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Discussion Starter #1
Hi everyone,

So I recently rebuilt my engine and in the process upgraded my points distributor to an HEI, and my factory starter to a mini starter. The factory starter had 3 terminals (Battery+, S, R), and the new starter has 2 terminals (Battery+, S). Based on the instructions and what I read online, the R terminal was the resistor wire bypass for the coil (so that the coil would have 12v on startup) and that for HEI distributors it could be removed (So I did just that). I also removed the resistor wire that was connected to the coil from the bulkhead connector, and replaced it with a 12-gauge wire (This will be the power for my HEI).

Note: I checked the wiring diagram and determined that this pin on the bulkhead connector ties into the ignition switch (12-P wire from the bulkhead on the factory wiring diagram)

So with the wiring set up as it is (to my understanding), when the key is in the RUN position the wire to the starter S terminal should read 0V and the 12-gauge wire to the coil should read 12V. Then when the key is switched to the START position, the wires to both the starter S terminal and coil should read 12V.

Upon testing, when the key is in the RUN position I am reading 0V to the starter S terminal and 12V to the coil (which makes sense). However, when testing with the key in the START position, I am reading 12V to the starter S terminal and 0V to the coil (which does not makes sense?). I also tested the IGN terminal on the fuse box and got the same results.

Unless I am mistaken, the HEI requires 12V in RUN and START. So is there a different terminal that I should be using instead of the IGN?

Thanks for the help!

PS: Sorry if this ends up being a double posting. My page crashed when trying to post the first time and I couldn’t find anything to suggest that the tread had actually been posted.
 

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An ignition switch from a 75 or later vehicle might be the solution if you have a 69 vehicle or later with the same type of switch. If not, some sort of relay system may be required.
 

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Discussion Starter #3
If I were to replace the ignition switch, is there any way to know before buying it if it would pass 12V in RUN and START?
 

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No way I know to be sure. If you can find an electrical whiz, maybe comparing wiring schematics would be helpful.
 

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If you have an IGN or IGNITION terminal on the fuse box, check it for having battery voltage at both run and start key positions to ground, cold everywhere else. If hot in those two positions, use that to power up the HEI, IGN to BATT on the HEI cap, done. 12 or 10 gauge wire will work just fine.
 

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Discussion Starter #6
I checked each of the terminals on the fuse box and unfortunately none of them are hot in RUN and START (Except for the battery which is always hot). What I am currently trying is one of the diode wires from the starter. They are supposed to be a single direction flowing wire that will supply the 12V during cranking from the starter (essentially a replacement for the R terminal on the starter). If anyone has tried one of these before I'd love to hear your thoughts. Ill post an update with my results.

Here is a link to the diode wire I'm talking about if anyone is interested: Summit P/N - SUM-890175
 

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What you're describing sounds like you have a '67 in which the ign wire is cold while cranking. I "believe" the solution is to install a '68 ign switch, which has both the run and start wires hot while cranking. I do not know if it is a plug and play swap, you'll have to do a little digging around. It has been posted here before. Ign switch from 69 and later is a totally different deal
 

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James garage picture shows a 69, fwiw.
 

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See attached diagram for the 69 Camaro Ignition switch.

The Pink Wire is HOT in the RUN and START Position. At the bulkhead connector it is a resistance wire to the coil. When HEI it would go to the BAT side.

If the resistance wire was changed at the bulkhead to to the BAT side of the HEI it would still be HOT in both the RUN and START position.

The YELLOW wire from the starter also goes to the BAT side and is only HOT in the START position to give full BAT power to the coil when starting. Eliminate the YELLOW wire when using HEI as you already have full BAT power to the coil if the resistance wire was changed at the bulkhead connector.

So either your switch is bad (or wired wrong) or the wire from the bulkhead connector is the problem.

69 Ignition Diagram.JPG
 

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I'm having the same problem with my 67. Have a mini starter with a HEI dissy and not sure how to wire it up. A previous owner had hacked up the wiring so I'm in the process of working out where the wires go and replacing them with the correct coloured wires. Trying to work out how to get power to the HEI when the key is in the start position. Buying a new wiring loom is out of the question as my car has been converted to right hand drive, (I'm from Australia), so the wiring would have to be modified to fit. Thinking of using a relay switch to run a wire from the battery to the HEI and run a wire from the start terminal to activate the relay when the key is turned to Start and deactivates when the key is at Run/Ign. This way I can still use the stock purple wire as normal to power the HEI when running and not have to worry about power going back to the starter from the second wire.
 

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Graeme, you may be able to feed your coil from the purple wire, as long as you put a diode in the feed wire to keep from back feeding the starter solenoid. That should do away with needing a relay.

Anyone have any thoughts on doing it that way?
 
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Discussion Starter #12
I used a diode and its been working great. When I was dealing with this problem I didn't want to mess around with installing a relay, which is why I went with the diode. What I ended up doing was removing the old resistor wire leading from the bulkhead connector to the distributor and replacing it with a regular 12ga line. Then hooked up the diode wire to the starter. After the diode is hooked up you just have to run that wire back up to the HEI and connect both the diode wire and the new bulkhead wire into the HEI BAT terminal.
 

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A diode is workable. Please be aware, they can fail, both ways, no continuity, continuity both directions.

Please be aware, most of the mini-starter manufacturers offer a solenoid for their units that has the R terminal, simple swap solenoids. Contact them directly.

If no workable IGN terminal, remove bulkhead connector on firewall side, new terminal from GM, swap resistor wire terminal to full voltage wire, tape off resistor wire connector. This will give you full battery voltage power to the HEI on run.

Diode off the S solenoid terminal, or, alternate solenoid.

The resistor wire in our cars is silver stranded for the resistance, and about 7 feet long, I do not recommend removing it from its loom, but simply taping both ends off and then, to the loom, so it remains in the loom/car.
 

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greame.

your RH drive will not affect how the HEI gets its +12v unless the ignition switch has been rewired for some reason. If the fuse block is still next to the DS kick panel just run a 12 gauge wire (it can be any color but white is stock) from IGN terminal to the + terminal of coil. The stock white resistance wire that did go to the coil you can just tape back in the loom
 

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Unfortunately a lot of the wiring under the dash has been butchered, wires have been cut and other wires joined up using different colours and the ignition switch as been rewired with different coloured and extra wires. I have a wiring diagram and am slowly sorting it all out, replacing the wires with the correct coloured wire.
 
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