Using Type II Coils Successfully

[DrTurbonicus]

A REAL BRAIN-TEASER & PUZZLER FOR THE HOLIDAYS



Open letter for help to all the wise wiring wizards, all the helpful electrical

gurus, and to all the many natural-born problem-solvers in the TR community:




SCENARIO:


GNTTYPE.ORG posted an article

( http://gnttype.org/techarea/ignition/type2coils.html )

on "how-to upgrade to the Type II

coils" several years ago. GM improved the specs of this system

over the Type I coilpak, & it uses 3 coils, each feeding 2 cylinders.

Clearly, this was an evolutionary step forward, towards the 1 coil

per cylinder systems as used today.



HOWEVER, several in the TR community who have utilized the

comprehensive parts list & instructions as provided on GNTTYPE.ORG

report seeming ignition "break-up" around 5000 rpm. A smaller number

over the past 5 years have posted all went well, but as we know, success

is usually under-reported & vice versa.



As a community, let's examine the "whys" that would explain & correct

the problems, making the swap go well for all. Here's just a very few

sample questions:




QUESTION: What seems to be the indication(s) that the seeming upgrade

to the type II coils does not work well, i.e., what is the nature

of the problems typically encountered post-swap?


PARTIAL ANSWER: Using only the most recent report, ignition "break-up" at

5000 rpm.




QUESTION: Do the issues seem to be arising from problematic components,

*or* some unidentified incompatibility between the type I & II systemsl?


(Note there are millions of the type II coils that

function well in the later model vehicles in which they were used.)



Or, is there an overlooked gremlin, aka human error, in the GNTTYPE.ORG

instructions that could be the culprit? Or is there a need for better

grounding, larger gauge wiring, etc.?




Let's not just write this swap off as "un-doable", or to look for a solution as

"meaningless".


The article was posted on GNTTYPE.ORG to further the

performance of our TRs, & it there is no known reason that it would not

do exactly that.


It's in every hot-rodder's nature to problem-solve & to look at

a pile of parts to see what could be tweaked & improved, so we

should have every expectation this is a simple problem this

collective community can find & fix...together.


Since this is a situation of an electrical nature, let's keep the

discussion **positive**, & not **negative**.



Thanks to each & every boardmember helping, thinking & working on the

**solutions** to this puzzler!

[Steve Wood]

Originally Posted by DrTurbonicus

A REAL BRAIN-TEASER & PUZZLER FOR THE HOLIDAYS



GM improved the specs of this system

over the Type I coilpak, & it uses 3 coils, each feeding 2 cylinders.

Clearly, this was an evolutionary step forward, towards the 1 coil

per cylinder systems as used today.

From where did you draw this info, or conclusion?

[GNVYUS 1]

Bruce will probably chime in here to help you, he has done this but I believe he is using a bunch of Accel coils to help with the spark energy $$$$.

[DrTurbonicus]

Originally Posted by Steve Wood

From where did you draw this info, or conclusion?

Comparing the specs of the available type I coilpaks vs. the available type II

coils shows a small, yet positive increase in its electrical potential(s).


Just as the coilpak was an evolutionary step forward from a single coil firing

all cylinders, the type II coils were the next interim step which eventually

led to the current one coil per cylinder.


Lastly, I respect the credibility & motivation of the fellows posting the Type

II Coil Swap article on GNTTYPE.ORG to have had a positive & helpful intent

towards our shared quest to help our TRs be all they can be,

just as is *the purpose of this thread* is to examine & hopefully solve any

discernible reasons this intended upgrade has encountered the noted

problem(s).

[Steve Wood]

I have never heard that it was supposed to be better....One would have thought that vendors would have jumped on the bandwagon as some did with the "superior coilpack".

It was touted as a cheaper way to go as one only had to replace one, cheap, readily available coil, and, no expensive modules involved.

Improper grounding was supposedly the cause of high rpm break up. It appears that it was another better idea that failed to take off.

Any resemblance to coil over ignition is probably coincidental.

[GNVenom]

My recollections and observations of the TYPE II coil module:

1. There is one less pin for power feed to the module; only one positive 12v feed gets split between MODULE power and COIL power. I believe it's the CCCI fuse that runs to both of them
NOTE: This could explain the "breaking up" at high RPM's. Sharing the feed could potentially cause interference to the module circuit since the power is shared.

2. Because of the fact that we're trying to provide energy for a turbo engine vs. normally aspirated engine, it could be the lack of ignition energy that causes the "breaking up". It has been well established that a boosted engine requires more spark energy than a NA engine. This could explain a few things.

3. The spark energy output is relatively the same with the Type I and Type II coils.

Years ago when I did bench testing, I found the current draw that was observed to be virtually identical between these two systems as I recall. I also found that the stock GN wiring harness lacked sufficient wire gage, resulting in significant voltage drop to the coils, due to excessive overall resistance. I built a "hotwire' system back then to fix this potential problem.

Current day volt boosters have a very positive effect in increasing spark energy to the ignition system. It may be necessary to utilize a volt booster when using a Type II system.

There may be a few other differences but I can't remember <g> good ol' aging. I did a considerable amount of bench testing several years ago.

[DrTurbonicus]

Originally Posted by GNVenom

My recollections and observations of the TYPE II coil module:

1. There is one less pin for power feed to the module; only one positive 12v feed gets split between MODULE power and COIL power. I believe it's the CCCI fuse that runs to both of them

NOTE: This could explain the "breaking up" at high RPM's. Sharing the feed could potentially cause interference to the module circuit since the power is shared.


2. Because of the fact that we're trying to provide energy for a turbo engine vs. normally aspirated engine, it could be the lack of ignition energy that causes the "breaking up". It has been well established that a boosted engine requires more spark energy than a NA engine. This could explain a few things.

3. The spark energy output is relatively the same with the Type I and Type II coils.

Years ago when I did bench testing, I found the current draw that was observed to be virtually identical between these two systems as I recall.

I also found that the stock GN wiring harness lacked sufficient wire gage, resulting in significant voltage drop to the coils, due to excessive overall resistance. I built a "hotwire' system back then to fix this potential problem.

Current day volt boosters have a very positive effect in increasing spark energy to the ignition system.


It may be necessary to utilize a volt booster when using a Type II system.


There may be a few other differences but I can't remember <g> good ol' aging.

Great insights from a master of TR wiring and electronics!

This info adds greatly to the problem-identification & problem-solving process.


Thanks for your continuing thoughts on this, John!





www.casperselectronics.com

[Doc1of7]

The type II coils are the only ones that got used on the S/C later 3800s, that's lead me to believe the energy level is sufficient to work in boosted motors.

There are two different Type II ignition modules, the difference is one has a designated ground. FWIW, that's the only one I use.

In best form the most plug gap I've successfully run with a Type I coil pack, at any serious boost level was .040".

I'm rather fanatical about having enough spark, and fuel....
So,

I started playing with the eDist. With it, I could clip the side electrode of the plug and 18-20 PSI boost. But, installing a plug with an .035" gap, it still took a lot of care plug, and tune wise to run ~26-28 PSI of boost.

So,
Went to the Quick Start Type II igniton set-up. It gets chilly here, and there are times where the car sits for weeks, and the batter gets kinda low. The Quick Start took car of ALL my starting *issues* (thou minor). But, I was back to having to run an .030" gap......

So,
I went to running 3 ACCEL CD modules. One per coil..
Didn't have any ignition problems.
But,
Just for grins kept looking for, and bought 3 more ACCEL CD modules. Then after some more reading, saw where the GM TBI V8 coils were *slow saturation*. So bought 6 of them, and wired them up with the 6 ACCEL ignition boxes. While still firing the coils in a *DIS Mode* (two at a time). While there doesn't seem to be any *major* increase in power, I was able to lessen the AE, and with tuning run 87 Octane. I can also run an AFR down to about 18.5:1, trouble free. Thou, at that mixture the engine is rather lame.

For the StageI engine that will be going in my Stang will have the Quick Start, and 3 ACCEL modules wired to 3 Type II coils.

I don't know the *whys*, but there just seems to be some sort of ignition threshold at 4,500, and 5,000 RPM. You gotta have enough RESERVE Spark energy to reliably fire the plugs at those RPM, under boost.

FWIW, with the 6 coil set-up, the spark is a VERY bright Blue at gaps of 1.25".

With the non CD ignition systems a Volt Blaster, did seem to help, slightly.

With enough spark, you can run less timing.......
*Generally*, for every .005" increse in plug gap, *buys* you about 2d timing.

I have yet to see any *punch through*, which according to Dr Jacobs, is when there is so much spark that it blows across the plug gap with such force that it doesn't properly generate a flame kernel...

[Steve Wood]

Here are a couple of threads that illustrate the problem discussed by John

http://www.turbobuick.com/forums/gen...hlight=type+II

http://www.turbobuick.com/forums/gen...hlight=type+II

[Doc1of7]

Originally Posted by Steve Wood

Here are a couple of threads that illustrate the problem discussed by John

Anyone care to post a quick recap of what was said?.
I'd perfer not to have to check in on that Board.

[Steve Wood]

Pretty much what John stated above. One small wire feeding both the module and the coil pack (as opposed to two)...under load, there is a voltage drop which causes the misfire.

Not enuf power difference between the setups to justify the hassle...going to msd coils, etc. works much better, but, is expensive.

[corsair231]

I've been running the type II set up for about 3 years. I've not had any problem with it at all. I recently went to the track, runnning 17-18 lbs and coming thru the traps @ 5300 with no break-up or spark drop that I could tell. It is a junk-yard set up and I did no additional wiring mods. I pretty much just bolted it in and went. There was not a problem with my type I, except I had a aftermarket stock replacement coil, but I got a great deal on the OEM type II stuff and decided to try it. The only thing I think really changed is that it seemed like my idle did smooth out. I've not had a problem with it's performance so I've left it on. It may be a whole different ballgame if boost or rpm is increased.

[GNVenom]

For those curious about the Type II system, here is some pertinent information. Look at the lower right corner of this page, there are layout details and GM part numbers for the system.

http://www.installationinstructions..../ccci-info.pdf

[DrTurbonicus]

Originally Posted by GNVenom

For those curious about the Type II system, here is some pertinent information. Look at the lower right corner of this page, there are layout details and GM part numbers for the system.

http://www.installationinstructions..../ccci-info.pdf

Thanks for posting the info above, John!