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Old 07-11-2007, 01:27 PM   #1
Luvlegs
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HEI FAQ Questions/Clarifications... wordy too!

I never seem to have much luck getting responses to my threads - I don't ask what back space is that or what drop do you have or what wheels are those... usually just odd issues I run into but they often drop off the current pages quickly with little to no response... ANYWHOOOO, I read an FAQ on HEI's and I am looking for some clarifications that I am sure WILL HELP OTHERS besides myslef. I originally pm'd the author but realized he's been away since 2003 so I'll just paste in what I sent..... (keep in mind I cut up the FAQ for the sections I had questions on so if you see parts missing, that's why).... WARNING - this is WORDY! Any direction or ideas are appreciated - Thanks all!

I have a couple questions when you have a chance - they are related to your FAQ posted about HEI installs.
I put one from a mid 70s I6 nova into my 72 I6 - Starts immediately, runs good. As I turned the dizzy to tune by ear, I ran out of turning room as the vacuum module hit the block. I pulled it, got to TDC, restabbed it - runs fine at idle but on the highway, I cannot get it over 50mph, there is a shudder/shake at speed - (possihly related to this.......At idle, it's hard to describe but the exhaust sounds like "piff piff PUTT piff PUTT piff") - all the wire are correctly landed, connected and good. I added some comments in bold, red, to parts of your write up - its below. Any information you might be able to provide is greatly appreciated! There are ONLY two other thing I am questioning:
1)the effect if my vacuum module is bad.... I
don't belive it is but will be checking it...
2)if the external coil ground wire is not grounded
(would it still run?) - pretty sure it is hooked up but will also double
check that....

anywhoo, here's what I have:

Step 1

To upgrade from points to an HEI, begin by obtaining a known HEI, or freshen one up that is in good shape (i.e. no cracks, gear not worn out, no slop from shaft) from the salvage yard; replacing the pickup coil, cap, and rotor as a minimum. [B]THE EXTERNAL COIL?[/B]

Now, determine which type of wiring harness is in your car. A car that has the ignition switch in the steering wheel column and/or no inline ballast resistor (usually '69 and later), take note of the bypass wire that goes from the (+) post on the coil to the "R" post on the starter solenoid, this wire will be discarded. I AM UNCLEAR ON THIS - I HAD A YELLOW WIRE TO MY COIL - just upline from it, there was another splice off to ???? I DID NOT remove anything else but the wire to the coil after the splice - taped it up


Now that the 'hot' wire(s) have been located, (which is the hard part, by the way, and the #1 reason why this swap goes sour for some) SOUR BECAUSE WE DIDNT REMOVE THE OTHER END OF WHERE EVER THAT ORIGINAL YELLOW WIRE WAS HOOKED? (and still is)disconnect the battery, unhook the wires and tape them off. I did tape off the one that went to the original coil for the points system.

Set the engine at #1 top dead center, (verified by finger-blown-off-the-sparkplug-hole method or both valves closed at #1 while balancer mark is at zero degrees). Remove the cap from the distributor being replaced, and note location the rotor is pointing. Remove the old distributor. DID THIS ALL)After lubricating the HEI distributor gear and installing a new gasket Mine didn't have one but I can always go put one on it, install it so the rotor is pointing in the same position as the old one.

Install the cap, making sure all three leads (black ground wire is easy to forget) I SWEAR THERE IS NO Third wire on mine - just two from the new(used) external coilare in the cap receptacle.

Now, the HEI needs a connection for 12 volts. Install new 12g wire from the (bat) terminal in the cap through the firewall; and splice into the ignition switch's main feed wire, usually pink in color. If this presents a hassle, any ignition-switched source under the dash will do, just don’t use a fuse box accessory connection. I used a terminal in the fuse box labeled "unfused ignition" - works but are you saying I need to move it somewhere else?
If the you have no inline ballast resistor and/or the ignition switch is in the steering column (1 'hot' wire, as verified earlier), this will complete the hook-up, and the bypass wire between the old coil (+) and the starter solenoid (R) can be deleted. NOT SURE AGAIN WHAT THIS IS - If it's the other end of the original yellow wire, will this be detrimental to it running if it's still in place?

Install new HEI wires, gap the plugs around .040"-.045", hook up the vacuum advance to a ported (no vacuum at idle) Can this still be the vacuum line that ran to the original points distributor? source of vacuum on the carburetor. Connect the battery, ensure the engine starts and shuts off, and go for a point-less ride!
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Old 07-11-2007, 03:01 PM   #2
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Re: HEI FAQ Questions/Clarifications... wordy too!

You don't need to move your hot wire. The pink wire is what some guys use for a cleaner looking install, but you don't have to do it that way. I am also running my HEI from the unfused ignition location, but I spliced an inline fuse for safety's sake. As for the vacuum, you can run the HEI from the same vacuum source the old dizzy was using. I'm not 100% certain on the other stuff; maybe someone else will chime in.
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Old 07-11-2007, 03:12 PM   #3
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Re: HEI FAQ Questions/Clarifications... wordy too!

No external coil for HEI, the in cap coil is the only one you need. Here's what I did, easier than trying to figure out what anyone else did. I pulled the old dizzy and chunked it. Stabbed the new one, with #1 cyl TDC, wired the plug wires, vacuum hose was never moved from carb, just unplugged old, plug in new, then I ran a 12 ga wire thru the firewall to an IGN UNFUSED connection in the fuse box and connected it to the dizzy. Cut the old wires off at the junction box and called it a day.
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Old 07-11-2007, 03:49 PM   #4
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Re: HEI FAQ Questions/Clarifications... wordy too!

Krue has it exactly right, biggest issue is to make sure you get a full 12v to the HEI, and not the 7-8 volts coming from the ballast resistor. You may also want to look at the centrifugal weights in your HEI to make sure they are moving freely and advancing the timing at higher speed.
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Old 07-11-2007, 03:54 PM   #5
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Re: HEI FAQ Questions/Clarifications... wordy too!

I didn't cut the wire that I THINK goes to the starter solenoid AND the old coil, I just cut off the part to the old coil. Do I need to remove it from the starter solenoid also?

Ran the power off the fuse panel (Krue - what size inline fuse are you running?) - Then TDC, stabbed it and timing by ear, runs smooth but can't go over 50 mph... I'm thinking vacuum module may be in question....

Will it run if there is no ground? Can't see how but.....

I tried awhile ago here to get a straight answer on what is and isn't HEI - I have a mid 70's dizzy with the external mounted coil (on the block not the dizzy cap) - some said yes, some said no, so I started calling it "electronic distributor".... noone said anything else.
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Old 07-11-2007, 05:22 PM   #6
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Re: HEI FAQ Questions/Clarifications... wordy too!

Call me dumb, but I currently don't have an inline fuse on mine. Thinking about getting an inline blade style fuse from wally world, I'd use a 30 amp or so when I do.
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Old 07-11-2007, 05:27 PM   #7
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Re: HEI FAQ Questions/Clarifications... wordy too!

Ooops, that was Dave that has the fuse... my mistake...(I don't have one either.... yet!)
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Old 07-11-2007, 06:31 PM   #8
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Re: HEI FAQ Questions/Clarifications... wordy too!

I think the post about the coil being in the cap, he may not have noticed that it is an inline 6, since V-8's all have the coil in the cap for HEI. Inline 6's were made both ways. If you aren't sure what you have, the external HEI coil is square, and the Points coil looks like a round tube. The other way is to pull the dist cap and you will see points on a non-HEI.

To check the vacuum on the distributor, take a vacuum hose and put one end on the dizzy vaccum port and suck on the other end to be sure the vacuum module is working it should have some resistance, if you can easily blow in and out, you should replace that part (you can get just that part at an auto parts store). It should still run just fine without the vacuum module working, (not perfectly but it wouldn't prevent you from going over 50mph).

The points wire going the the distributor has a special wire that limits the voltage, (ballast resistor). Mine was originally spliced into a wire right at the ignition switch, but done very poorly. I used a port on the fuse box but it would not start until a RELEASED the key... wierd... probably because I used an accessory port on the fuse box. It would turn over for ever but once I released the key, it started up. I changed that pretty quick. Now I am using a different key activated port on the fuse box that just says IGN going direct to the coil, and it is working fine. Coming from the ignition switch I would think is best because when you turn the switch off you are killng the circut right there at the source. Oh, I don't have a fuse on mine either I wouldn't worry about that other wire too.

I think if you verify you have HEI first, verify your vacuum, then verify you've got a good gauge wire going direct from the coil to a hot terminal on the box or the ignition switch, you can move on to other possibilities.

Looking at your actual symptoms again:

What about air delivery to the engine? Make sure you have a clean air filter and you can also zip tie your choke plate open in case it is closing on you while you drive.

You have the dizzy stabbed right so no worries there. You can also try advancing it more and more until it lopes when you start it, and/or it clatters on acceleration, then back it down. If it is too retarded that could be an issue. I had to resab mine also because of the same reason as you on mine Oh and my HEI coil doesn't have a ground Just the hot wire, and the harness to the distributor.
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Last edited by 2bits; 07-11-2007 at 06:41 PM.
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Old 07-11-2007, 07:00 PM   #9
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Re: HEI FAQ Questions/Clarifications... wordy too!

Just did an hei upgrade and the only problem I ran into was running the 12v wire to the fuse panel. I used an unfused terminal (although I did attach an inline fuse between the panel and the dizzy) checked key off- no juice.. checked key on- 12.something volts.. good right? WRONG.. my problem was I wasnt getting 12v WHILE CRANKING. It drove me nuts I checked everything 25 times. I said screw it- tapped into my Pink ign wire and it fired up RIGHT UP!! Just something to check if your having problems.

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Old 07-11-2007, 08:24 PM   #10
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Re: HEI FAQ Questions/Clarifications... wordy too!

Mine is a 30 amp blade type.
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Old 07-12-2007, 07:06 PM   #11
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Re: HEI FAQ Questions/Clarifications... wordy too!

Just listening to the behavior it exhibits on the highway, I'd suspect either

(a) the vacuum or centrifugal advance mechanisms aren't working or aren't hooked up
(b) the control module or the pickup coil isn't working correctly
(c) not getting enough voltage to the B+ side of the coil.
(d) bad coil or high voltage "leak"
(e) The fuel filter(s) need replacing
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Old 07-12-2007, 07:36 PM   #12
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Re: HEI FAQ Questions/Clarifications... wordy too!

Fuel Filter, good idea!
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Old 07-13-2007, 08:53 AM   #13
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Re: HEI FAQ Questions/Clarifications... wordy too!

New fuel filter. I just haven't been able to get back to the truck - had to spend the week chasing down some stuff for the boat. I will update this when I can get back at it (hopefully, mid next week).

Anyone know what I'd be looking for to swap a couple '72 318's (yeah, mopar) over to HEI? They are in my boat and run sweet but I don't want to be broke down on the water either when the points finally give out.
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Old 07-13-2007, 10:31 AM   #14
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Re: HEI FAQ Questions/Clarifications... wordy too!

Chunk that HEI junk and put the original distr. back in.
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Old 11-07-2007, 10:07 PM   #15
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Re: HEI FAQ Questions/Clarifications... wordy too!

Just got my HEI today and had no problems removing the old one, but now I cannot get the new one in. It stops about 1/8 of a inch from being seated. It engages the gears and the rotor turns but I cannot get it to seat. Any ideas?
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Old 11-07-2007, 10:21 PM   #16
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Re: HEI FAQ Questions/Clarifications... wordy too!

Quote:
Originally Posted by imholte View Post
Just got my HEI today and had no problems removing the old one, but now I cannot get the new one in. It stops about 1/8 of a inch from being seated. It engages the gears and the rotor turns but I cannot get it to seat. Any ideas?
You need to line the oil pump shaft up with the distributor gear.Look at the bottom of the gear there should be a little bar.This needs to line up with the oil pump.So just stick a large flat head screwdriver in the hole in the mainfold and turn the oil pump shaft until it seats
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Old 11-07-2007, 11:05 PM   #17
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Re: HEI FAQ Questions/Clarifications... wordy too!

RedHed69; "
Quote:
my problem was I wasnt getting 12v WHILE CRANKING.
I don't think you will ever get 12 volts WHILE cranking.The whole system goes down to something like 9 volts.
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Old 11-08-2007, 12:25 AM   #18
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Re: HEI FAQ Questions/Clarifications... wordy too!

Quote:
Originally Posted by cory321 View Post
You need to line the oil pump shaft up with the distributor gear.Look at the bottom of the gear there should be a little bar.This needs to line up with the oil pump.So just stick a large flat head screwdriver in the hole in the mainfold and turn the oil pump shaft until it seats
Thanks for the info....love this place
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Old 11-08-2007, 12:47 AM   #19
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Re: HEI FAQ Questions/Clarifications... wordy too!

Ok you have replaced the fuel filter and this problem has come up. I think you put the fuel filter in backwards. I did this once and it did the same thing as you are having a problem with. At 50 MPH you run out of power. You are running out of gas! The gas can not flow thru the filter backwards.
Check it out.
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Old 11-08-2007, 12:20 PM   #20
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Re: HEI FAQ Questions/Clarifications... wordy too!

Actually, I got mine squared away back in July - I had another setup and I pulled the vacuum module off of it and swapped it in - spun the tire three times just trying to get out of my driveway ('course, it's dirt) - runs beautifully! - only problem now, I keep trying/wanting to shift into 4th.....but there is no 4th....
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Old 11-12-2007, 05:58 PM   #21
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Re: HEI FAQ Questions/Clarifications... wordy too!

On the instructions for the HEI distributor it says to place plug wires in the same places, with #1 wire going to front passenger side terminal of distributor, but in my Haynes manual it has #1 plug wire to go to front drivers side terminal of distributor. I am unsure of of which terminal on my HEI does the #1 plug wire go?
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Old 11-12-2007, 06:24 PM   #22
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Re: HEI FAQ Questions/Clarifications... wordy too!

Quote:
Originally Posted by imholte View Post
On the instructions for the HEI distributor it says to place plug wires in the same places, with #1 wire going to front passenger side terminal of distributor, but in my Haynes manual it has #1 plug wire to go to front drivers side terminal of distributor. I am unsure of of which terminal on my HEI does the #1 plug wire go?
Bump the starter until you align the timing mark on the harmonic balancer at 0 degrees top dead center, then pull the distrib cap and look at where the rotor button is pointing. (Usually it's pointing toward the driver's side headlight, or is pointing 180 degrees (exactly opposite) to that headlight.) Wherever the rotor contact is, then that's where you want to attach your #1 plug wire.

If it's a V8, then follow with wire #'s 8,4,3,6,5,7 and 2 in a clockwise direction.
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Old 11-12-2007, 08:00 PM   #23
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Re: HEI FAQ Questions/Clarifications... wordy too!

Thanks for the info, got it running, and the idle is much smoother..need to try it out on the road to see if there is any performance gains, but it does start easier too.
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