Were 68 440 magnums drilled for 4 speed?

[tallhair]

Were 68 440 magnums drilled for 4 speed?

I’ve always thought they were but just checking. I have a 68 440 Magnum and it has a pilot hole but wonder if it will accept a stock 4 speed bushing and if it’s deep enough for an uncut 833 input shaft.

It’s on an engine stand now, but before I put it on my pinky fit in pretty deep, prior to putting it on the stand. I can’t actually measure now that it’s on the stand.

Thanks !

 

[1968rt]

Providing its the original 68 crank, its deep enough. Just has to be honed out a few thousandths and a pilot bearing pressed in or you can go the modern route.

 

[IQ52]

I've found the forged cranks drilled to the standard bushing size and that stupid one that is just a little smaller outside diameter. Either way the input shaft clears the crank with no bushing. I mostly leave the bushing out now and just use the roller bearing that fits into the converter hub recess of the crank. Just like above.

 

[tallhair]

Providing its the original 68 crank, its deep enough. Just has to be honed out a few thousandths and a pilot bearing pressed in or you can go the modern route.
View attachment 1051762

Thanks much.

I've found the forged cranks drilled to the standard bushing size and that stupid one that is just a little smaller outside diameter. Either way the input shaft clears the crank with no bushing. I mostly leave the bushing out now and just use the roller bearing that fits into the converter hub recess of the crank. Just like above.

Thanks IQ. Do you do this for simplicity or because it’s superior to the original bushing?

 

[Daves69]

FWIW,
This '68 auto crank I have has the necessary depth for an uncut input shaft but the bore diameter where the bushing is pressed into is only about .890" diameter.

Brewer's posted a diagram here that may be of use.........
https://www.forabodiesonly.com/mopar/threads/pilot-bushing-help.428204/#post-1972398631

 

[IQ52]

Thanks much.



Thanks IQ. Do you do this for simplicity or because it’s superior to the original bushing?

Boy is it simple and it hasn't failed on my 848 HP 500" wedge. Plus if you drill and tap the outer heavy ring 180 degrees apart you can easily use two push bolts to remove it.

 

[hunt2elk]

Here is a pic showing the specs so you can measure what you have.

 

[Daves69]

Make sure you indicate the bell in as well.

 

[tallhair]

Make sure you indicate the bell in as well.

Do you mean to verify the bell housing is centered on the crank IAW factory specs? Using offset dowel to bring in spec?

Or something else?

 

[tallhair]

Plus if you drill and tap the outer heavy ring 180 degrees apart you can easily use two push bolts to remove it.

Thanks for all the help. I’m having trouble picturing what you mean. Would something like a puller also need to be used?

 

[Daves69]

Do you mean to verify the bell housing is centered on the crank IAW factory specs? Using offset dowel to bring in spec?...

Yes sir! And shims if necessary for the bell face runout .

The drill an tap idea of the pilot bearing housing is to provide an easy means of removal when necessary. With tapped holes all the way through you just use a couple bolts to work it out.

 

[RemCharger]

To truthfully answer the question; All 440 magnums with a 4 speed, were properly drilled/honed for a 4 speed input shaft bushing. beyond that is all conjecture .

 

[bandit67]

To truthfully answer the question; All 440 magnums with a 4 speed, were properly drilled/honed for a 4 speed input shaft bushing. beyond that is all conjecture .

Ram, my understanding is that all 68-72 factory 440 steel cranks were ALL drilled for pilot bushings......true or not true.....thanks..

 

[RemCharger]

I would lean towards not true. Theres a 68 and a 72 at my shop I will check on, but fairly certain they aren't drilled.

 

[tallhair]

To truthfully answer the question; All 440 magnums with a 4 speed, were properly drilled/honed for a 4 speed input shaft bushing. beyond that is all conjecture .

If the crank isn’t drilled what is the depth?

 

[dadsbee]

If the crank isn’t drilled what is the depth?

hunt2elk showed you that above...

 

[tallhair]

That’s the depth required.

I asked for cranks that are not drilled. How deep is any hole, if any past torque converter hole?

Am I missing something?

 

[dadsbee]

Ah.. I see what I read wrong. They are all drilled, they just aren't finish drilled and guaranteed centered. If it's not finished for a manual pilot bearing you generally need to cut about 5/8" off the input shaft and use a roller bearing... or the undersize OD pilot bushing if you want to trust that the rough hole is centered.

 

[tallhair]

I can get an ink pin almost 2.5” in. ~ 2 and 7/16 from the lip that surrounds the hole. About 1 7/8 Deep from the larger hole for the converter hub to bottom.

it’s drilled with a cone at the end.

if it’s deep enough I’ll just use the new large bearing.

 

[Daves69]

My old 383 auto crank had about a .100" deep center drilled into it if that helps.
Below depicts my '68 auto crank in the previous picture. 2.120"......