HEI wire question - The 1947 - Present Chevrolet & GMC Truck Message Board Network

sleepertruck72 · 04-30-2009, 06:21 PM

I am wanting to replace my HEI wire that is ugly looking and spliced up. It gets 11.32 volts with the key on. It is spliced with a 700r4 12v, and that gets the same 11.32. My question is on the IGN Unfused part of the fuse box, Do I need to add a fuse of some sort ? I really dont want to clip a connector on the cab side of the fuse box, but the terminal is tied in with another fuse on the back of fuse box.I did check that terminal and it has 12.34 volts going to it. I cant seem to slide out the terminal so I can run the wire from the back of the box so its not noticable. What am I doing wrong ? Thanks in advance

PanelDeland · 04-30-2009, 07:18 PM

If I understand what you're asking.There is a small bolt(5/16ths I think) in the center of the firewall side of the fuse block.Remove it and you can unplug the underhood connectors.I would find a good terminal to hook the 700R4 wire to.Then the wire that originally ran to the ignition can be rerun.There is a connector in the plug that can be taken out and replaced.Connect a new wire to it and run it as you want. then you will have a plug that looks stock and a wire that should have the full 12 volts for ignition.I'm not very familiar with the wiring on a 700 so maybe someone will chime in on that.The best write up I have seen on HEI wiring is by member shifty in the FAQ's section.It will give you the part # for the terminal that goes in the engine side of the firewall plug and also tells which wire it is.It's written for a 6 cyl but is the same.
Hope this helps some.

**VetteVet** · 04-30-2009, 07:26 PM

Here is Shifty's thread.
http://67-72chevytrucks.com/vboard/s...d.php?t=148346

sleepertruck72 · 04-30-2009, 11:53 PM

Thanks PanelDeland, and Vettevet. Thats exactly what I will need for my 6 banger 67. I ended up messing with the fuse box until I got the connector out and was able to finally finish that up with a spare fuse box for connectors. Now my tranny and HEI have the 12volts they should. The way the PO had the wires hacked up was really strange. It worked but I ended up cutting off his puny 14 ga. wires and used 10 ga. The HEI previously had 11 volts as did the tranny. They worked, but now their happy with 12v The funny thing is, all this work was done because I changed my heater core, so I ran my spark plug wires behind the headers, hooked up those new wires for the tranny and HEI and I almost stripped and painted the inner fenders. Good thing I talked myself out of it

**mr48chev** · 05-01-2009, 12:12 AM

I just used a female spade wire end and 10 gage wire hooked to the terminal you described. I run my fuel pump to the other one. You don't need it fused and I don't see any reason to hack into the fuse block.

I folded the original ign wire over and taped it into the harness but that isn't really the best idea and I'll fix that when I do some other wiring work in the engine compartment. I've run the HEI this way for over six months and it is one of the best things I have done on the truck.

04-30-2009, 06:21 PM	#1
sleepertruck72 Registered User Join Date: Nov 2007 Location: Turlock California 95380 Posts: 2,075	HEI wire question I am wanting to replace my HEI wire that is ugly looking and spliced up. It gets 11.32 volts with the key on. It is spliced with a 700r4 12v, and that gets the same 11.32. My question is on the IGN Unfused part of the fuse box, Do I need to add a fuse of some sort ? I really dont want to clip a connector on the cab side of the fuse box, but the terminal is tied in with another fuse on the back of fuse box.I did check that terminal and it has 12.34 volts going to it. I cant seem to slide out the terminal so I can run the wire from the back of the box so its not noticable. What am I doing wrong ? Thanks in advance __________________ 72 C20 Longbed 05 1500 Z71 Last edited by sleepertruck72; 04-30-2009 at 06:23 PM.

04-30-2009, 07:18 PM	#2
PanelDeland I am a Referee of life. Join Date: Jun 2000 Location: Greensboro N.C. Posts: 13,992	Re: HEI wire question If I understand what you're asking.There is a small bolt(5/16ths I think) in the center of the firewall side of the fuse block.Remove it and you can unplug the underhood connectors.I would find a good terminal to hook the 700R4 wire to.Then the wire that originally ran to the ignition can be rerun.There is a connector in the plug that can be taken out and replaced.Connect a new wire to it and run it as you want. then you will have a plug that looks stock and a wire that should have the full 12 volts for ignition.I'm not very familiar with the wiring on a 700 so maybe someone will chime in on that.The best write up I have seen on HEI wiring is by member shifty in the FAQ's section.It will give you the part # for the terminal that goes in the engine side of the firewall plug and also tells which wire it is.It's written for a 6 cyl but is the same. Hope this helps some. __________________ The 47-present Chevrolet and GMC Truck Message Board Network,it's owners,moderators,members,and associates of any type should not be held responsible for my opinion. You can't fix stupid,not even with duct tape. "My appearance is due to the fact that "GOD" does punish you for having too much fun!" Barrett-Jackson has perfected alchemy,they make rust into gold! "You can lead a horse to water but you can't saddle a duck" "Cleverly disguised as a 'Responsible Adult' "Sometimes your Knight in shining armor is just a retard in tinfoil"

04-30-2009, 07:26 PM	#3
VetteVet Msgt USAF Ret Join Date: Jan 2005 Location: Kalamazoo, Michigan Posts: 8,725	Re: HEI wire question Here is Shifty's thread. http://67-72chevytrucks.com/vboard/s...d.php?t=148346 __________________ VetteVet metallic green 67 stepside 74 corvette convertible 1965 Harley sportster 1995 Harley wide glide Growing old is hell, but it beats the alternative.

04-30-2009, 11:53 PM	#4
sleepertruck72 Registered User Join Date: Nov 2007 Location: Turlock California 95380 Posts: 2,075	Re: HEI wire question Thanks PanelDeland, and Vettevet. Thats exactly what I will need for my 6 banger 67. I ended up messing with the fuse box until I got the connector out and was able to finally finish that up with a spare fuse box for connectors. Now my tranny and HEI have the 12volts they should. The way the PO had the wires hacked up was really strange. It worked but I ended up cutting off his puny 14 ga. wires and used 10 ga. The HEI previously had 11 volts as did the tranny. They worked, but now their happy with 12v The funny thing is, all this work was done because I changed my heater core, so I ran my spark plug wires behind the headers, hooked up those new wires for the tranny and HEI and I almost stripped and painted the inner fenders. Good thing I talked myself out of it __________________ 72 C20 Longbed 05 1500 Z71 Last edited by sleepertruck72; 04-30-2009 at 11:53 PM.

05-01-2009, 12:12 AM	#5
mr48chev Registered User Join Date: Jul 2007 Location: Toppenish, WA Posts: 15,838	Re: HEI wire question I just used a female spade wire end and 10 gage wire hooked to the terminal you described. I run my fuel pump to the other one. You don't need it fused and I don't see any reason to hack into the fuse block. I folded the original ign wire over and taped it into the harness but that isn't really the best idea and I'll fix that when I do some other wiring work in the engine compartment. I've run the HEI this way for over six months and it is one of the best things I have done on the truck.



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