HEI conversion help and pictures thread

[Zervun]

Hey all, I need help with my HEI conversion.

Fairly new here and have some issues and want to give back as I've been a lurker here for over a year. Incidently I should have probably titled this as "need help" not help in the subject oh well can't change it now

I need help with my HEI conversion and I'm taking a bunch of pictures so this will hopefully help someone in the future. Most of the readme I've found so far don't have pictures

So this last year I bought a 74' and am in the process of getting it running better/restoring. It's got a 350/th350 and a edelbrock 1902 (quadrajet) that looks pretty new.

Engine and Tranny are less than 20k rebuilt. It's been randomly studdering/loss of power at completely random times. If I throw it in neutral it sometimes makes it better.

I think unrelated but gas guage is jumping around - I'm guessing bad ground. I also have a leaking gas hose that goes to the gas tank (drips a little when filling up. It's 28 degrees out in Portland right now and don't want to drop it right now. I have almost run it dry, so that next fill up I'll know what size tank is in my 74, so I will probably do all at once - gas tank drop, gas tank hoses replace, in tank fuel sensor replacement (need to know the size of my tank first), check the tank ground/replace.

Things I have done so far for the studdering:

• replace full pump - almost **** myself it was only 19 bucks
• replaced fuel filter on quadrajet
• replaced gas cap
• put heet in
• replaced PVC
• replaced in air cleaner PVC filter or whatever the hell it is
• replaced air cleaner filter

I figured at this point I should just convert it to HEI. I've read a ton on the conversions and think I had it down, until I looked at my truck.

From what I have read

• replace dist with an HEI dist
• replace 12v hot wire from dist to fuse block as it has a resistor in
• remove the starter hot wire that gives full 12v on startup as it is redundant when you have full 12v to fuse block on IGN
• .45 gap for HEI, AC delco
• Start tuning at 8* degrees

This is from posts and here http://www.oldengine.org/unfaq/hei.htm

What I think I have figured out so far

• baby poop brown off the back of the coil is the starter full 12v hot - can possibly just cut/cap it off for the moment until I can take whole thing off
• stripper red off the coil is the positive that maybe has the resistor in it but I'm confused that it goes into a harness. From what I've read the resistor wire going into the firewall block is a white wire with a somewhat material wrap around that, I don't have that (3 spot on diagrams below)
• Orange is the ground wire? Who uses orange as the ground wire?
• I should have looked at the top of the coil for + and - but beers were calling and I forgot

In summary to convert it I think I need to:

1. Remove both wires from coil, coil, and harness
2. wrap tape around harness because I'm lazy, leave the ground from harness because I don't want to deal with it right now
3. cut brown wire and cap it/wrap it with electrical tape
4. Since I can't figure out firewall pass through just ignore it
5. Wire 10/12 guage red wire from new HEI dizzy bat through firewall and into a spare IGN slot I have
6. Time it and done

Pictures are following

Coil setup showing the wires


Mystery brown wire


Harness


Wiring schematic - I'm thinking that maybe the 20 P/B is the resistor wire that is actually the red from the coil that goes into the harness and hookes into 3


Magical 20 P/B -3 same as above


I think the resistor wire is in the top block not the bottom, but it doesn't specify anywhere


I'd also not like to thank the idiot that put the dizzy on the rear of the engine on chevys - I'm worried my HEI from summit that I got won't fit until I get the ORD 1" body lift I got in.

 

[blazer74]

Old dizzy, coil and its wires gone. New dizzy, new 10/12 wire to full 12 volt ign fused source. Fuse box spare ign terminal fine. 8-10 Deg should be fine. R44/R45 plugs and hei wires. (.045 gap)

After u do that if u still have stumbling look at the carb, 1402 EDL may be a tuned a little too much for a stock 350 if that's what u have.

Fuel gage ground wire at tank or sender wire runs up right frame rail and crosses over into engine harness near starter( mines that way). Last is in the cluster.


Never mind about the 1402 carb I was thinking of the 1910EDL

 

[airemdwn]

Are you running an MSD 6A or similar ignition box?

 

[Zervun]

Are you running an MSD 6A or similar ignition box?

Nope don't think so unless he hid it somewhere that isn't easily seen. I'll poke around tonight.

 

[Zervun]

Old dizzy, coil and its wires gone. New dizzy, new 10/12 wire to full 12 volt ign fused source. Fuse box spare ign terminal fine. 8-10 Deg should be fine. R44/R45 plugs and hei wires. (.045 gap)

After u do that if u still have stumbling look at the carb, 1402 EDL may be a tuned a little too much for a stock 350 if that's what u have.

Fuel gage ground wire at tank or sender wire runs up right frame rail and crosses over into engine harness near starter( mines that way). Last is in the cluster.


Never mind about the 1402 carb I was thinking of the 1910EDL

It's a 1902 not a 1402 (not sure that matters). I popped open my master cylinder as it looks to be leaking a little and it was down on fluid so I'm wondering if I have a vacuum leak that is causing issues as well.

 

[blazer74]

1902 74-78 divorced choke 350-454 Eng. should be fine assuming its in stock form. They quit making edl q jets about 10 years ago.

 

[byggyns]

Someone correct me if I'm wrong, but I thought that the points distributors only had one wire going into them, not 3. The one wire should connect the points to the ground side of the coil. When the points close, the field collapses and fires the coil.

So, looking at the pictures makes me think someone put an aftermarket electronic distributor in your truck, or did a points conversion.

I will tell you that I haven't even looked at a points distributor for a v8 in 10 years, so I could certainly be incorrect.

I hope I haven't thoroughly confused everyone.

 

[chulisohombre]

That dizzy isn't a stock one. Mine only had one wire coming from points to the neg on coil to fire it. That looks like a DUI maybe something else but it uses a pickup similar to hei and could have been converted from stock. It has msd coil so it may have been modes and isn't working correct. Hei is simple. Just run a wire from the inside acc plug and female spade connector on both ends to yhe hèi. Tdc on engine and rotor on the right spot. Fire it and time it. Mine fit in my 72 without modding the firewall but its only about a 1/4 inch from it.

 

[82355]

Pop your distributor cap off and take a picture of what is inside of there.

Martin

 

[Zervun]

Pop your distributor cap off and take a picture of what is inside of there.

Martin

Sorry for the late replies, been below freezing out lately and haven't had the chance to work on it. I'll have pictures of popping the cap off here in the next few days.