8&3/4 489 Cone Style Mod

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Ivoryk3ys78

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Trying to find an article from about 20 years ago or if anyone knows how to do the mod or what part was called for. My dad had modified one of our 489 cone style pumpkins from an article out of either Mopar Muscle or Mopar Action. He had the face machined like you would expect but it had you modify the springs. It told you to get a certain transmission spring and you put it inside the other springs making a double spring so more pressure was applied.

It remember it worked great but he has looked all over and can't find it in the magazines he has saved and we have another one that is slipping and needs machined and shimmed and we want to do the spring mod as well.

If anyone remembers this that would be great.
 
Ivoryk3ys78 said:
It was more about adding more spring pressure and they felt adding this inner spring was a benefit. It has been many years ago I read it. Thank you for the link.
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Read the article. It tells you how to restore the spring pressure.
 
Back in the '80s I just used a grinding disc on one, and shimmed it, It worked great.
I'm sure machining it would be a lot more professional.
 
Thanks a lot. That's very helpful.

A couple of questions. Where do you get the shims to shim it and how do you know how much to get machined off?

Thanks
 
Ivoryk3ys78 said:
Thanks a lot. That's very helpful.

A couple of questions. Where do you get the shims to shim it and how do you know how much to get machined off?

Thanks
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I think I made a guess on how much to grind off based on the depth of the screw looking thread remaining on the cone.
The better side had just a few scrape marks on it so I didn't take much off that side.I then assembled it without springs to see how loose the spider gears were. I had access to some shims from a datsun dealer. Wish I knew what differential they were for! Anyway put it together a couple of times without springs till I'd reduced the slop in it without it binding. It was definitely the "cut and try" method of backyard engineering.
 
sccachallenger said:
Back in the '80s I just used a grinding disc on one, and shimmed it, It worked great.
I'm sure machining it would be a lot more professional.
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It does a nice job, but you know what? Your grinding was fine. It doesn't have to be precision.
 
Ivoryk3ys78 said:
Thanks a lot. That's very helpful.

A couple of questions. Where do you get the shims to shim it and how do you know how much to get machined off?

Thanks
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It depends. Sometimes the cones are badly grounded to the case. I've taken off about .070" on one I did a while back. I get the shims from Summit.
 
If you machine the cone you must shim the other side of it. I suppose you could stiffen up the spring pressure but its not necessary after rebuilding. The failure is not in the spring. Its when the cone wears and bottoms out.
 
MoparMike1974 said:
If you machine the cone you must shim the other side of it. I suppose you could stiffen up the spring pressure but its not necessary after rebuilding. The failure is not in the spring. Its when the cone wears and bottoms out.
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Yeah, we know all that. Did you even look at the link I posted?
 
RustyRatRod said:
It depends. Sometimes the cones are badly grounded to the case. I've taken off about .070" on one I did a while back. I get the shims from Summit.
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Thanks everyone this is very helpful. I have tried to find them on Summit. I think I am putting in the wrong keywords. Does anyone happen to have a link or know what it would be called on there?
 
Ivoryk3ys78 said:
Thanks everyone this is very helpful. I have tried to find them on Summit. I think I am putting in the wrong keywords. Does anyone happen to have a link or know what it would be called on there?[/QUOTE
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Hope someone supplies the part number. I think Steve Dulcich made his from some stainless sheets.
 
I read some thread said the shims were stock ford parts, but don't have number. I found some .060 stainless ones in Mac's Hardware, in the yellow specialty part drawers.
 
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