upgrading to HEI from Coil
Thread Starter
Instructor
Joined: Jul 2005
Posts: 140
Likes: 0
From: Sunnyvale TX
upgrading to HEI from Coil
HI,
i have a 74 and it has been upgraded to HEI ignition as opposed to the old coil.
now with this upgrade, is there more to it than just putting in an HEI distributor??
the car used to run perfectly when we had first started it now after i replaced all the brake lines (car sat for about a month) it has decided to be hissy when starting.
it wants to just click at us however although the battery was low, it does not seem low enough to cause this. it should at least be turning over instead of that clicking..
also is it possible that somehow the battery could be draining??
THANKS
JIM
i have a 74 and it has been upgraded to HEI ignition as opposed to the old coil.
now with this upgrade, is there more to it than just putting in an HEI distributor??
the car used to run perfectly when we had first started it now after i replaced all the brake lines (car sat for about a month) it has decided to be hissy when starting.
it wants to just click at us however although the battery was low, it does not seem low enough to cause this. it should at least be turning over instead of that clicking..
also is it possible that somehow the battery could be draining??
THANKS
JIM
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
If its just clicking instead of turning over, it can only be a couple things. Battery, Battery connections, ground connections, starter.
I would inspect all the battery connections, charge the battery (with a real battery charger) and see what you have.
Once it does start, verifying battery drain is a good idea, it will require an amp meter which you will place between the Pos terminal on the battery and the Pos battery cable. Yould should measure less than 100 Miliamps. If it is more, someting is wrong.
I would inspect all the battery connections, charge the battery (with a real battery charger) and see what you have.
Once it does start, verifying battery drain is a good idea, it will require an amp meter which you will place between the Pos terminal on the battery and the Pos battery cable. Yould should measure less than 100 Miliamps. If it is more, someting is wrong.
Drifting
Joined: Jan 2006
Posts: 1,944
Likes: 22
From: Yooperville MI
Are you using the old coil wire to power the HEI? If so, it will work for a short time and quit because it is a resistance wire. You'll need to run a 10ga wire from the pink wire at the ignition switch to the + terminal on the distributor. This will provide the correct current to operate the HEI from the same connection point as the factory. Make sure to solder and shrink tube the splice at the pink wire.
You can purchase the distributor connector from Summit or a kit with wire and connectors from....http://www.madelectrical.com/
You can purchase the distributor connector from Summit or a kit with wire and connectors from....http://www.madelectrical.com/
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
On the points system, there are two wires to the coil. One (from the fuse block) is a resistance wire and only gives 9 volts to the coil. The other (from the starter) gives a full 12 volts to the coil but is engaged only during engine start. You want to eliminate the wire from the starter and the wire from the fuse block needs to be changed to a standard wire to give the full 12 volts to power the HEI correctly.
Drifting
Joined: Oct 2003
Posts: 1,352
Likes: 18
From: Dallas Texas
HI
no points! converted to HEI! trying to find out where is the best place to get power to go to the + on the distributor! Willcox suggested the starter...was trying to find out where on the starter!
Thanks
no points! converted to HEI! trying to find out where is the best place to get power to go to the + on the distributor! Willcox suggested the starter...was trying to find out where on the starter!
Thanks
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
I realize that just trying to explain the two wires that were originally used to help you figure it out. Can't use the starter because as soon as you release the key on startup the engine will die. Starter wire only used with points and only helps engine to start. Once the engine is running that line goes dead. Must use the wire coming from the fuse block. This was the original coil wire and should still be there. Measure the voltage on it with the ignition ON and it should be about 9 volts. Replace this resistor wire with a standard wire and you will now have 12 volts available to power the HEI.
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Drifting
Joined: Jan 2006
Posts: 1,944
Likes: 22
From: Yooperville MI
The pink wire is located at the ignition switch at the lower section of the steering column. You want to splice into the pink wire with an additional 10ga wire that will be routed to the + terminal of the distributor. This is typical for any older GM vehicle conversion to HEI.
