HEI upgrade?

-
JRDART

JRDART

Owner "Poisoned Dart"
Joined
Jan 31, 2011
Messages
654
Reaction score
17
Location
Missouri
I saw a thread about this in another forum on slant 6's...I want to know everything about it, because all the instructions Ive seen to make one were poorly written and confusing.
 
what did you read that was confusing? all the threads i have read were well written and very helpful. i can tell you that is one of the best upgrades you can make.
 
I'll admit that diagram is not very well drawn. Here's some pointers

You MUST ground the HEI module using the two obvious mounting holes, and you MUST mount it to a flat area or separate plate for heat sink, using dielectric grease (heat conductive.) There are two plastic locator "tits" on the bottom, cut and file them off so the module sits nice and flat

Looking at the diagram, you are looking at the top (NON metallic side) of the HEI

Top left terminal hooks to coil positive, hooks to the dark blue "switched ignition" also called "ignition run" or IGN 1.

YOU MUST ALSO hook your brown used to be on the opposite side of the ballast to the coil pos. This brown is "ignition bypass" or IGN 2 and is hot when the key is twisted to start. Otherwise, you will NOT have ignition power when cranking the engine

(The dark blue "run" wire is cold during cranking)

Bottom left terminal hooks to coil neg. Also your tach if used.

The pickup coil is important. If your reverse those, it "moves" the timing so the spark is out of time with the rotor/ cap towers, also known as "rotor phasing."

So notice in the diagram, that.....

The top right terminal REGARDLESS OF COLOR hooks to the dist. shrouded female terminal on the dist. plug

The bottom right terminal hooks to the exposed male terminal on the dist. connector

4-pin_s.jpg


ALSO carefully check the reluctor gap at .008

AND check your engine off/ key on voltage at the coil positive. This should be very close to battery. If it's somewhat low, use a clip lead to "hot wire" the ignition directly from battery positive (big stud on the start relay) to coil positive until you get it fired.

On mine, I "cheated." I used common 1/4" push on female connectors even on the smaller pickup connector
 
One final Question...how do I check reluctor gap?...other than that it has been explained very clearly to where I can get it accomplished
 
oh and when bridgeing the ballast resistor its top to top and bottom to bottom on the plugs right?
 
Actually neither dark blue or brown are ever cold. If they were a backfire could result.
Owners who dont quite understand electrical will freak out if they go to the ignition switch connector and find approx. 7 volts on the brown wire while the engine is running.
 
oh and another thing is that on the stock coil it has a condenser attached to it...if I temporarily use my Accel coil for this upgrade do I need to use the condenser too? I dont see one in any of the mod instruction pictures.
 
oh and another thing is that on the stock coil it has a condenser attached to it...if I temporarily use my Accel coil for this upgrade do I need to use the condenser too? I dont see one in any of the mod instruction pictures
 
RedFish said:
Actually neither dark blue or brown are ever cold. If they were a backfire could result.
Owners who dont quite understand electrical will freak out if they go to the ignition switch connector and find approx. 7 volts on the brown wire while the engine is running.
Click to expand...

The 7 volts is feedback coming from the ballast. It doesn't do a thing as the switch contacts are open. How does this prevent backfire?

I don't know about "all years" but at the very least "some years," the dark blue most certainly goes cold when the key is in "start."
 
JRDART said:
oh and another thing is that on the stock coil it has a condenser attached to it...if I temporarily use my Accel coil for this upgrade do I need to use the condenser too? I dont see one in any of the mod instruction pictures
Click to expand...

The condenser should be hooked to the coil positive and it is there for radio noise suppression. Even if you don't have a radio it may be beneficial.

Radio noise is ALSO hash, noise, electrical spikes that can affect low level electronics -- like a breakerless pickup circuit!!
 
67Dart273 said:
The 7 volts is feedback coming from the ballast. It doesn't do a thing as the switch contacts are open. How does this prevent backfire?

I don't know about "all years" but at the very least "some years," the dark blue most certainly goes cold when the key is in "start."
Click to expand...

The dark blue gets voltage along with the coil from the brown wire in start too. Current will flow through the ballast resistor in either direction.
Ever turn ignition switch off and one again during run ? We use to blow the mufflers off school buses like that. LOL
So there never is even a split second between start and run when the ignition has no power, by design.
 
JRDART said:
One final Question...how do I check reluctor gap?...other than that it has been explained very clearly to where I can get it accomplished
Click to expand...

You need a .008" NON magnetic feeler gauge, in other words, brass. I just "ran into" a set of brass ones at O'Reilly's the other day when picking up a larger set to check my valves. The valve set had one brass one -- a 010, the wrong size. Just adjust the pickup coil just as you would points. Be sure to wiggle the shaft and look for play and check when you are "done" that it doesn't have so much wobble or play that the reluctor hits the pickup coil



JRDART said:
oh and when bridgeing the ballast resistor its top to top and bottom to bottom on the plugs right?
Click to expand...

No, the long way. One side does not matter, as it hooked only to the "box." The two you need to jumper is the one supplying "ignition run" (key in run) and "ignition bypass" (key in start). These are normally dark blue and brown. To be sure, unhook all four, turn the key to "run" and probe the connectors looking for power. The hot one is one you need to connect to.

Now see if you can ID the connector with brown, or try the other three one at a time. Twist the key to start, and the one that lights is the second one you need to connect.

The diagram below is not complete In this diagram, the dark blue "ignition run" is the top right terminal of the ballast. The brown "bypass" circuit IS NOT SHOWN and would connect to the bottom right of the ballast

So the top right and bottom right terminals of the ballast, in this diagram, are the ones to jumper

Ignition_System_5pin.jpg
 
my ballast resistor connectors are the single two spade connectors one on each end...so I need to jump the Ignition run to the ignition bypass right I.E. connect both terminals that light up to each other?
 
WOW! Thats awesome! I wondered how that worked. What exactly are the benefits of the 'HEI" over stock mopar elec. ign.?
 
HEI gives a hotter, longer-duration spark (for better ignition and more complete combustion) and eliminates the ballast resistor (which is a common failure point)
 
Ok so I pulled the HEI unit out of my 425 Cadillac v-8 dizzy. Got all the necessary items to do the Install. I have an Interview at a local body shop today so as soon as I get back I'm going to do the install including taking step by step pictures. I've heard nothing but good things about this mod so I've got a good feeling.
 
Ok so the HEI is a no go for today. I busted a fuel line I suspect and had to be towed home. As soon as I get the fuel to test my experiment Ill get the necessary steps up. Meanwhile if anyone wants to give it a go then feel free to put up an instruction thread before me lol
 
You must log in or register to reply here.
-

Back
Top