Flathead to Slant 6 distributor conversion...

[thrashingcows]

Well I'm beginning to get my motor ready for the re/re in the old Desoto. I'm working on a new remote oil filter, converting to a 12V Chrysler Alternator system and converting the Flat 6 dizzy to a 80's electronic ignition slant 6 dizzy.

I have acquired all the parts to convert the dizzy, and tore everything down this evening. Now I have a couple questions for those who have done this conversion.

When you swap over the main shafts, do I swap over the more modern weights and springs, or keep the originals? Just wondering if the mechanical advance would be similar or not?

I will post up pics and info as I go along so other can benefit from my trials and errors.

[Plymouthy Adams]

anxious to hear how the distributor "shaft" swap is going to work..rotor for one..rotor button another..

[Frank Elder]

TC, not sure at all on the dimmensions, but why not have the /6 dizzy shaft tooled and fitted for the L-head.........don't think you actually "need" the old dizzy for anything but taking measurements off of.

[Plymouthy Adams]

Exactly Frankie...splice the lower end of the shaft..turn the base diameter and use the same distributor clamp and base adj as the stocker...

[55 Fargo]

Yes, the slant 6 distributors being used by a few Guys up here, a matter of some modding and machining the slant 6 diz to fit, my plan is to to also add this to the truck engine....

[greg g]

Swap the flattie drive tang, swap the hold down bracket from the flattie to the slant . check out this thread from last year.

Found it by searching google images for slant 6 dist.

http://www430.pair.com/p15d24/mopar_forum/showthread.php?t=20477

[thrashingcows]

Well if I had access to a lathe I could probably perform the conversion as Olddaddy did. But alas I don't, so I'm hoping to be able to do this without any major machining.

We'll see what happens. Guess I'll dive in head first and see if I eventually come up for air.

[greg g]

did you investigate transfering the /6 internals into the flatty body? might be possible with just a breaker plate swap or transfering the reluctor and pickup onto the stock dizzy.

[Plymouthy Adams]

be carefully..you might just be diving into the shallow end..

[thrashingcows]

Well it's done...I combined the two and I think it might work?

Anyway here's a step by step on how I did it.

Here they are side by side...

Now torn down...

[Plymouthy Adams]

don't see the finished product..did you lose a picture?

[thrashingcows]

I had a wee bit of a time getting the lower collar off the flatty distributor. The pin would not move...I tried heat, penetrating fluid etc. SO eventually I had to hack it off with my dremel and a hacksaw.

Here you can see how similar the two main shafts are.

The main difference...other then the distributor drive portion...was in the mounting for the mechanical advance weights. The flatty weights use a smaller mounting lug on the main shaft plate then the slant 6 one does. So you can't swap them. I weighed the weights and they were all 55g, so the only difference would be in the springs and when they would come in.

So I cleaned up the original flatty weights and springs, lubed them up and re-installed.

[thrashingcows]

So now came the hard part. The shaft bore on the flatty distributor, the part that runs down in to the motor, was 1.060". The Slant 6 dizzy bore was 1.090. SO I had 30 thou I had to remove. Well I don't have a lathe, or access to one so I did it the old fashion way....sand paper, micrometer and a couple hours.

I did the hard cutting with some 60 grit band saw paper and then used small, varying size strips of 100 grit to slowly polish it down to the right size.

Few pics...

And all done...

[thrashingcows]

Here you can see the two bushings that run between the wreights. The one on the right is the flatty, the left is the slanty. You will need to use the slanty one so when the top plate goes on all your clearances will be right.

There is a bushing/washer that runs on the bottom of the plate, between the plate and the distributor housing itself. The flatty shaft/plate junction has a slight lip so it runs the bushing on the right. I tried using it but the collar would not allow the shaft to drop down far enough to get the collar on the lower section of the distributor. SO I re-installed the original slanty one, on the flathead shaft. Not a perfect fit but should be OK I hope....

Now in slides the shaft...lubed it up good.

[thrashingcows]

Since I destroyed the original collar from the flatty I had to use the slant 6 lower collar. It wasn't a perfect fit. The shaft center lines did not match up. I had to find a drill bit just a hair smaller then the shaft through the distributor shaft and then drill through. Once that was done it was tap the roll pin into place.

Then cleaned up the original flatty mounting plate and installed. Not sure of the reasoning behind the timing marks plate that was on there, but I did not re-install it.

[thrashingcows]

Then it was re-install the vacuum advance, top plate assembly and all is done...

I hope all works properly when I finally get my motor installed into Ol' Fernando. Will definitely give an update when i do.

[greg g]

Thanks for posting, looks good.

[Plymouthy Adams]

I jumped the gun on asking for a final picture..did not realized you had just started a whole series of picture posts..you did a very in depth job of your step by step..good reading for the forum..very informative. Thanks..

[oldodge41]

Looks great. Thanks for posting that info with all the pictures.

[Don Coatney]

Great job! The slant 6 drive gear appears larger than the positioning shank. Will it fit down the hole in the engine block? How does the advance curve (both mechanical and vacuum) compair to the original?

[Plymouthy Adams]

Don..I looked it up once and saw no major difference..couple degree at most at any given point...as he used the flathead weights and springs..the curve should still be that of the flattie..best of both worlds..

[OldDad67]

Brian I'm impressed with all your hard work, but will this preform any better than a Pertronics conversion? Seems like a lot of work which I can understand because I like to do some things out of the box as well. Just courious.

[Plymouthy Adams]

you can get parts to support this modifcation at any big box sotre and on the cheap compared to having to pay out the yang for a pertronix unit and be down until it arrives in the mail..this is the why and wherefore on my modified distributor..

[thrashingcows]

Brian I'm impressed with all your hard work, but will this preform any better than a Pertronics conversion? Seems like a lot of work which I can understand because I like to do some things out of the box as well. Just curious.

Thanks for the kind words Olddaddy and others....I think Tim sums it up well.

you can get parts to support this modification at any big box store and on the cheap compared to having to pay out the yang for a pertronix unit and be down until it arrives in the mail..this is the why and wherefore on my modified distributor..

Only other thing I'd add is I'm cheap, and my labor don't cost me anything. And yes I like to do things outside the box...just 'cuze...

[thrashingcows]

Great job! The slant 6 drive gear appears larger than the positioning shank. Will it fit down the hole in the engine block?

You know I never even checked that....just got back from the garage and the drive gear is 1.01...so should fit just fine. Thanks for the heads up though....