GM HEI: Cheap and Extremely Effective Ignition Upgrade

If it's broken or just needs tweaked

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Pinhead
Posts: 611
Joined: Thu Jan 04, 2007 2:26 am

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Pinhead » Thu Feb 23, 2012 1:26 pm

They should work, though may not be optimal; DC resistance isn't the same as AC reactance. In other words, the ohms can be the same but the mh could be different.

I doubt it'd be unusable, though.

klougnot
Posts: 149
Joined: Wed Jun 02, 2010 1:05 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby klougnot » Thu Feb 23, 2012 8:12 pm

Pinhead wrote:They should work, though may not be optimal; DC resistance isn't the same as AC reactance. In other words, the ohms can be the same but the mh could be different.

I doubt it'd be unusable, though.


Hi Pinhead,

Good News! I have after a very long delay figured out how to hook up all the HEI stuff and Well coils so it will fit on my 1976 CB750. The key was to mount the coils to the bottom of the battery box and the HEI modules under the seat. I followed the directions on page and grounded the blue and yellow with the white tube and made the boost circuit as well. The only thing I a missing is plug wires that will connect to the coils. I tried buy plug wires for a Caviler, but they were 16 OHMs and was not sure that would work.

Check out the pics and let me know what you think. If you can help me with the plug wires I can do a quick test and report back.
Attachments
2.JPG
Coils mounter under Cb750 battery box
2.JPG (125.55 KiB) Viewed 7949 times
1.JPG
Hei Modules mounted on top of the battery box.
1.JPG (128.07 KiB) Viewed 7949 times

klougnot
Posts: 149
Joined: Wed Jun 02, 2010 1:05 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby klougnot » Fri Feb 24, 2012 4:55 pm

Pinhead,

I think I am all set on the wires got the Accel Superstock copper core wires. Should be ok.

Pinhead
Posts: 611
Joined: Thu Jan 04, 2007 2:26 am

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Pinhead » Fri Feb 24, 2012 6:07 pm

Did you install some type of electronic pulsing system to replace the points?

For the plug wires, I just bought a set of DIY Accel V8 plug wires and cut them to length, using the Honda factory plug caps.

klougnot
Posts: 149
Joined: Wed Jun 02, 2010 1:05 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby klougnot » Fri Feb 24, 2012 8:59 pm

Pinhead wrote:Did you install some type of electronic pulsing system to replace the points?

No just using the cb650 rectors and the backing plate I had fabed up page 6 of what is becoming a War and Peace of ignition threads viewtopic.php?f=4&t=3142&start=75.


For the plug wires, I just bought a set of DIY Accel V8 plug wires and cut them to length, using the Honda factory plug caps.


I got the super stock 3008 kit with the plug ends pre attached and I need to cut to length and crimp. I will use Iridium plugs. Hopefully everything will go well if not I will probably put the whole mess in a flat rate box and ship it to you to keep me from entering the HEI dark hole that others have fallen into.

klougnot
Posts: 149
Joined: Wed Jun 02, 2010 1:05 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby klougnot » Mon Feb 27, 2012 10:34 pm

Just when you thought it was never going to happen here it is a 1976 CB750 with CB650 reflectors and rotor triggering GM HEI modules and coils.

http://www.youtube.com/watch?v=0ejZMdsg17o&feature=youtu.be
Attachments
cowboy-sunset.jpg
Riding off into the sunset
cowboy-sunset.jpg (55.42 KiB) Viewed 7929 times

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Volker_P
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Location: southern Germany

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Volker_P » Tue Feb 28, 2012 2:03 am

All right, there is a good spark.
But does it start and run? :wink:
Cosky's great (free) online manual: http://cosky0.tripod.com

forum links to common technical issues

klougnot
Posts: 149
Joined: Wed Jun 02, 2010 1:05 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby klougnot » Tue Feb 28, 2012 7:10 am

Still trying to battle my wiring mess, but i am hopeful it will run the way it's supposed to. I'll be working on it over the next couple days and report back. Do you think I can use a timing light when turning over with the starter to check timing?

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Volker_P
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Volker_P » Tue Feb 28, 2012 7:39 am

Sure, you should get the F1.4 and for the other pair the F2.3 marks then.
Cosky's great (free) online manual: http://cosky0.tripod.com

forum links to common technical issues

klougnot
Posts: 149
Joined: Wed Jun 02, 2010 1:05 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby klougnot » Tue Feb 28, 2012 8:32 am

Thanks Volker!

I am so excited to see this thing make spark that I can hardly believe it! I must confess I had my doubts that it would do anything especially after so many attempts by School_Da_Geek. So for it to just make a spark I am thrilled! I will report back with findings. The cowboy in the sunset pic was just for fun. Sorry Geek I just could not help myself.


klougnot
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby klougnot » Sun Mar 04, 2012 5:20 pm

Pinhead wrote:Epic.



Yeah, no kidding and the saga is not over! Looks like I am only getting spark on 2 cylinders. Not sure what I did wrong so I started checking stuff and got no where.

Loudhvx
Posts: 37
Joined: Tue Aug 23, 2011 5:51 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Loudhvx » Mon Mar 05, 2012 2:52 pm

Since you basically have two of everything, you should be able to do some swapping of parts/wires to see if the problem follows a particular part.

Often, during construction, something can get shorted by touching a wire or frame unexpectedly and bam that's it, dead igniter or pickup or diode.

Also, make sure the diode directions are right. That is critical.

I sent you an email reply.

Loudhvx
Posts: 37
Joined: Tue Aug 23, 2011 5:51 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Loudhvx » Mon Mar 05, 2012 8:35 pm

Remember to always leave some sort of path for the coil energy to discharge through, otherwise the coil and/or igniter can die instantly. That means both high tension leads from a coil must have a path to each other somehow. They can just touch each other, or you can have spark plugs in the wires and have the plug bodies touch each other, or you can have both plug bodies touching any piece of metal. But if you leave one or both plug wires open where a path cannot be found for the discharge, the coil will find a path internally (it is then dead, but may not appear dead to an ohm meter test), or the igniter will find a way to discharge the primary side internally (it is then dead, but may not appear dead to an ohm meter test).

To test the igniter and coil, hook everything up except the G terminal. Then just very briefly apply and remove voltage to the G terminal. Removing the voltage will cause the spark. The voltage can be anywhere from 2 volts to 12v. But make sure G is not cnnected to anything else.

klougnot
Posts: 149
Joined: Wed Jun 02, 2010 1:05 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby klougnot » Mon Mar 05, 2012 9:03 pm

Thanks Lou,

This little test seems to work ok. I am not sure if earlier testing where the spark plugs may have slide off the top of the engine damaged my coils or not. My primary side of both coils is measuring near zero.


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