"Coil on plug" coils for 1UZFE

[cribbj]

Username, please expand on your comment "....eg no provisions for 5v to 2.5v to 0v step switching."

I've often wondered why Toyota didn't trigger the igniter for the 2JZ motor with a simple 5v to 0v transition. Why did they go from 5v to 2.5v? Perhaps there's more to this than meets the eye at first?

FWIW, I hope to use the "later" 1UZ COP's wired in waste spark, running from the AEM PnP box for the Supra. It has only 5 ignition outputs, hence the need for the waste spark configuration. This box doesn't require the IGF signal, so I plan to use the 4 wire coils, but will leave the IGF disconnected.

You also mentioned using relays in your post; for what purpose were these to be used?

John

 

[username]

If your box is using ground to complete the circuit for spark (like every other EMS I have seen/used), then you will need to run a relay to switch the coil from 5v to 0V. The EMS will control the relay which controls the 5v switchable. The problem is that standard relays will never react fast enough nor have a high enough frequency rating for this application... no dice...

I like the idea of the 2uz/1mz COP for fitment reasons, but I think a two wire unit is much more usable. One of these days I will find some time and take measurements on the various two wire COPs. Certainly, one of them has to be pretty close. I wouldnt be surprised if honda made something close. I hope somebody figures something out before I do.

 

[cribbj]

Aren't you describing the function of the igniter? The ECU switches a TTL level 5v logic signal to the igniter, which then switches the 12v power on/off to the coil. The igniter is the relay, or am I missing something?

John

 

[username]

Depends on the box you are using

 

[Zuffen]

Username,

Sorry for the delay.

They are two wire and the attached photo shows what they look like with the rubber boot removed.

The wire spring is 10mm short of reaching the plug. Nothing a quick stretch wouldn't fix.

I imagine you could remove the kinked section of boot and substitute an alternative boot that would give good insulation and hold the spring in place.

 

[mycarhasposessedme]

Great thread, watching eagerly.
Cheers

 

[SprinterTRD]

The Toyota COP is known as a Falling edge trigger and have inbuilt ignition modules. As stated the input to the COP goes from 0V to 5V at the start of the dwell period then goes low to generate the spark. Different Toyota COP use a different dwell time usually 1.8ms or 3.0 ms I have the figures at work. The dwell is controlled by the ECU.

The standard toyota igniters have inbuilt dwell control and is not controlled by the ECU.

There are a number of the ford style COP's, Mustangs, Ford V10 & Focus use different versions. You will need to get the polarity correct there is a small B+ on the coil connector. They need an external ignition module for them to function and usually need 1.7ms Dwell.

Subaru also have a COP as do Nissan.

Selecting a COP will depend on whether or not your ECU can control the Dwell time as some brands do not.

 

[autronic]

Waiting for the dust to settle to see what COP is the one to use.....

 

[cribbj]

The dwell is controlled by the ECU.

The standard toyota igniters have inbuilt dwell control and is not controlled by the ECU.

SprinterTRD - great information you gave, but it would appear these two statements are contradictory, or I just took a double dose of dumb*ss today.

In the 1st statement were you referring to the later COP's which have integral igniters, and the 2nd statement referred to the standalone type igniters (2JZ-GTE)?

John

 

[SprinterTRD]

John,

to clarify,

Toyota COP units dont have inbuilt dwell control & the ECU determines dwell.

The Toyota igniters that have an coil connected like 4AG, 1UZ & 3SG do there own dwell control. The ecu just sends the igniter a pulse.

The ford COP needs a external igniter or ignition module to work but the toyota igniter will apply too much dwell heating the coils up. The ford ECU has inbuilt coil drivers and controls the dwell so if ford COP are going to be used, an aftermarket ECU will need to be used that can control dwell.

 

[cribbj]

Thanks for that; in the Supra camp we were always under the assumption our stock system on the 2JZ-GTE, (six COP's with an external igniter module) had a "smart" igniter that controlled the dwell, rather than the ECU itself. This is as you described in your 2nd sentence.

Our system doesn't work well at all when it's connected in waste spark mode with a standalone ECU, and it requires an external ignition "amplifier" like the HKS Twin Power DLI, or similar to function under higher load & boost than stock.

Would it be reasonable to assume that the latest COP systems, like the VVTi 1UZ, 3UZ, etc. where each coil has a builtin igniter, would have "dumb" igniters that depend on the ECU for dwell control?

If this is true, they should work OK with the standalones like the AEM and others which handle dwell control.

John

 

[SprinterTRD]

John,

I think the problem you have with the 2JZ module is that it is only designed to fire one output at a time. The module has a current limit of around 8-10 amps, by firing 2 outputs you are halving the available current to each coil (say 4Amps each) thus reducing the coils spark energy output.

Sounds like you need a ECU with 6 ignition outputs!

 

[turboandrew]

Current limit could have somthing to do with it. Back then I used an MSD DIS4-HOm which seemd to have no end to the spark energy. I wish the 1UZ COPs did not have an ignitor, as I would just use the MSD again. Perhaps the Ford coils are the way to work, but hopefully I can avoid all that and get the AEM to control the 1UZ COPs directly with some minor modification.

 

[cribbj]

I think the problem you have with the 2JZ module is that it is only designed to fire one output at a time. The module has a current limit of around 8-10 amps, by firing 2 outputs you are halving the available current to each coil (say 4 Amps each) thus reducing the coils spark energy output.

Sounds like you need a ECU with 6 ignition outputs!

I think you're right on both points. Since the igniter dwell limit is factory set for the 2JZ, the only thing that can be done is change out the whole system, which several Supra owners have tried with varying degrees of success, or add yet another box to the system like the HKS, or the MSD as Andrew mentioned.

Any thoughts on whether these later Toyo/Lexus 4 wire COP's with the integral igniters will work directly with an ECU that has dwell control? It would seem they would.

John

p.s. We've been bi*ching to AEM for the last four years that they really shortchanged their system by only providing 5 ignition outputs, but in their minds, with 10 injector and 5 ignition outputs, they've got everything up to a Viper covered. They feel there's no disadvantage to running waste spark, however some of us would strongly disagree with that. All it takes is a misfire on the compression stroke, then the unburnt mixture ignites on the exhaust stroke, and ka-boom!

I witnessed this back in the '80's, offshore, in the Gulf of Mexico, on one of the first waste spark ignitions installed on a 16 cylinder 9390 cubic inch Waukesha engine. The backfire blew the exhaust manifold off the engine, and launched the exhaust system, which was a 42" diameter silencer and around 20 feet of 18" piping, off the side of the platform and into the Gulf of Mexico. Needless to say, the vendors couldn't GIVE AWAY a waste spark ignition for a long time after that.....

 

[turboandrew]

"...launched the exhaust system, which was a 42" diameter silencer and around 20 feet of 18" piping."

ohh crap, you are making the honda boys jealous now!

 

[SprinterTRD]

john,

The Toyota COP with internal igniters will work with ECU's that have dwell control, but all you need to do is add another 2JZ igniter and only use 3 inputs on each module to fire in waste spark mode.

I agree, I dont like using waste spark on high boosted engines, thats where MoTeC have got it right you can use a M4-8 with an MoTeC ignition expander, M600 or M800 all with 6 ignition outputs.

 

[cribbj]

The Toyota COP with internal igniters will work with ECU's that have dwell control, but all you need to do is add another 2JZ igniter and only use 3 inputs on each module to fire in waste spark mode.

Sorry, I've been muddying the thread here, because I was initially talking about the 2JZ-GTE ignition system, and its faults running in waste spark with the AEM and stock igniter.

Then I posed the question about running the later ?UZ COP's with the AEM, however I neglected to mention the application would be on a 1UZ motor, not the 2JZ.

A number of the Supra owners here are in the process of swapping out our 2JZ's and putting in 1UZ's, and I'm sure most, if not all of us will want to run a COP system with a standalone (probably the AEM). Hence the mixed thread.

Back to the point you just made about the 2JZ waste spark application, and about using two igniters and only 3 inputs from each. I would have thought each igniter output circuit would be individually current/dwell limited, and to get around this basic problem, we'd have to wire two igniters in parallel to raise the current to the coils.

With double the current in each output circuit, split between the two coils (parallel coil circuit) everybody ought to be happy. Then it's only whether the coils themselves could handle being charged and discharged twice per engine cycle without overheating & failing.... and I'll bet this would be the weak link.

John

p.s. Autronic, sorry for hijacking your thread!!! I think we're still kinda/sorta on topic though aren't we?

 

[cribbj]

Here's another approach, perhaps convert the six 10 amp channel igniter into a three 20 amp channel box by paralleling the inputs AND outputs and then firing three coils per box as you suggested. The waste spark wiring configuration would then be done at the input to the igniters, as it's done now, instead of at the coils themselves.

What a Frankenstein..... I wonder what this would do to the life expectancy of the coils?

John

 

[username]

Unless everyong already has AEM boxes that need converting, why bother trying to fix something that doesnt work when there are plenty of options that do work straight out? AEM, in my opinion, is nothing particular special. If it doesnt work, or is not flexible enough to run a simple COP v8... move on...

However, if I am mistaken, and the world is saturated with AEMs, and folks dont want to invest in a new box... then, my condulences... keep trying

 

[cribbj]

The AEM isn't a bad box; the 5 ignition outputs are probably its biggest disadvantage, but most of us who use it feel that its advantages outweigh that shortcoming.

When it came out, it filled a void in the standalone market for people who wanted more control than piggybacks could give, but also wanted to retain their OEM sensors and didn't want the hassle of hacking their harnesses and rewiring their cars.

For the Supra PnP application, its connectors allow it to plug directly into the OEM harness, so there's no rewiring required. (BTW, those same connectors are found on the early SC400 harness too.) This is a great advantage when you're facing the alternative - a loom of some 125 to 160 conductors that need to be landed somewhere. With a stock Supra, you can unplug the factory ECU, plug this box in, and have a running (not tuned) car in about 30 minutes.

It has great factory, tuner, and user support and a large population of users in the relatively short time (3.5 - 4 years) it's been out. Plus it's only about half the price of the next tier of standalones that have similar or superior capabilities.

This is not to take anything away from the other boxes, but for a Supra, the AEM is well proven, and of the 3-4 Supra 2JZ->1UZ conversions going on right now in the Lextreme community, I'd guess all of us will probably be using it.

Now if MoTeC or Autronic would come out with a PnP box to fit OEM harnessing, include 6-8 injector and ignition drivers, and price it less than $2500 USD, things would be different.

John