Home » Public Forums » GMCnet » HEI vs Petronix (Ignition)
| HEI vs Petronix [message #351793] |
Thu, 30 January 2020 15:20  |
thigh19
Messages: 92
Registered: July 2019
Location: Vancouver Wa
Karma: 1
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My 73 Sequoia still uses points. Most I've seen out here is HEI. I use petronix on my 68 Rambler gasser to keep the old school look. I've used petronix on multiple occasions and am happy. I know HEI is about as simple as you can get. If I go HEI, I know I'll have to change air cleaner, but not much else. Cost is a coin toss, with eBay , both under $100. Any thoughts from you guys?
Thanx in advance
Thom
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| Re: HEI vs Petronix [message #351794 is a reply to message #351793] |
Thu, 30 January 2020 16:30  |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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both have good and poor points, but for every Petronix ever made, GM made a hundred or more HEIs over the years. Use the correct grease on the module, be sure all the connections are tight, and it should outlast the engine. Belt and suspenders- carry a spare module, they're cheap and small to hide. I've seen more cap failures than module failures, and some cap failures can lead to module failures.
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
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| Re: HEI vs Petronix [message #351795 is a reply to message #351793] |
Thu, 30 January 2020 17:59 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
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The Pertronics that reads the lobe bumps is super easy to install. I put one in a big block Buick and noticed smoother idle. I put the points snd condenser in the glove box in case the unit gets stupid. I did not upgrade the coil or remove the resistor wire. So triggering is more accurate but probably no more spark energy available. My coach is HEI and I have never had a failure, but I replace wear items before things go bad. With HEI there is more energy to do damage or self destruct when the correct path to ground gets dodgy.
John Lebetski
Woodstock, IL
77 Eleganza II
[Updated on: Thu, 30 January 2020 18:00] Report message to a moderator |
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| Re: [GMCnet] HEI vs Petronix [message #351796 is a reply to message #351795] |
Thu, 30 January 2020 19:22 |
jimk
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
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Pertronix with the lobe sensor is more relatable than a newer HEI, as the
module and coil on them has been a source or ignition issue. You can
thank the RED Chinese for that.
On Thu, Jan 30, 2020 at 4:00 PM John R. Lebetski via Gmclist <
gmclist@list.gmcnet.org> wrote:
> The Pertronics that reads the lobe bumps is super easy to install. I put
> one in a big block Buick and noticed smoother idle. I put the points snd
> condenser in the glove box in case the unit gets stupid. I did not upgrade
> the coil or remove the resistor wire. So triggering is more accurate but
> probably more spark energy available. My coach is HEI and I have never had
> a failure, but I replace wear items before things go bad. With HEI there
> is more energy to do damage or self destruct when the correct path to
> ground gets dodgy.
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmcrvparts.com
1-800-752-7502
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Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
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| Re: [GMCnet] HEI vs Petronix [message #351797 is a reply to message #351796] |
Thu, 30 January 2020 21:20 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
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Anything that uses a phenolic rubbing block that runs against a cam lobe
will NOT be much more reliable when it comes to precise timing than contact
points are. Stuff wears out when run next to cam lobes with minimal
lubrication.
HEI, on the other hand relies upon magnetic pole reversal to trigger
the ignition, and there is no parts rubbing against each other. Set it,
gap your plugs to .045" or so and forgetaboutit.
What Jim K said about OFFSHORE parts unfortunately, is substantially
correct. Sad day, that.
Jim Hupy
Salem, Oregon
On Thu, Jan 30, 2020, 5:22 PM Jim Kanomata via Gmclist <
gmclist@list.gmcnet.org> wrote:
> Pertronix with the lobe sensor is more relatable than a newer HEI, as the
> module and coil on them has been a source or ignition issue. You can
> thank the RED Chinese for that.
>
> On Thu, Jan 30, 2020 at 4:00 PM John R. Lebetski via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> The Pertronics that reads the lobe bumps is super easy to install. I put
>> one in a big block Buick and noticed smoother idle. I put the points snd
>> condenser in the glove box in case the unit gets stupid. I did not
> upgrade
>> the coil or remove the resistor wire. So triggering is more accurate but
>> probably more spark energy available. My coach is HEI and I have never
> had
>> a failure, but I replace wear items before things go bad. With HEI there
>> is more energy to do damage or self destruct when the correct path to
>> ground gets dodgy.
>> --
>> John Lebetski
>> Woodstock, IL
>> 77 Eleganza II
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk@appliedairfilters.com
> http://www.appliedgmcrvparts.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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| Re: [GMCnet] HEI vs Petronix [message #351799 is a reply to message #351797] |
Thu, 30 January 2020 22:04 |
jimk
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
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Senior Member |
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Pertronic unit uses a magnetic pulse off the existing lobe, so there is no
wear involve.
We supply those units to Dick Patterson of Springfield Ignition.
I know we can provide them at same prices , tru us.
On Thu, Jan 30, 2020 at 7:16 PM James Hupy via Gmclist <
gmclist@list.gmcnet.org> wrote:
> Anything that uses a phenolic rubbing block that runs against a cam lobe
> will NOT be much more reliable when it comes to precise timing than contact
> points are. Stuff wears out when run next to cam lobes with minimal
> lubrication.
> HEI, on the other hand relies upon magnetic pole reversal to trigger
> the ignition, and there is no parts rubbing against each other. Set it,
> gap your plugs to .045" or so and forgetaboutit.
> What Jim K said about OFFSHORE parts unfortunately, is substantially
> correct. Sad day, that.
> Jim Hupy
> Salem, Oregon
>
> On Thu, Jan 30, 2020, 5:22 PM Jim Kanomata via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> Pertronix with the lobe sensor is more relatable than a newer HEI, as the
>> module and coil on them has been a source or ignition issue. You can
>> thank the RED Chinese for that.
>>
>> On Thu, Jan 30, 2020 at 4:00 PM John R. Lebetski via Gmclist > gmclist@list.gmcnet.org> wrote:
>>
>>> The Pertronics that reads the lobe bumps is super easy to install. I
> put
>>> one in a big block Buick and noticed smoother idle. I put the points
> snd
>>> condenser in the glove box in case the unit gets stupid. I did not
>> upgrade
>>> the coil or remove the resistor wire. So triggering is more accurate
> but
>>> probably more spark energy available. My coach is HEI and I have never
>> had
>>> a failure, but I replace wear items before things go bad. With HEI
> there
>>> is more energy to do damage or self destruct when the correct path to
>>> ground gets dodgy.
>>> --
>>> John Lebetski
>>> Woodstock, IL
>>> 77 Eleganza II
>>>
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>>
>>
>> --
>> Jim Kanomata
>> Applied/GMC, Newark,CA
>> jimk@appliedairfilters.com
>> http://www.appliedgmcrvparts.com
>> 1-800-752-7502
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmcrvparts.com
1-800-752-7502
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
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| Re: HEI vs Petronix [message #351802 is a reply to message #351793] |
Fri, 31 January 2020 07:48 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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Senior Member |
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JimK, given the production numbers and the amount of design behind both, I can't agree. I would, however, use the American made GM module and coil. I note however, the very few HEIs I've seen fail were due to other problems, -lack of cooling or failure in the high tension system which made a better path than the spark plug to ground... and trashed the module because of it.
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
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| Re: HEI vs Petronix [message #351803 is a reply to message #351793] |
Fri, 31 January 2020 07:56 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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Senior Member |
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Now, as to American vs heathen chinee semiconductors, there seems to be a hell of a difference. One line of Harris AM transmitters used a particular device in the RF modules. The American maker ceased production and the chinese continued at a substantially lower cost. The chinese article would test in every way identical to the American product but showed an unacceptable failure rate in service. One Engineer finally cut a couple of them open, and found that the die in the chinese product was a third smaller than the American, and the connections were half the size. In AM service, where the current in the device fluctuated greatly and was quite high at times, the chinese devices melted. Consequently, NOS parts are now at a premium, and one repair shop is offering a mod to use an available and more robust device.
When the American made modules are no longer available, someone caqn make some change by offering a reliable substitute.
--johnny
n.b. for those radio pigs, I refer to the Tinwork's SX series of AM transmitters.
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
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| Re: HEI vs Petronix [message #351804 is a reply to message #351793] |
Fri, 31 January 2020 08:05 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
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Senior Member |
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James H, with HEI the only think you can forget about is the points, the trigger source. The cap and rotor, wires and plugs are under more stress and things go had in a hurry when they fail as there is more voltage rise possible to "eat" things. The old carbon wires went away in 75 to be replaced with much longer lasting spiral core, but they still have a service life. As plugs age and gap widens the path to ground requires more voltage to jump so the coil Secondary rise increases to make that happen. This also increases the coil primary back voltage. At some point the module can't take the back voltage and that kills it. When I first bought a used Tahoe and had not gone through everything (ran great) it just died in an intersection in the rain. Crank no start at all. I had it towed home to look it over. The inspection showed the coil wire (divorced coil HEI) had vaporized at the cap. Just a nub end no connection or terminal. The HEI systems are a bit like our old GM starters- they work too well until they are way past where they should be working, so you get little warning. (I stole the starter quote from Matt).
John Lebetski
Woodstock, IL
77 Eleganza II
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| Re: HEI vs Petronix [message #351805 is a reply to message #351793] |
Fri, 31 January 2020 09:11 |
Larry
Messages: 2875
Registered: January 2004
Location: Menomonie, WI
Karma: 10
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Back to the point... the points type distributor I have for my 73 Cad 500 needed rebuilding. So I sent it to Dick Paterson. He replaced the points system with the Pertronix 1181 and recurve the distributor. That was in 2005. Last summer, while doing some work on the FI that I have, it suddenly refused to start. After some diagnosis, finally found it had no spark. The 1181 has a pick-up and a ring of magnets that go under the rotor. One magnet dislodged and in turn scrubbed the electronic eye until I had a total ignition failure--complete with coil boiled out. Called and talked with Dick and he said that they had problems with the 1181 Magnet ring, that I should order the 1181LS (LS is for Lobe Sensing), which does not have Magnet ring. I ordered the "Flamethrower" 40011 as the matching coil. Got them from Summit. They had the lowest price and quickest shipping. (next day) Works fine...no moving parts accept the lobes. With the 1181LS you take the points and condenser out, and drop the 1181LS pick-up in it's place. Takes about 5 minutes. Very easy install. Most GM points type distributors use common parts, so the 1181LS should work in your Olds distributor. JWID
Larry 
78 Royale w/500 Caddy
Menomonie, WI.
[Updated on: Fri, 31 January 2020 09:24] Report message to a moderator |
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| Re: HEI vs Petronix [message #351806 is a reply to message #351805] |
Fri, 31 January 2020 10:36 |
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Matt Colie
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
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Senior Member |
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I come down on the Pertronix 1181LS side. If you want more spark energy. Link it to some type of real CDI (Capacitive Discharge Ignition) box. There are still more than a few out there.
I am afraid that I saw lots of HEI failures while doing durability for several GM lines. These were all OE parts, but they still were very failure prone and I got to write the report after our electronics people had finished their analysis of the failed parts. Most failed modules but a few failed the coil. We were running small blocks for Central Foundry when the "too wide gap" problem was identified. We were instructed to shut down all the tests (about 8 then in progress) and hammer the plugs back down to .035. That greatly improved the life on the driving cycle test engines. They were happy about that. There were still still issues with the power peak durability engines. These were engines that also ran a speed/load cycle, but the two running points were the torque peak and the horsepower peak. They sent us new distributors for those, and we were to install and run and return if failed. Few did, but as we did not do the final analysis, I cannot tell you now they failed. The available spark plugs then were still not as good as what we can get today and the high load engines would still burn the gap open in about 100 hours, but that was OK because the heads were shot then too. (Exhaust valve seat recession.)
For those that don't know, it takes more juice to fire the plug at higher cylinder pressures. Larger plug gaps also take more. So, you can guess where we are in a TZE on the highway and when climbing a grade is that much worse.
Now, why did GM care?
Because wider gaps and more spark energy makes for fewer misfires and that makes for both better emissions (they were grasping for plastic straws that this time) and better fuel economy (that was soon to go ballistic too). There were also issues coming with CARB requiring that the engine tuning be a part of the warranty for the first 50k. (Chrysler had beat them to this one.) So, they got to keep the spark energy, but had to relinquish the gap.
There is one big drawback with a Pertonix/CDI system. If you employ a full ECU/EFI system and want to take advantage of timing control, you have to go to HEI for that. That is the only reason I would got to the trouble and expense for that update.
So, what is Matt doing??
Matt has had Chaumière equipped with an 1181LS since her first real season. At first that was connected to a bottom of the line MDS box. The plugs were set to 0.060 and attached by 8.8 wires. I do not remember the number of the MSD box, but it is in a junk bin in my shop. The MSD box failed on the road. Fortunately, all I had to do was remove it from the system for the less than 100 miles to get home. I did close the plugs a little for the trip home. First replacement for the MSD was an antique Delta MarkX. That was an old buffalo had, and it worried me. I scored a MKXb off Ebay and that has been in there for the last decade. I changed out the plugs when I did the overhaul because #7 piston shed its rings a while back.
If someone has a question I did not answer, please come back. I am sure I missed something I should have explained.
Matt - the Dynoland refugee
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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| Re: [GMCnet] HEI vs Petronix [message #351807 is a reply to message #351806] |
Fri, 31 January 2020 12:16 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
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Senior Member |
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Being older than dirt, like me, has a few advantages. I grew up in an era
where there were still some magneto ignitions in use, and for the most
part, 6 volt breaker points type ignitions were in common usage. They
worked O.K. on low compression engines of the 20's, 30's, 40's, and the
very first part of the 50's. Then came the overhead valve Oldsmobile Rocket
V-8's, and Cadillac, and Chrysler Hemi's. All with the unheard of
compression ratios. Those old 6 volt ignitions worked very hard to fire
against that pressure. So, Detroit doubled the voltage to 12 volts. Still,
they used points, and left over 6 volt coils with resistors, as well as 12
volt generators. Remember, the transistor had not been invented yet.
More to come later. Got to run some errands.
Jim Hupy
Salem, Oregon
On Fri, Jan 31, 2020, 8:37 AM Matt Colie via Gmclist <
gmclist@list.gmcnet.org> wrote:
> I come down on the Pertronix 1181LS side. If you want more spark energy.
> Link it to some type of real CDI (Capacitive Discharge Ignition) box.
> There are still more than a few out there.
>
> I am afraid that I saw lots of HEI failures while doing durability for
> several GM lines. These were all OE parts, but they still were very failure
> prone and I got to write the report after our electronics people had
> finished their analysis of the failed parts. Most failed modules but a few
> failed the coil. We were running small blocks for Central Foundry when
> the "too wide gap" problem was identified. We were instructed to shut down
> all the tests (about 8 then in progress) and hammer the plugs back down to
> .035. That greatly improved the life on the driving cycle test engines.
> They were happy about that. There were still still issues with the power
> peak durability engines. These were engines that also ran a speed/load
> cycle, but the two running points were the torque peak and the horsepower
> peak. They sent us new distributors for those, and we were to install and
> run and return if failed. Few did, but as we did not do the final
> analysis, I cannot tell you now they failed. The available spark plugs
> then were
> still not as good as what we can get today and the high load engines would
> still burn the gap open in about 100 hours, but that was OK because the
> heads were shot then too. (Exhaust valve seat recession.)
>
> For those that don't know, it takes more juice to fire the plug at higher
> cylinder pressures. Larger plug gaps also take more. So, you can guess
> where we are in a TZE on the highway and when climbing a grade is that
> much worse.
>
> Now, why did GM care?
> Because wider gaps and more spark energy makes for fewer misfires and that
> makes for both better emissions (they were grasping for plastic straws that
> this time) and better fuel economy (that was soon to go ballistic too).
> There were also issues coming with CARB requiring that the engine tuning be
> a
> part of the warranty for the first 50k. (Chrysler had beat them to this
> one.) So, they got to keep the spark energy, but had to relinquish the
> gap.
>
>
> There is one big drawback with a Pertonix/CDI system. If you employ a
> full ECU/EFI system and want to take advantage of timing control, you have
> to
> go to HEI for that. That is the only reason I would got to the trouble
> and expense for that update.
>
> So, what is Matt doing??
> Matt has had Chaumière equipped with an 1181LS since her first real
> season. At first that was connected to a bottom of the line MDS box. The
> plugs
> were set to 0.060 and attached by 8.8 wires. I do not remember the number
> of the MSD box, but it is in a junk bin in my shop. The MSD box failed on
> the road. Fortunately, all I had to do was remove it from the system for
> the less than 100 miles to get home. I did close the plugs a little for the
> trip home. First replacement for the MSD was an antique Delta MarkX.
> That was an old buffalo had, and it worried me. I scored a MKXb off Ebay
> and
> that has been in there for the last decade. I changed out the plugs when
> I did the overhaul because #7 piston shed its rings a while back.
>
> If someone has a question I did not answer, please come back. I am sure I
> missed something I should have explained.
>
> Matt - the Dynoland refugee
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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| Re: [GMCnet] HEI vs Petronix [message #351808 is a reply to message #351806] |
Fri, 31 January 2020 12:57 |
powwerjon
Messages: 849
Registered: March 2013
Karma: -2
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Senior Member |
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I don't necessary with some comments here. Over the last 20 years that I
have owned our GMC coaches, the first being a 77 with a 403 and the present
being a Buskirk stretch chassis #5 with a 1997 461 Jasper motor, I have had
a number of ignition failures over the years. Primarily the ignition
module and sometimes the coil. All parts that failed were either GM AC
Delco US made or GM AC Delco made in Mexico. Reduced the module failure
rate by reducing the plug gap to 38-40 thousand. The coil failures were
occasional and the coils burnt up and sometimes had a crack and one is
still out in a field outside of OK city where I threw it. The coils appear
to have failed because of the poor cooling of the dizzy located behind the
air cleaner and out of the air flow. Some have added ducted air flow
blowing on the dizzy with varied results. i went to a MSD remote coil setup
in 2013 and have not had any failure of any ignition part since.
This is the parts that I used:
https://www.jegs.com/i/MSD-Ignition/121/8200MSD/10002/-1
https://www.jegs.com/i/MSD-Ignition/121/8401MSD/10002/-1
There is also a short jumper between the coil and dizzy that I can't find
the part number
There is also a photo album on a homebrew remote cap album:
http://www.gmcmhphotos.com/photos/remote-ignition-coil/p50729-home-brew-remote-coil-distributor-cap.html
regards
J.R. Wright
GMC Great Laker
GMCGL Tech Editor
GMC Eastern States
GMCMHI
TZE Zone Restorations
78 Buskirk Custom 29.5' Stretch
75 Avion (Under going Frame up Restoration)
On Fri, Jan 31, 2020 at 9:37 AM Matt Colie via Gmclist <
gmclist@list.gmcnet.org> wrote:
> I come down on the Pertronix 1181LS side. If you want more spark energy.
> Link it to some type of real CDI (Capacitive Discharge Ignition) box.
> There are still more than a few out there.
>
> I am afraid that I saw lots of HEI failures while doing durability for
> several GM lines. These were all OE parts, but they still were very failure
> prone and I got to write the report after our electronics people had
> finished their analysis of the failed parts. Most failed modules but a few
> failed the coil. We were running small blocks for Central Foundry when
> the "too wide gap" problem was identified. We were instructed to shut down
> all the tests (about 8 then in progress) and hammer the plugs back down to
> .035. That greatly improved the life on the driving cycle test engines.
> They were happy about that. There were still still issues with the power
> peak durability engines. These were engines that also ran a speed/load
> cycle, but the two running points were the torque peak and the horsepower
> peak. They sent us new distributors for those, and we were to install and
> run and return if failed. Few did, but as we did not do the final
> analysis, I cannot tell you now they failed. The available spark plugs
> then were
> still not as good as what we can get today and the high load engines would
> still burn the gap open in about 100 hours, but that was OK because the
> heads were shot then too. (Exhaust valve seat recession.)
>
> For those that don't know, it takes more juice to fire the plug at higher
> cylinder pressures. Larger plug gaps also take more. So, you can guess
> where we are in a TZE on the highway and when climbing a grade is that
> much worse.
>
> Now, why did GM care?
> Because wider gaps and more spark energy makes for fewer misfires and that
> makes for both better emissions (they were grasping for plastic straws that
> this time) and better fuel economy (that was soon to go ballistic too).
> There were also issues coming with CARB requiring that the engine tuning be
> a
> part of the warranty for the first 50k. (Chrysler had beat them to this
> one.) So, they got to keep the spark energy, but had to relinquish the
> gap.
>
>
> There is one big drawback with a Pertonix/CDI system. If you employ a
> full ECU/EFI system and want to take advantage of timing control, you have
> to
> go to HEI for that. That is the only reason I would got to the trouble
> and expense for that update.
>
> So, what is Matt doing??
> Matt has had Chaumière equipped with an 1181LS since her first real
> season. At first that was connected to a bottom of the line MDS box. The
> plugs
> were set to 0.060 and attached by 8.8 wires. I do not remember the number
> of the MSD box, but it is in a junk bin in my shop. The MSD box failed on
> the road. Fortunately, all I had to do was remove it from the system for
> the less than 100 miles to get home. I did close the plugs a little for the
> trip home. First replacement for the MSD was an antique Delta MarkX.
> That was an old buffalo had, and it worried me. I scored a MKXb off Ebay
> and
> that has been in there for the last decade. I changed out the plugs when
> I did the overhaul because #7 piston shed its rings a while back.
>
> If someone has a question I did not answer, please come back. I am sure I
> missed something I should have explained.
>
> Matt - the Dynoland refugee
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
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>
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| Re: HEI vs Petronix [message #351809 is a reply to message #351793] |
Fri, 31 January 2020 14:16 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
|
Senior Member |
|
|
Actually, my fave is the 70s Mpoar setup. The only failures I have seen with them is a) the dual ballast resistor and B) poor grounding of the module. The resistor is an easy fix, Ohmite is Your Friend. The second time rust got under the mounting bolts in my 340 car, I took the Dremel and ground down to bare metal on the module and the inner fender and used my old American Beauty iron to solder a braid between them. Never had a problem with it after that, and while we built it back to go, the C/R wasn't really stupid - 10.5:1 I put copper plug wires which wiped out every AM radio for half a mile. When I was driving it sensibly it used a graphite coil wire which shut the noise up. Playing Stoplight Choose-Off, it got the solid one back, and devil take the radio.
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
|
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| Re: [GMCnet] HEI vs Petronix [message #351812 is a reply to message #351809] |
Fri, 31 January 2020 15:21 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
|
Senior Member |
|
|
Back from my first round of errands. So, as electrical loads increased in
automobiles, shortcomings in electricity producing devices did not keep
pace with demand. Permanent magnets were only so strong, so their
electrical fields were limited. No field strength means no high amperage
output. Commutators would wear carbon brushes out quickly, and required
frequent maintenance to remain in top form.
Soooooo, along came inside out generators, they rotated the magnetic
fields (called rotors), and took current off a stationary winding called a
stator. Several incarnations were developed, but a wye (Y) configuration
pretty much became the standard. 1 end of each winding (there were 3) were
joined together, and each other ends were attached to a separate diode.
(Diode trio) 120 ° out of phase with each other. Regulation is a simple
matter of turning the field off and on, thereby limiting field strength and
thusly ALTERNATOR OUTPUT. The GM design pretty much rules the roost.
During this time the solid state devices (transistors, thermistor,
solid state diodes, etc.) took giant leaps forward. Integrated circuits,
etc. became commonplace. Uses varied from microwave ovens to spacecraft.
Cellular telephones, home computers, etc.
I will follow up more later. File length limits.
Jim Hupy
Salem, Oregon
On Fri, Jan 31, 2020, 12:16 PM Johnny Bridges via Gmclist <
gmclist@list.gmcnet.org> wrote:
> Actually, my fave is the 70s Mpoar setup. The only failures I have seen
> with them is a) the dual ballast resistor and B) poor grounding of the
> module. The resistor is an easy fix, Ohmite is Your Friend. The second
> time rust got under the mounting bolts in my 340 car, I took the Dremel and
> ground down to bare metal on the module and the inner fender and used my
> old American Beauty iron to solder a braid between them. Never had a
> problem
> with it after that, and while we built it back to go, the C/R wasn't
> really stupid - 10.5:1 I put copper plug wires which wiped out every AM
> radio for
> half a mile. When I was driving it sensibly it used a graphite coil wire
> which shut the noise up. Playing Stoplight Choose-Off, it got the solid one
> back, and devil take the radio.
>
> --johnny
> --
> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> I forgive them all, save those who hurt the dogs. They must answer to me
> in hell
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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| Re: [GMCnet] HEI vs Petronix [message #351825 is a reply to message #351812] |
Sat, 01 February 2020 13:09 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
|
Senior Member |
|
|
3. Ran out of day before I finished yesterday. Happens more often, these
days. So, after the silicon chip revolution subsided a bit, we found
ourselves smack dab in the 70's. Detroit didn't know whether to keep on
with building MUSCLE CARS, or pay attention to the gasoline shortage?/Oil
embargo that 1973 brought, and make more anemic vehicles like the Vega or
Monza, or K cars etc. But, VW rabbit sales made them sit up and say
"HOWDY".
So, EMISSIONS reared it's ugly head, and they got caught up in making
their products compliant.
SMACK DAB IN THE MIDST of this came development of High Energy
Ignitions. The big three all had their versions, and GM had their share of
learning experiences. After a bunch of transistor ignitions were developed,
and were fraught with failures, GM bit the big bullet, and spent the money
to develop something that filled their needs. Had to last at 50,000 miles
without service. Ignition points needed service every 10,000 miles. So GM
engineers used 100,000 miles as their target. That was TEN TIMES as long
as points. Quite a lofty goal. But, they prevailed with their HEI. The
moving parts are limited to a gear driven distributor shaft with a rotor to
distribute spark around the circumference of the cap. The mechanical
advance mechanism consists of flyweights and springs, like points
ignitions, and the vacuum advance/retard mechanism is also similar to the
ones used with points. Triggering of the primary circuit is by hall effect.
Primary voltage is no longer limited by how much current the points will
stand before they burn up. The higher the primary voltage, the higher the
secondary voltage can be.
I used an Allen Smartscope for tune-up, and HEI will easily drive the
trace off the screen that has a 60 kv range. Yes, it will easily jump a
1/2" gap, or bite you through a pair of Snap-On plug wire pliers. You won't
hold on to it long, I gur-an-tee you.
In mid-year 1975 GMC started fitting the HEI to their Olds 455
engines, and when the 403 engine was introduced in mid-year 1977 it was
fitted on those as well.
I have a 1978 GMC ROYALE with a 403, and it has over 130,000 miles. On the
original HEI distributor. Cap and wires have been replaced in nearly 40
years of service, and I neglected the spark plug gaps, let them open up too
far, and smoked a module. My fault. So don't "bad mouth" a GM HEI Ignition
in my presence. Nothing else even comes close to it. Your opinion WILL vary.
Jim Hupy
Salem, Oregon
On Fri, Jan 31, 2020, 1:23 PM James Hupy wrote:
> Back from my first round of errands. So, as electrical loads increased in
> automobiles, shortcomings in electricity producing devices did not keep
> pace with demand. Permanent magnets were only so strong, so their
> electrical fields were limited. No field strength means no high amperage
> output. Commutators would wear carbon brushes out quickly, and required
> frequent maintenance to remain in top form.
> Soooooo, along came inside out generators, they rotated the magnetic
> fields (called rotors), and took current off a stationary winding called a
> stator. Several incarnations were developed, but a wye (Y) configuration
> pretty much became the standard. 1 end of each winding (there were 3) were
> joined together, and each other ends were attached to a separate diode.
> (Diode trio) 120 ° out of phase with each other. Regulation is a simple
> matter of turning the field off and on, thereby limiting field strength and
> thusly ALTERNATOR OUTPUT. The GM design pretty much rules the roost.
> During this time the solid state devices (transistors, thermistor,
> solid state diodes, etc.) took giant leaps forward. Integrated circuits,
> etc. became commonplace. Uses varied from microwave ovens to spacecraft.
> Cellular telephones, home computers, etc.
> I will follow up more later. File length limits.
> Jim Hupy
> Salem, Oregon
>
> On Fri, Jan 31, 2020, 12:16 PM Johnny Bridges via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> Actually, my fave is the 70s Mpoar setup. The only failures I have seen
>> with them is a) the dual ballast resistor and B) poor grounding of the
>> module. The resistor is an easy fix, Ohmite is Your Friend. The second
>> time rust got under the mounting bolts in my 340 car, I took the Dremel and
>> ground down to bare metal on the module and the inner fender and used my
>> old American Beauty iron to solder a braid between them. Never had a
>> problem
>> with it after that, and while we built it back to go, the C/R wasn't
>> really stupid - 10.5:1 I put copper plug wires which wiped out every AM
>> radio for
>> half a mile. When I was driving it sensibly it used a graphite coil wire
>> which shut the noise up. Playing Stoplight Choose-Off, it got the solid one
>> back, and devil take the radio.
>>
>> --johnny
>> --
>> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
>> Braselton, Ga.
>> I forgive them all, save those who hurt the dogs. They must answer to me
>> in hell
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
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| Re: HEI vs Petronix [message #351828 is a reply to message #351793] |
Sat, 01 February 2020 15:35 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
|
Senior Member |
|
|
Well, the parts house educated me. I looked for Pertronix Ignition. I got seven or eight hits, ALL modules for HEL and its successors. And Furd and Mopar modules as well. Which makes me wonder now. How much HEI OEM stuff was made by Pertronix as a GM vendor? The ones listed go from a stock 4 pin to a seven and a (I assume later) multipin with two plugs.. I sus[pect it works on distributorless engines. Whoulda thunk?
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
|
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