Which Hei Distributor To Choose

I pulled a 231 Odd-fire distributor today. The offset of the contact vs. an even-fire shaft is less then the width of the tip of the rotor. Highly unlikely that it would ever change the operation of the distributor. For some it may be better to just buy a reman odd-fire from Rocauto.com for about $120. For others this is definitely a viable option to convert an even-fire HEI to operate in an odd-fire motor if they find a good core in a wrecking yard. The odd-fire pickup coil can be bought for as little as a few dollars.

 

I just bought an odd fire 231 reman from rock auto as Daryl stated. I did nothing to it at all. It just works and that’s it.

I am interested on how to convert an even fire distributor to odd. Some pics and quick rundown on parts would be nice to see just for my own education.

I am sure with about 20 min of research I could figure it out, but why not post it here too?

There is a lot of info about fine tuning the vacuum advance and all sorts of things, fact is, i wouldn’t even notice probably. Runs fine as it came from rock auto.

 

Post 44

 

Daryl, that certainly not always true.
Apparently there were several versions of the odd fire HEI.
I'm not sure exactly how many .
Here's a rotor lobe pic from an odd fire HEI DR # 1110668
Shows factory "timing core" orientation in relation to "rotor tip"



Focker....
I just took a bunch of pics of the distributors that I have.
The early Jeep Prestolite IAT 4502, theJ eep DR 1110376 and Buick 1110668 distributors.
The first two are original points type distributors used by jeep.
I will consider putting together a comparison article for the various D-225 distributors.
For beginners one might be better off to show standard components and orientation before getting deep into non standard modifications.

For some applications these original jeep points type distributors have certain advantages over the HEI systems.

 

The larger diameter of the HEI was neccessary to keep the spark from internally arcing from one contact to another. The spark is that much hotter. Converting to an HEI is the easiest way to have nearly instant starts almost every time you turn the key.
-Donny

 

Many years ago (1970's in college) my daily driver was a 1964 cj5. It had a swapped in 231OF with the distributor shown in the middle of post 66 above. One day I was driving home from school with a buddy. we saw that an empty lot in our neghborhood flooded. I HAD to drive through the middle, spraying a wake of water. Barely made it home with a cracked dist cap. The correct cap was two days out as no parts store in Fresno had it. I drove the Jeep for two days with a SB chevy dist. cap that I had on hand. The rotor tip is so big, compared to a V8, i was able to mark the dist body and aline the plug wires in the new cap. With two empty holes in the V8 dist cap the Jeep ran fine. I only drove it to school and such, no off road, but it ran fine.
No experience with HEI in these engines but from my experience the rotor tip gives you a lot of flexablity.

 

Something else to look at in your research of converting even to odd hei dist. What I have found (so far) is the even fire cap location comes in 4 different locations. Meaning the dist base locator notch can be in one of four places. The odd fire dist base has the locator notch in one place only. That notch is to the right of the vacuum can about 1 inch. Anybody find any different? I would like to see a picture of it for my records.

 

This is the even fire lobe location after removing the other 3 from the V6 even fire as per internet info instructions.

 

The difference is still within the width of the tip of the rotor. The picture that Ken posted is interesting as it is offset the other way compared to the one I pulled. This leads me to believe that the rotor phasing is even LESS important as it seems to make no difference at all.

 

Yes the rotor index notch on Walts even fire shown above is the same location as my odd fire rotor uses
But the timing core reluctor was ground off in notably different position than the odd fire timing core reluctor.


In this pic you can see my odd fire timing core reluctor and one of the indicators is stamped with a 1.


The odd fire #1 reluctor indicator lines up perfectly on to the wide "pole piece" indicator as shown below marked in blue...
Number one rotor positions are shown with red in the following pics.



Inside of HEI cap. Number one terminal is seen at 6:30 position.


And the rotor inside the HEI distributor cap is simultaneously pointing directly to the # 1 terminal.

 

This is the GM V6 even fire.

 

These two pics show the distributor location in an early D-225 timing cover.



HEI shaft going into hole...


HEI distributor body hits the manifold bolt.

 

The # 1 terminal on the cap is the red dot in your picture in post #74.

 

Walt I later had edited out that "not shown" and added more pics....

 

I see you did. Good show. You are doing great with the examples. It will help clear up a lot of mystery for some.

 

Here again this pic shows the HEI


It has 3 wires... black wire is ground


I need a coil cover for this distributor cap


This pic shows the "pole piece" in center of the distributor housing.
It's held on with 3 screws...


Top of rotor.
Not sure why that magic marker line is on there.


Shaft is installed showing the centrifugal flyweights


DR GM part number


That's most all of my HEI pics.
But still have lots of pics and info for the points type distributors.
Did I miss anything important ?