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Full voltage to HEI?

PostPosted: Tue Jun 10, 2008 8:15 am
by TopNX75
Hi everyone,

I use a MSD ignition setup in the vega and it's been years since I fooled around with anything HEI.
I was adjusting the timing in a buddys car the other day and I noticed he had an old chrysler style ceramic resistor in line on the main HEI power lead.?!?
If I remember correctly, didn't we feed the HEI with full voltage?

Thanks in advance for the help!

Sean

Re: Full voltage to HEI?

PostPosted: Tue Jun 10, 2008 10:19 am
by cjbiagi
Yes, the HEI should receive full battery voltage.

Re: Full voltage to HEI?

PostPosted: Tue Jun 10, 2008 2:46 pm
by TopNX75
Thx Clyde,,

u tha man..

Re: Full voltage to HEI?

PostPosted: Thu Jun 12, 2008 2:38 pm
by rickhunter1max
Full voltage straight from the battery I'm having starting problems :?: :shock: maybe because I running a denso start that has 2 wire battery and solenoid and I ran both purple and tan together

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Re: Full voltage to HEI?

PostPosted: Tue Sep 01, 2009 10:34 pm
by sayporsha
I will be installing an HEI distributor in my 73 Vega soon. Can someone tell me where to connect the non-resistance wire to a full 12v for start & run on that car?

Sorry for resurrecting such an old thread, but I'd rather do that than start a new one. Besides, this thread looks relevant and it seems like it died prematurely.

TIA,

Re: Full voltage to HEI?

PostPosted: Tue Sep 01, 2009 10:52 pm
by 72 SS PNL
they way i do it grab the large gauge red wire for the HEI from any 70-80's gm vehicle , pull it out of the harness connector , you have to bend a little tab to be able to pull it out

then pull the harness connector on the vega , pull the resistance wire out and insert the red HEI wire(dont forget to pull the lock tab back out) , reinstall the harness connector

harness connector = the big 1 on the fire wall

GM only runs the resistance wire from that connector to the coil

Re: Full voltage to HEI?

PostPosted: Wed Sep 02, 2009 1:02 am
by chevyart
hey 72 sspnl. you completely lost me on what you are doing here. are you splicing something in. i seek knowledge. can you explain. also what does rick hunter mean when he says he has a 2 wire battery and solenoid. can you help me on that one thanks chevy art

Re: Full voltage to HEI?

PostPosted: Wed Sep 02, 2009 1:22 am
by 72 SS PNL
ill post up a pic of the reverse light wires i grabbed with the t50 i got from the monza , the ends are the same as i did what i was talking about to get the wires out

i also did this in my 68 elco for the MSD i put in it , i searched to find the longest wire possible for it

no cutting is required , all you are doing is replacing the resistance wire with the stock HEI wire

Re: Full voltage to HEI?

PostPosted: Wed Sep 02, 2009 5:46 am
by spencerforhire
A simpler solution- use the pink wire that's found on the oil pressure switch; it provides power for the fuel pump(only when there's oil pressure). It originates inside the car where it's spliced into the same circuit as feeds the resistance wire. If you're still using the OEM fuel pump in the tank, splice into the wire; if you're not, cut it out of the connector as it has the right terminal to plug right into the HEI.
Also, for clarification, the Denso starter has no third terminal to feed full 12volts out to the points while cranking.

Re: Full voltage to HEI?

PostPosted: Wed Sep 02, 2009 11:10 pm
by 72 SS PNL
i had to pick up some parts i won on ebay , and got back to late , ill get pics tomorrow

Re: Full voltage to HEI?

PostPosted: Wed Sep 02, 2009 11:56 pm
by chevyart
hey spence i would like to be your car insurance agent. he probably can afford to buy a new cadilac every year chevy art

Re: Full voltage to HEI?

PostPosted: Thu Sep 03, 2009 12:17 am
by sayporsha
Thanks for the info guys, that's exactly what I needed to know.

Re: Full voltage to HEI?

PostPosted: Thu Sep 03, 2009 6:26 am
by spencerforhire
Chevart- No insurance agent is getting rich off of me; the "fleet' only carries the bare minimum of coverage, and with good driving records (even the teenagers!) we get off cheap. Besides' "technically" only 4 are actually insured at the same time; I used to juggle them monthly until the agent told me "off the record" to just drive whatever ones I want and call in after the fact if there was an incident.

Re: Full voltage to HEI?

PostPosted: Thu Sep 03, 2009 10:15 am
by chevyart
hey spence sound like your agent is a good agent working for your best interests. back in the 60s i lived in Maine and i didnt even need insurance to drive in the state, but only on the Military base. needless to say i parked the car off base. chevy art

Re: Full voltage to HEI?

PostPosted: Fri Sep 04, 2009 1:07 am
by 72 SS PNL
ok art , grab our viewing glasses , pencil and pad of paper , lol

main harness connector at firewall

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bolt that holds the engine harness to the interior harness , you need to undo the bolt and pull the harness from the interior connector

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then you will have this , when you pull and flip the connector , and you can see the male spades

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here is the male spade outside of the connector , you can see the right side(in the pic) is not attached at the base , this is the locking tab that holds the spade in the connector , use a screw driver or something to bend the end towards the center , then pull the wire from the harness side

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in the case to go with this post , the resistance wire has a braided sleeve , where the regular wires use a plastic sleeve , so its easy to spot , now any factory equipped GM vehicle with a HEI from the 70's to mid 80's all use the same spade terminals , so finding 1 at the junk yard shouldnt be to hard

just cut open the stock harness from the donor vehicle , and pull the large red wire for the HEI out of the harness , and in similar fashion to the pics above pull the male spade from the connector

then use a screw driver or similar to pry the lock tab back out some , so that when you insert it into the conector for your car , then run the wire with the factory wires to the dist , and plug in

now this will work for any of the wires , i rebuilt the fire fried harness in my 68 elco , as well as added the large red wire for the HEI to run my MSD box

cutting and using a regular butt connector might be easier , but will cause issues down the road , even GM and chrysler use heat shrink style butt connectors , which will provide a sealed connection as well as making it more vibration resistant

but why cut and splice , and add possible issues down the road when you can add a good solid wire from point A to B

hope this helps alot of you out there