How far can our ignition systems go?

[Zuffen]

There are a few members running big boost whilst there are quite a lot of others run 10lb and under.

Has anyone had trouble with our standard igniters and coils not being up to the job of firing the mix under boost?

Has anyone compared standard and aftermarket ignition components for our engine?

Are COP's better than our igniters, coils and caps?

 

[cribbj]

I think we're in another transition period with ignition systems. For many of us, COP's are a chic solution, but they have their drawbacks too. Due to their compact packaging, they can't deliver as much energy as a CNP (coil near plug) setup.

The pro dragsters, and other people making huge amounts of boost (>25psi) prefer to use CNP's because they need the higher energy levels available with the bigger coils.

Those running huge boost at high RPM's go one step further and use individual CNP's per cylinder to make the most of the short dwell time available at high RPM.

Moderately high boost (15-20psi) can be accommodated by standard COP's, or possibly even the standard distributor ignition on the 1UZ. I wouldn't try to run the standard ignition setup at high boost and high RPM, however.

Being a geeky EE, I prefer COP's because the clunky and lossy dizzies are eliminated, along with the lossy high tension secondary leads, and this gives the motor a much more accurate crank trigger mechanism to fire the coils.

Once the OEM's come up with a COP capable of delivering 100 millijoules with a long life, I think the handwriting will be on the wall for CNP's in OHC applications.

 

[JustenGT8]

On 17psi and 10:1 compression i haven't had any problems out to 7000rpm...oh yeah WI too.

I reckon i'm on the limit though as i have had to close the gap down to 0.8mm. supposedly the small electrode iridium plugs can stretch things further? but have heard mixed reviews so for now will stick with the good old fashioned champion golds

 

[Lextreme II]

As for me, I will most likely to run CNP (Coil Near Plug). I will be following John's advise. From the economic standpoint the price for the conversion from our standard ignition system to COP or CNP is about the same. The Tundra COP is about $95 each unless u can find some used for alot cheaper. CNP coil John found is about $68 each plus a good set of wires. The biggest program I am facing now is find enough space to put 6 additional coils (two will using stock coil location). Each CNP coil is about the same size as the stock.


However, COP still take work too. Currently there is no perfect COP for our engine. I got ONE Tundra COP and did some testing on it, but still require some mods. Now the question I have would be how much power/psi would those Tundra COP can handle? I have talked to few guys with Tundra and they are thinking of upgrading to something else too.

 

[Zuffen]

CNP looks the way to go perfomance wise and really isn't too bad price wise.

I can mount the 8 coils without any problema and run the wires under the stock covers from the rear of the engine.

This will leave me a set of rotors, caps and wires new in their boxes!

I was trawling through Summit Racing the other day and some of the coils look like they would handle almost anything short of a fuel dragster.

Loks like time to talk to my engine and wiring man and see what he want to do.

 

[Lextreme II]

Rod,

Keep us posted with your progress. I am learning the whole ignition thing too.

 

[cribbj]

Rod, the GM LS1 & LS2 coils are a popular CNP setup; they provide a lot of energy and they're dirt cheap. They're not as powerful as that arc welder that David is using, but they should be fine for most big boost applications.

Here's a page from the Megasquirt manual about coils with some good details about the LS1/LS2's: Megasquirt Sequencer Coils

And one from HybridZ that shows some good bench testing of the LS1's

These have built in ignitors as well, so you can easily drive them from your EMS.

 

[Lextreme II]

John,

Do u happen to know what is the stock coil Voltage rating is and 2uzfe Tundra COP? I noticed lots summit coils are 40kV o 60KV. I noticed mines are rated at 60 to 100KV.

Are those LS1 Coil you are talking about? They are listed at around $92 each.

 

[cribbj]

David, no I really haven't paid too much attention to the KV ratings; I try to learn the energy the coils can deliver in millijoules, and what the secondary current and duration of the spark will be.

The reason for this is that I believe KV ratings are a bit misleading - that's just the voltage the coil is capable of, when in reality, it's the size & condition of the spark plug gap, and the conditions the engine is running under that will determine the KV that is actually required to jump the gap.

Generally, the bigger the coil, the more energy it can deliver, so in practical terms, size does make a difference Your coils, for example, can deliver around 100mj of energy with a secondary current of over 400ma and a spark duration of nearly 900 microseconds. That's one impressive spark, and I think it'll ignite nearly any mixture you'll want to run in that twinturbo monster you're building.

Here's an interesting read from Simple Digital Systems. I've always liked this guy's style of writing: http://www.sdsefi.com/techcomb.htm. I think this is good information, but keep in mind he has a vested interest in selling inductive ignition technology.

 

[Zuffen]

Looking at the l;atest Sumit Cattledog they sell a Crane coil for $51.95 that will deliver 100milleamps for 330millesecods. or you could the Jacobs @ $69.95 and have 300milleamps and 220 milleseconds.

8 of them would cost around $560.00. Which I don't think is over the top for bullet proof spark.

 

[Zuffen]

Should have said microseconds there.

Assuming I can run 8 igniton drivers in my chosen ECU it would ensure bulletproof ignition at reasonable cost.

 

[Lextreme II]

Rod,

I might get some LS1 coils, brackets and wires just for some testing.

 

[KDog]

The LS1 coils are a known entity, you will find many pages about their performance and various tests by googling them.

The stock system is quite capable if its in good condition. Because it has many parts its quite rare to have one working 100% (especially on a 1uzfe which could be 18 years old).

If you have a ecu with at least 4 ignition outputs (and dwell control) then the ls1 coils could be a reasonable upgrade compared to repairing a whole stock system.

The good old bosch transformer coil is also a winner but it will require an ignitor if used with the standard inductive system.

 

[Zuffen]

Russell,

As a person who knows their way around igniton systems better than I ever will what would you recommned for a 1UZ'er running more than 15lb boost.

Cost aside.

 

[Lextreme II]

Dear Kdog and Zuffen,

I recently purchased a set of LS7 coils, wires and bracket. I will be using AEM EMS from the Supra MKIV. I have read that the Supra community had problems running the GM coils. Later I found out it was the ECU not setup properly to run CNP. However, I was told that each of GM coil can handle around 125 hp. I think the hardest part would finding a place to mount them. What do u guys think? Any advice will be appreciated.

As COP it is alot easier and nicer then coil. Cribbj is working on multiple COP on the 1uzfe. He is an expert in COP now. I think he has a collection of COPs in his garage.

 

[cribbj]

Cribbj is working on multiple COP on the 1uzfe. He is an expert in COP now. I think he has a collection of COPs in his garage.

Well, that's at least half right David - I'm definitely accumulating quite a collection of COP's and other ignition parts, but I'm no expert at this.....

Currently I have samples of the following:
Audi/VW 1.8TT (w/ignitor) Beru
Camry (no ignitor) Denso
GM & Chrysler 300 (no ignitor) Delco
Honda S2000 (w/ignitor, I think) Denso
Honda CBR motorcycle (no ignitor) Denso
Toyota Echo (w/ignitor) Denso
Toyota Supra (no ignitor) Denso
Toyota Tundra (w/ignitor) Denso

For ignitors, I have the Supra OEM ignitor, a couple of Bosch's, some VB921's and some other non-current limited IGBT's. Along with the Ford EDIS modules.

I also have an assortment of boots, extenders and other paraphernalia that I'm using for mixing & matching to see what fits best on the 1UZ.

If I ever get a DSS, I'll be able to do some good testing of all these. Also need to get some sort of charging circuit cobbled together so I can do some programmable dwell times for these coils.

I'll be interested to hear Russell's response, as I think he's quite a fan of CDI.

 

[KDog]

Zuffen,
If cost isn't a problem then CDI all the way. Full 8 channel
Then 4 channel wasted spark CDI
Then 4 channel, 8 Coils with built in ignitors (inductive)
Then 2 channel stock system in good condition.

Of course a stock system in good order would probably run 15psi. But you may go through leads/coils quickly.


Lex,
Keep the coils/leads away from heat as much as possible. Other that whatever looks good.

 

[Zuffen]

Russell,

I gues my next question is which brands should we look at and which ones should we avoid?

 

[KDog]

There are many good brands out there which can meet your needs, depending on what they are.

Pectel, EFI technology, Motec, Autronic, M & W.

 

[JustenGT8]

So how's this CDI work anyways? I'm currently running the stock ignition on a regular 17psi and now up to 22psi with water/alcohol injection. I have had to close the plug gap down to 0.8mm but apart from that no other issues to date.

Any benefit to be had from running the CDI on the current stock twin coil setup (would it burn out the rotor button?).

I have vvti UZ CoP to use as well as the Honda bikes ones that fit but not sure i want to go to the effort to rewire and reconfig the Autronic SM2?