coils, it should lead to another 4-way or 6-way connector (depends on NA8 model year). You can find a mating connector for that so that your new harness will plug in with no wiring changes to the cars original harness.

lonesailor · Postby **lonesailor** » Thu Aug 19, 2021 2:01 pm

Have you ever tried to fit a different temperature sensor into the 1/8'"NPT hole back there even with the coils removed and the CPS sensor removed? I have and still have the scars on my hands to prove it! Your idea to replicate the existing wiring from the connector before the original coils has merit, I'll have a good look at it. I'm still a bit concerned that the signal will be sufficient for optimum spark.

bartmanftw · Postby **bartmanftw** » Thu Aug 19, 2021 4:22 pm

No but I have fitted a number of coolant re-routes back there.

What is your concern with using the original wiring? If you think the new coils will draw a lot more current then use thicker wires and source the 12V and ground from somewhere else but the Toyota COPs will work fine through the OEM wiring.