GM HEI: Cheap and Extremely Effective Ignition Upgrade

If it's broken or just needs tweaked

Moderators: Volker_P, tidd650

SchoolDaGeek
Posts: 147
Joined: Fri Aug 26, 2011 8:36 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Wed Oct 05, 2011 12:44 am

And to Volker, Lou and possibly Pinhead...

Absolutely, when you have spare parts, change them out. Most of this stuff is definitely below the $16 range to hunt and peck, do almost no work.

All I was saying is that this bike could benefit from a later year module in cars for its ignition. The creepy cold hard starts plus starving for air after approx 5000 rpm are the only two reasons I took on this project.
Buy New, Wire Right. BNWR. LOL


SchoolDaGeek
Posts: 147
Joined: Fri Aug 26, 2011 8:36 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Tue Oct 11, 2011 10:43 pm

I have too many irons in the fire, couldn't even get back to the forum Sat. night.

What I found out is that my length measurements were correct but to be able to mount this new thing where the old thing resided threw me for two turns.

I am going to have to reverse the modules and cross the harnesses. Instead of the harnesses being taped correctly on the original diagram, I am going to have to reverse the modules and the bolts to make it fit. The Relay is coming off, I've turned it over, set it straight on the battery and chewed through the metal hole to tie in with the battery box screw. The whole relay is plastic so there is no ground, just support.

I am happy that without access to the bike I can make a new diagram that would be failsafe if used with an 8" piece of aluminum, I am only reducing Lou's recommendations with 80cm2 instead of 100cm2.
Buy New, Wire Right. BNWR. LOL

SchoolDaGeek
Posts: 147
Joined: Fri Aug 26, 2011 8:36 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Tue Oct 11, 2011 10:58 pm

Actually closer to 74.8cm2
Buy New, Wire Right. BNWR. LOL

SchoolDaGeek
Posts: 147
Joined: Fri Aug 26, 2011 8:36 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Tue Oct 11, 2011 11:16 pm

New people can just measure their wires correctly. I have to flip to cross.
Buy New, Wire Right. BNWR. LOL

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

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Loudhvx » Thu Oct 13, 2011 8:42 am

The surface area measurement includes both sides of the plate. A 10cm by 10 cm piece would do the job for two modules (that's 200 square cm surface area for two modules). But it needs to be able to sit flat against the module to ensure proper heat transfer.

The aluminum piece you have looks much bigger than it has to be, (judging by the photo, it's somewhere between 300 and 400 cm square for two modules), so if you need to go smaller, you can.

SchoolDaGeek
Posts: 147
Joined: Fri Aug 26, 2011 8:36 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Thu Oct 13, 2011 10:05 pm

Hi Lou,

I am sorry to be confused again...but I failed calculus twice in college before I changed classes and passed "Biometric Calculus" as my requirement.

I only understand "2pi * radius * height" where just because I have two surface areas I can cut it in half. One soup can cut to 10cm wide, maybe in two pieces...

It fits. I only had to change the modules orientations, pull the "booster" circuit out of the channel and crimp it in the side of my patio door stock.

I like the length because it is jammed up under the tank and gives the whole unit more solidity than a heatsink half it's size but if math wins, then yes, you can measure directly to the edge of the battery box frame and using the OEM harness your modules will reach with your wiring.
Buy New, Wire Right. BNWR. LOL

SchoolDaGeek
Posts: 147
Joined: Fri Aug 26, 2011 8:36 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Thu Oct 13, 2011 10:14 pm

Maybe you mean 100mm2 which would be 10cm2 which would be 5cm x 2cm...per face with the internal channel and another face to each, I could double it. to around a can 'o soup in length.
Buy New, Wire Right. BNWR. LOL

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

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Loudhvx » Sun Oct 16, 2011 8:11 am

A square plate of aluminum, 10cm by 10cm, has 100 square cm of surface area per side, giving 200 square cm of surface area total.

Yes, it could also be notated as 100 cm^2 per side, giving 200 cm^2 total.

The only issue is it should be rather ridgid in order to make sure the module will get full contact with the plate. If the plate can bend, the module won't make full contact. But even then, it'll probably still work fine.

SchoolDaGeek
Posts: 147
Joined: Fri Aug 26, 2011 8:36 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Sun Oct 16, 2011 11:21 am

LOL well I should be good then. My piece of sliding screen door stock is 42mmx200mm which would give me a surface area of 168cm2, about 70% more than I need.
Buy New, Wire Right. BNWR. LOL

SchoolDaGeek
Posts: 147
Joined: Fri Aug 26, 2011 8:36 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Sat Oct 29, 2011 4:01 pm

Well NE Ohio weather sucks this year. N'eer a day to work outside. No garage. So far the module has been reversed and installed but now the seat latch hooks up on the end of the module and it got dark, so I have to hopefully go tomorrow when it is is supposed to be sunny and 49, and saw the module off to a more lower estimate, and round the corner with a file. If the afternoon is warm enough with the sun I may wire the coils, headlight, and bleed the front brakes, but after the coils are wired I will try for a start.
Buy New, Wire Right. BNWR. LOL

SchoolDaGeek
Posts: 147
Joined: Fri Aug 26, 2011 8:36 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Sun Nov 13, 2011 12:26 am

Hello everyone again,

Well the weather has not been great, but I managed to get about 6 hours over three days getting all the details fitted in.

I ran into a bunch of hang ups, namely having to cut down the heatsink because the seat 'tongue' hung up on it, and getting two wires wrong, mistaking the small red/yellow wire for the big red/white wire on the ignition start button (oops) and also realizing that the silkscreen on my relay is incorrect or I don't understand the universal 86/86a diagram, so I had to switch them, and will be adjusting my diagram to reflect that.

In the end, it was getting dark at 4:30 already today and the battery was well run-down from all the attempts, (or me creating a short somehow) but I did hear combustion on the last near-successful attempt without the booster/bias circuit hooked up at that point.

So I am charging the battery overnight and will try again tomorrow. The voltage drops though on my multimeter did indicate I have some corrosion to clean in the fusebox/fuseholders, ignition switch, and run/stop/start switch and button. I will try one more time tomorrow with all the proper connections and then will have to start hunting down the corroded contacts if I have them. I did hear the relay activate and all that, but my voltage was dropping all the way down to around 4.5volts when the starter was engaged. So if the renewed charge doesn't fix that I will have to open things up.
Last edited by SchoolDaGeek on Sun Nov 13, 2011 11:22 pm, edited 1 time in total.
Buy New, Wire Right. BNWR. LOL

SchoolDaGeek
Posts: 147
Joined: Fri Aug 26, 2011 8:36 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Sun Nov 13, 2011 9:42 pm

Ok time to post again...

I am very frustrated at this project. There is too much information for too many configurations. I think that was my earlier reaction in comic strip style.

The most informative article on the whole subject is Lou's: HEREhttp://home.comcast.net/~loudgpz/GPZweb/Ignition/Hei4pinGmIgnitionNotes.txt

The next most informative piece of information is Pinhead's suggestion to isolate the circuits in problem solving, and in order.

But I am seeing many authors here, yet none show their face recently.

I am reduced to having a bias/boost circuit against Lou's original.
Someone tricked me into using the GM coils instead of stock.

So now I have a system that only has been seen once.

And it doesn't work. No spark, checked the forum and there are two others who had to connect the white wires together but NOT to a ground.

And a question was left, and no real response to that question has been answered.

Lou, the original author is a brilliant genious scatterbrain that has all of our minds wondering but would need a team of secretaries to answer everything with Law library skills.

Pinhead picked the right screenname and I joined this forum because of him and only discovered Lou later...

But I think sicj was onto something and no one paid him any notice, or he left regardless.

On the most righthanded side you have the argument for an effective ground. On the lefthanded side you have the argument for an effective voltage "boost/bias" at either start or continuously.

What sicj discovered is that you can also create a "remote ground". Pinhead's proposition was that we cannot lower "ground" but that is an ineffective way to anaylze a circuit.

By sanding shaving and spraying contact cleaner what are we doing then? Do we not do this on our ground contacts too?

Wire harnesses take a volt or so away. Crusty white corroded ground contacts do the same thing.

Metal conducts with resistance...that is why we are building superconductors that use no energy in translation.

Lou has the stock coils and no start button booster circuit on a 4 prong.
Pinhead has the 7 prong, with double diodes and constant bias...
In order to fire the modules you need to introduce bias.

Pinhead suggested reversing the reluctor/pickup leads anywhere on the harness to the lasting impression of sicj. Two others besides myself have used that configuration and no one can answer the question.

Sicj suggested (in theory) that grounding the two negative leads together at least somewhere outside the whizzing and buzzing of the the generator/flywheel could in fact lower the bias needed in Lou's paper in order to stay either generally in an "off state" which is no spark at all (my problem tonight)...

...or making the ground contacts all of one nature allows you to use your original coils with no bias circuit.

Either way, I picked SchoolDaGeek because I am really trying to find out what I am learning here! I've never worked with an ignition that uses voltage drops to either leave the coils in an "off" state permanently, or can be remedied with a loaf of bread stuffed into your headlight.
Buy New, Wire Right. BNWR. LOL

SchoolDaGeek
Posts: 147
Joined: Fri Aug 26, 2011 8:36 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Sun Nov 13, 2011 10:05 pm

So sicj connected the white wires on a four prong.

Will there be damage beyond say 7000rpm or so?
Buy New, Wire Right. BNWR. LOL

SchoolDaGeek
Posts: 147
Joined: Fri Aug 26, 2011 8:36 pm

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Sun Nov 13, 2011 11:26 pm

sicj wrote:So I upgraded my 81 cb650 to this mod. I wired it as shown for the 4 pin module and got no spark. then I tried another version of wiring the system...

I still had no spark. Then all I did was disconnect the ground wires of the ign pickups and the bike received huge spark from the GM coils.

I don't know why either version wired as shown did not produce spark but the moment I took the ground away from the yellow/blue wires (with white sleeves) of the pickups, I then had spark.
Buy New, Wire Right. BNWR. LOL


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