Auto Racing: coil, whiz kid, coil resistance

Question
QUESTION: This is not about racing but about the "science" behind ignition systems.
Regular auto repair people do not seem to know.

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The short questions:
What happens when a coil resistance between terminal 1 and high tension
terminal is higher than the vehicles specifications?

For that matter - are lower resistance ignition wires a good or bad
thing?

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The long question:

1988 244 DL

I was recently working my way through an Emission Test failure and one thing I did was check the coil.

Coil test - OLD - 0 221 122 345
-across terminals 1 and 15 - 1.1 -1.3 ohm
 (spec. 1.1 -1.3 ohm)
-across terminals 1 and high tension
 (ignition cable) terminal - 12.18 kohm
 (spec. 9.6 -11.6 kohm)

12.18 was high .. out of spec so I ordered a new Bosch replacement.

When I received the new coil I tested it.

Coil test - NEW - 00059
-across terminals 1 and 15 - 1.1 ohm
 (spec. 1.1 -1.3 ohm)
-across terminals 1 and high tension
 (ignition cable) terminal - 13.5 kohm @ 68 F
 (spec. 9.6 -11.6 kohm)

The new coil is even further out of spec??!

I have the correct Bosch Replacement for the orignial Bosch coil.

Bosch has nothing to say about it and the parts supplier reportedly pulled several from the shelf and they are all high.

I'm no electrical engineer so I can only go by the specs. I have enough experience with parts suppliers to have little faith.

What is your understanding of the electrical specifications on a coil and how it relates to the rest of the ignition system?

For that matter - are lower resistance ignition wires a good or bad thing?

Thank you.

ANSWER: OK  please don't give negative feedback for this answer, I'm no electrical whiz kid either.  
MY answer to the first question is when the resistance is TOO high  there will be no spark.  Judge the efficacy of the coil by the fatness and length of the spark. Longer and fatter is better, and bluer is better than yellow.

MY answer to question two is that it depends on how high you value your radio sounds, high resistance wires were first developed to combat ignition noise. Until just recently I used real copper wires in my race cars thinking I was getting the ultimate voltage at the plug that way.
The folks at MSD Ignition recommended a resistance wire and I switched, I noticed no change at all.

The fact that Bosch has nothing to say about the coil specs indicates to me that they don't consider it important, or they don't care. I suspect it's' the former as Bosch has always been a fine , high quality company with excellent products.  
 
Problems with emission tests are WHY I limit myself to race car questions, I don't LIKE it, and I don't want to work on it.  I send that stuff out to a local retail mechanic.

I wish I could offer more help,

Good luck !!

Dan Liddy,

Sarasota, Florida

---------- FOLLOW-UP ----------

QUESTION: Thank you Dan.

I this still begs the question of how high a resistance is too high, or low,  for a particular ignition system? I can accept that the fire at the plug is the ultimate aim. I take it you are pulling the plugs and checking spark to the rocker arm cover ... in the dark (?).

I'm surprised the only thing ignition cables resistance manages is the static on the radio. To my unknowing mind the less drain between battery and spark plug the better ... so good.

I called Bosch and they were going to, and never did, call me back. I had a high opinion of them up to that point.

I did work my way through the emission problem. It was the first time I HAD TO get acquainted with emission controls. Overall they seem to be another system laid over everything else ... and I hate to admit it but it does indicate the health of the engine ... not just the exhaust ... on passenger cars anyway.

Answer
Well I have a gadget you can get at most parts houses, a "spark checker" that hooks to a plug wire and then to ground , with a window through which you can watch the spark, and even adjust the spark length.

As far as how much resistance is too much, I simply don't know. You might try e-mailing Circle Track magazine for more info and EVERYone should subscribe to it. It's dirt cheap at about $15 per year and packed with good solid technical info, how to articles, and all sorts of stuff.  
Even if you're not a stock car fan, it's the best technical rag around, and well worth the little bit of money. You'll find the addresses on Google .

Good luck again
Dan