Throwing my hands up on this ignition!

[Bewy]

The only way to know for sure that your ign box is 'fine' is to.....substitute it with another one that you know works.
An MSD coil I bought a couple of months back is made in China. Well that is what the sticker says!!!
Very good advice above to use your dist to trigger a GM HEI module. Dead simple to hook up, cheap, big high energy spark. Get an E core coil to use with it to get the most out of the system.

 

[famous bob]

Isn't there some other brand of multispark ignition without all the MSD issues?

it has been said , and advertised that the newest ''petronics'' set up fires multiple sparks all the way thru the rpm range .--------??

 

[Mattax]

Actually, you may be able to test the MSD unit.
The instructions from Autotronics that came with the 6A, 6, etc explain how to check the box.
Holley has changed the instructions sot I dont know whats in them now, but the units are essentially the same.

 

[Valkman]

The only way to know for sure that your ign box is 'fine' is to.....substitute it with another one that you know works.
An MSD coil I bought a couple of months back is made in China. Well that is what the sticker says!!!
Very good advice above to use your dist to trigger a GM HEI module. Dead simple to hook up, cheap, big high energy spark. Get an E core coil to use with it to get the most out of the system.

When everything running the spark is fine, the car runs like freight train. Which makes me think it's something else. It is possible the box is the problem, but with all of the other variables I'd like to see if there's something else first.

 

[pishta]

it has been said , and advertised that the newest ''petronics'' set up fires multiple sparks all the way thru the rpm range .--------??

Id like to see that. 6000 rpm is 400 sparks per second..Most multi strike boxes are CD as well and it just cant define a multi strike after about 3500 RPM so its advertised as a long spark, 20 degrees crank. Hard to beat an old Mallory made Hyfire series.

 

[Professor Fate]

Okay, I'll bite, but for the last time... I'm a glutton for punishment.

I have an MSD a high voltage coil and a stock electronic distributor.

It ran great with MSD that is when it ran.

The box I'm using isn't an actual MSD it's Summits version and I think it's working fine.

People have been using MSDs for ever, and yes maybe there not as reliable as they once were but for most part they still work.

My friend had a Mallory High Fire so I tried it and "like that" it ran great! I set out to find one these High Fires and they were not available, so I did a little research and come find out that it appears the Summit unit is made by the same people.

it ran great till it didn't.

ran great again till it didn't.

It's an MSD... It's not an MSD... It's a Summit MSD knockoff... It's an MSD again... It's a Summit Mallory knockoff...
PLEASE PLEASE PLEASE figure out what you have, and post accurate information. Model numbers, part numbers. Ignition box, coil, distributor. MSD, Summit, Pertronix make many different styles and models of ignitions and coils and they're NOT ALL THE SAME. "Wired according to MSD's instructions" is meaningless if it's not an MSD... And saying "it ran great until it didn't" is no help at all- is there spark, did you actually test for spark? What type coil are you attempting to use? They aren't all interchangeable.
And please quit saying "it's working fine". It isn't. That's why you're here. And saying "they must be good otherwise they wouldn't keep selling them" is a cop out. The market is full of garbage that people keep buying. Not saying your system is, but I don't know what system you have.
So, if you want "a little less option (sic) and maybe some constructive help", start by giving us actual information, and stop assuming it can't be this or that without actually testing the component- it is, after all, not working.

 

[Valkman]

Okay, I'll bite, but for the last time... I'm a glutton for punishment.

It's an MSD... It's not an MSD... It's a Summit MSD knockoff... It's an MSD again... It's a Summit Mallory knockoff...
PLEASE PLEASE PLEASE figure out what you have, and post accurate information. Model numbers, part numbers. Ignition box, coil, distributor. MSD, Summit, Pertronix make many different styles and models of ignitions and coils and they're NOT ALL THE SAME. "Wired according to MSD's instructions" is meaningless if it's not an MSD... And saying "it ran great until it didn't" is no help at all- is there spark, did you actually test for spark? What type coil are you attempting to use? They aren't all interchangeable.
And please quit saying "it's working fine". It isn't. That's why you're here. And saying "they must be good otherwise they wouldn't keep selling them" is a cop out. The market is full of garbage that people keep buying. Not saying your system is, but I don't know what system you have.
So, if you want "a little less option (sic) and maybe some constructive help", start by giving us actual information, and stop assuming it can't be this or that without actually testing the component- it is, after all, not working.

What does it matter what brand CDI box it is they work the same way, and they are even wired the same, so the diagnostic should be very similar.

 

[Professor Fate]

"What does it matter what brand CDI box it is they work the same way, and they are even wired the same, so the diagnostic should be very similar."

And here we go again... now is it CDI or multi-spark? Two completely different animals.
Enjoy. Thread unwatched.

 

[RedFish]

If you have poor come and go connections in the cars wiring, none of the ignition systems will work right. I had the same conditions in a bone stock 73 valiant 318 2brl many years ago. Sometimes it would fire right up and run great. Other times no start or slow to start and ran like crap. I changed the coil and coil wire. I bought chrome box ECU. Almost every time I fecked with it, it would fool me into believing I had fixed it, until it went to chit again. I threw my hands up too. Parked that car and drove a Geo for about 2 years. When I had to put it back in the street, It fired right up and ran fine for nearly a month. Then same issues resurfaced.
First poor connection found in the blue wire was at ignition switch connector under dash. Next was same blue wire at bulkhead connector. That electronic ignition and 2brl carb are on my 67 273 today. Never was anything wrong with them.

 

[skykeith]

Unfortunately ignition testing requires test equipment the average person can’t afford to buy just to locate a problem. I used to do ignition work for money and have a Mac ET975 diagnostic oscilloscope, a Uscope, and a thermal camera. That’s over $2000 dollars worth of equipment, but with it you can “see” the reluctor output, the primary and secondary voltage patterns, terminals, coils, and boxes overheating and find out exactly what’s happening. I hate to say it, but there’s no other way to do it other than throwing money and parts at it.

 

[RedFish]

Unfortunately ignition testing requires test equipment the average person can’t afford. I hate to say it, but there’s no other way to do it other than throwing money and parts at it.

That is what I tried to say above. I threw gambles and guesses and dollars at that Valiant for a long time before i finally found the root problem. A good volt meter showed me what a basic test amp could not.

 

[toolmanmike]

Unfortunately ignition testing requires test equipment the average person can’t afford to buy just to locate a problem. I used to do ignition work for money and have a Mac ET975 diagnostic oscilloscope, a Uscope, and a thermal camera. That’s over $2000 dollars worth of equipment, but with it you can “see” the reluctor output, the primary and secondary voltage patterns, terminals, coils, and boxes overheating and find out exactly what’s happening. I hate to say it, but there’s no other way to do it other than throwing money and parts at it.

I sold a few of those ET975's when I was on the truck. The fellows that used them could make them do some impressive things.

 

[Valkman]

Ok taking pishta's suggestions I did bit of checking. The coil read 1.4 ohms across the post and 9.8k ohms internally. Interesting the coil I changed out (an Accel) had the same readings. With the ignition on I read 12v across the coil and as 12v to the source to the Summit box. This tell anyone anything?

 

[RustyRatRod]

"What does it matter what brand CDI box it is they work the same way, and they are even wired the same, so the diagnostic should be very similar."

And here we go again... now is it CDI or multi-spark? Two completely different animals.
Enjoy. Thread unwatched.

You're finally learning.

 

[AJ/FormS]

Make sure your ignition switch will switch reliably and repeatably between crank and run.
Then run the ignition box off relays triggered by those two circuits, and supplied by the same independent battery power source as the box..
Your ignition problems will be over.
-----------------------
FYI
I have powered my 367 with a Jacobs Amp, a modded factory magnetic pick-up distributor, and an ancient apron-mounted sq-top Accell Super-coil (with it's own ballast), as above, since the early 2000s.
The engine is on it's third cam since then, having begun with a 292/292/108 Mopar grind. This system works from 500rpm to 7200 and beyond. Why anyone running with this or less cam, on the street, would need the possible/probable headaches of a CDI, or a Multi-strike, is beyond me.
I love the idea of a CDI, but not interested in walking.
The only part of this system that has ever failed, is the pick-up, which I swapped out on the side of the hiway.
Best of luck to you.

 

[Bewy]

Should not be getting 12v to the coil [+] terminal on a CD type ign system.

 

[famous bob]

Id like to see that. 6000 rpm is 400 sparks per second..Most multi strike boxes are CD as well and it just cant define a multi strike after about 3500 RPM so its advertised as a long spark, 20 degrees crank. Hard to beat an old Mallory made Hyfire series.

dont take my word for it , go read a summit catalog----------

 

[pishta]

I did.....how they do it? CDI supposed to send ~450V to the coil when running. When its ON but not running, there is no switching (dumping of 450V capacitor voltage) so IIRC you may have little to no voltage to the coil. Use an alligator clip on the switched power line to battery + to ensure your start/run voltage is stable and not loose as AJ stated.

 

[448Scamp]

I did.....how they do it? CDI supposed to send ~450V to the coil when running. When its ON but not running, there is no switching (dumping of 450V capacitor voltage) so IIRC you may have little to no voltage to the coil. Use an alligator clip on the switched power line to battery + to ensure your start/run voltage is stable and not loose as AJ stated.

Also noteworthy is the fact that to see an ignition spark 400 times per second would take some seriously sophisticated equipment and cameras. The human eye could never see that. It would look like one continuous spark. And for all intents and purposes it is. It would be nice if Pertronix had some video of that and made it public. If they could do that and prove their claims, they’d sell a kajillion of those boxes overnight.

 

[pishta]

you could see it on an O-scope pretty easily with the right KV probes @ 400hz. I know I could see the individual pulses on an MSD off the timing gun...6 little damper lines at idle!

 

[famous bob]

Also noteworthy is the fact that to see an ignition spark 400 times per second would take some seriously sophisticated equipment and cameras. The human eye could never see that. It would look like one continuous spark. And for all intents and purposes it is. It would be nice if Pertronix had some video of that and made it public. If they could do that and prove their claims, they’d sell a kajillion of those boxes overnight.

Agree, would about have to be continuous , or would look that way ----If I were in the market for an ignition , I`d try it > !

 

[NCmtnDWELLER]

People will hate me for this, but...
Ditch the MSD. Get a nice older chrome box, and new coil. And throw a spare ballast in your glove box.

That ugly *** red cap draws many folks in !!!

 

[RustyRatRod]

That ugly *** red cap draws many folks in !!!

I've never liked anything MSD. Well....I have used a coil or two. But their ignition systems, no thanks.

 

[famous bob]

I've never liked anything MSD. Well....I have used a coil or two. But their ignition systems, no thanks.

disagree with the last two posts, back when we went with higher comp. on the hemi, the orange and chrome boxes wouldn`t fire hot enough , popping all the way thru. The comp. is the only thing we changed , beside intake and head gaskets , an msd 6 stopped the popping and banging , it was the only thing changed that time too .

 

[Bret Tschacher]

I can see the benefit of CDI especialy with high compression. The multispark seems to work at lower rpm and a street application could benefit. I see Summit has a multispark set up. Who knows who makes it for them though.

Biggest benefit of MSD type Ign, is cars with manuals are much harder to stall at low throttle. Also systems that run leaner A/F ratios can see improved performance sort of. An old friend of mine had a 340 4speed in an E body with an MSD that was dam near impossible to stall out. He could side step the clutch from an idle and it wouldn't die, it would just lurch with a chirp of the tires and go.