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HEI Conversion Coil Question

It would be interesting to see how well the hidden GM style ignition module faired out mounted directly to the bulkhead. VERY important that the module has a generous amount of heatsink compound between it and the mounting surface. You might also cut out some of the stock ECU case sides and bottom providing air flow. That module needs to breath or it will fry itself just like it did back in the 1970s.

You would be surprised how HOT the E-Core spark is. I have an adjustable spark gap tester that I hooked into my system after the HEI upgrade. Got a BLUE-WHITE spark jumping over 3/8 of an inch.
Why don't you show us some voltage (in terms of kilovolts or 1000's of volts) vs a measuresd dimension. Show us some pix of your adjustable spark gap tester....like brand name, test conditions. The comment: "got a blue-white spark over 3/8" means nothing....it's like saying a little pregnant....the spark is in air...not in the interior of the engine, at temperature and under compression, given a milli second of time to ignite the mixture....at 5000 RPM. The secondary voltage produced by the coil is determined by the primary to secondary volts per turn ratio. The argument that the conventional design vs the E core design is moot.....it's just the E core design is different appearing, therefore to some (the uneducated) is better...just because it's different, ....both, the are windings are of the autotransformer designs....one is oil insulated vs epoxy insulated....but the method the secondary voltage developed is identical...by magnetic induction........just my opinion of course......
BOB RENTON
 
Rich Ehrenberg is often quoted when discussing matters related to Mopars.
I agree with many of his opinions but not every one of them. Like many engineers, he often forms opinions based on math that looks great on paper and in theory but sometimes falls short in the real world.
One of those times was his refusal to believe that the taller FMJR front disc steering knuckle was an adequate unit for disc brake swaps. His contention was that the taller knuckle would lead to upper ball joint failure.
One thing he also is stuck on is the opinion that There is no power in ignition.
I'll admit, I don't know nearly as much as he does about this stuff but just using basic common sense, how can his opinion be true?
It seems like a spark with greater energy would make for a more complete combustion event. Is it a matter that once the fire is lit, the cycle is already in effect? Is his opinion based on the theory that any spark great enough to ignite the air-fuel mixture is adequate?
 
Bob,
The only person who is uneducated about the efficiency difference between a canister coil & an E core coil............is YOU. Find some PROOF & post it that claims that a canister coil produces a hotter spark.
The heat in the spark is what ignites the A/F mixture. That heat comes from secondary coil current.

The MSD Blaster 2 & 3 canister coils have a 140mA peak current.
The MSD Blaster 8207 E core coil has 300mA.
The high power MSD E core coils have sec currents ranging from 600 mA to...2 amps.
 
One thing he also is stuck on is the opinion that There is no power in ignition.
no EXTRA power from expensive or fancy stuff.
. Is it a matter that once the fire is lit, the cycle is already in effect? Is his opinion based on the theory that any spark great enough to ignite the air-fuel mixture is adequate?
yes an adequate spark is adequate. It's not a theory. Just reality.
 
Many of us claim to know this or that that is taking place inside the combustion chamber, quite frankly I doubt many of us really know any more than the seat of our pants tells us. Even fewer of us know why one coil, ignition module, spark plug, plug wires, etc. over another really works better than another. There are some here in this forum and even in this thread that will swear Mother Mopar never has done anything wrong ever and could never be improved upon. I get the same crap from some of my Chevy and Ford friends. My feeling is, it is your car, do whatever you want to do to it to make it more dependable, more powerful, more efficient, more sexy. Personally, Mopar runs deep in DNA from my teenage years, but it's not because it couldn't be improved upon. Hence the reason for this thread and others like it. Common sense tells us that spark, spark timing, octane level, compression, ability for the engine to inhale and exhale properly all play a part in our engines running to it's maximum levels in the combustion process to one degree or another. Personally, I put more stock in someone who has actually tried this or that and speaks from real time experience and can advise concerning the pitfalls or benefits firsthand.
 
Anybody who thinks a spark is just a spark is living in la-la land.....
I have read about this....& to me it is logical & very likely true.
The MSD Multi Fire CD igns such as 6X were developed by Autronics in conjunction with Chrys. With the Nascar hemis were getting faster & faster [ more rpm ], they were running out of spark.
During testing, the MSD unit was found be misfiring at low rpms, where a long duration, hot spark is needed. The fix was 'multi spark' at low rpms. Some bright spark [ pardon the pun ] at Autronics in marketing turned an engineering failure into a winner by clever marketing!! The reason the CD ign was failing at low rpm was that although the CD spark is very powreful, it has about 1/10th the duration of an inductive spark. CD is great for 2 strokes that foul plugs because there is literally not enough time to bleed off the spark.
 
Go with what Ray/ @HALLIFAXHOPS recommends...it resembles an OEM design yet is compatible with the HEI module and purchase a E Coil and compare. Bear in mind, that there is NO 50+ hp increase in either system in spite of what your buddies may think....BOB RENTON
HEI doesn’t add power, it just prevents power loss
 
HEI sure does add power [ to the spark ]. How many ign systems do you know that can run 0.080" plug gaps?

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Yeah, we get it...HEI makes a hotter spark BUT does that help if the spark you already have has already ignited the mixture?
Chrysler didn't think so. If the spark is adequate enough to start combustion, the flame takes on a life of it's own then, right? No amount of increased energy at the spark plug will make a better combustion event. The stock electronic ignition runs below battery voltage, right? HEI was designed for emission reduction anyway, not power increases.
Ehrenberg argued that unless you're running some manner of boost or other power adder, there is no power in ignition. If you aren't misfiring, there is nothing to be gained. Ehrenberg even stated that all those gimmicky multi pronged spark plugs offered no improvement. The fine wire and iridium plugs were considered better though because their heat ranges were wider and that they should be able to work longer without fouling. That claim holds true since OEMs have touted 100,000 mile spark plug change intervals for some engines.
 
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And that is the POINT. Misfiring. If the spark misfires, there is no second chance. So you make sure that the first [ & only spark ] is realllllllllllllly hot, overkill, if you like.
What do you think causes the rough idle with a hot cam? It is the engine misfiring. If somebody developed a super-hot ign system, that rough idle might be cured....
 
Screw that. The lope of incomplete combustion is intoxicating.
 
I will leave you this info. Many people claim that a spark plug......is a spark plug. Nothing to see here.....
Well, not always.......
This maybe an extreme example....but it is still an example.

img109.jpg
 
Just adding something to consider regarding "any spark is adequate". Most piston aircraft engines have two complete and separate ignition systems for redundancy. During your preflight check, you turn off one at a time to confirm they are both working. The RPM will drop 10% or so when only one plug fires instead of both. Same when under power during flight. Two relatively weak sparks proven to be more efficient than just one.
And they definitely run better when one of the antique yet reliable magneto systems is replaced with an electronic higher output setup, albeit the timing curve has a lot to do with the improved performance.
 
Just adding something to consider regarding "any spark is adequate". Most piston aircraft engines have two complete and separate ignition systems for redundancy. During your preflight check, you turn off one at a time to confirm they are both working. The RPM will drop 10% or so when only one plug fires instead of both. Same when under power during flight. Two relatively weak sparks proven to be more efficient than just one.
And they definitely run better when one of the antique yet reliable magneto systems is replaced with an electronic higher output setup, albeit the timing curve has a lot to do with the improved performance.
Edzacery...
20241021_175749.jpg
 
Lookie what Davis Unified Ignition came up with....

1730706763509.png


That sure looks like a GM HEI module they have mounted on the side....
 
That’s exactly what they did
Does it work any better?......I guess the volts fallout faster..... Therefore it must work better.....50+ additional hp awaits the user....a new fad...why not be the first in your group to use this setup.....that's what my next doors neighbor's uncle's brother in law said so because 20 years ago he worked for a Yugo dealership washing cars...and authoritative source of information...to be sure.....
BOB RENTON
 
It has one review from years ago that says it won't fit his engine as the module is in the way. It also doesn't include the coil. It cost me less than $100 to convert my Mopar electronic dizzy to use the HEI module and buy a coil to go with it. Plus it fits in the engine.
 
It has one review from years ago that says it won't fit his engine as the module is in the way. It also doesn't include the coil. It cost me less than $100 to convert my Mopar electronic dizzy to use the HEI module and buy a coil to go with it. Plus it fits in the engine.
What's a "DIZZY"??......just must be some emission control device or part of a diesel engine ?? Whereas points DISTRIBUTOR ignition systems are designed to fit the engine. Is a dizzy similar to a carby or oil pumpey or a crankshaftee ?? Just curious.....
BOB RENTON
 
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