Four speed input shaft troubles

[RemCharger]

Done deal. I made a call to a friend and he said I would be fine. So, I started with a 3/16 and ended with a 7/8. There is a lot of sizes between those two. I went up one size at a time. I measured the 69 depth and it is 2 1/4" deep by my tape. I drilled my '70 to 2 3/8". This process took me a couple hours but was well worth it. I am very happy that I won't have to cut the input shaft of the transmission.

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Wow. 20 bits? Must have been good ones?

 

[gdrill]

I took my time and it worked well. I would not say they are the highest quality, but they were not the cheapest either. It is not that much to drill so it wasn't that bad.

 

[69-73RR]

If someone could post a video of hand drilling out a crank at home ,I'd enjoy watching it. I wimped out and chopped the 1/2" off.
Can always buy a new input shaft.

Correct way would be to drill and ream a couple of thousandths undersize for correct bushing length for better shaft support and longer wear of bushing.
Most just cut shaft off and they seem to work okay. Just make sure shaft does not bottom out and put pressure on input shaft. I guess it depends on how much you will hammer / abuse the car. The 73 roadrunner 440, I'm doing, had shaft cut off and so far it works great. It's not a hemi trans.

 

[Scott Kiger]

Success!

 

[Krooser]

Well they did drill them from factory so it can't be that hard. Pun intended.

It's heat treated but not hardened...

 

[mopar 3 B]

Correct way would be to drill and ream a couple of thousandths undersize for correct bushing length for better shaft support and longer wear of bushing.
Most just cut shaft off and they seem to work okay. Just make sure shaft does not bottom out and put pressure on input shaft. I guess it depends on how much you will hammer / abuse the car. The 73 roadrunner 440, I'm doing, had shaft cut off and so far it works great. It's not a hemi trans.

Yea, like I'm going to cut the shaft off on my hemi trans.

 

[dvw]

I've balanced more than a few cranks. You always have to drill holes in them. Many times using a 3/4" bit with no pilot hole. I wouldn't say the material even on 4340 race canks drills that tough.
Doug

 

[Cranky]

If someone could post a video of hand drilling out a crank at home ,I'd enjoy watching it. I wimped out and chopped the 1/2" off.
Can always buy a new input shaft.

I have a lathe so drilling a crank at home is very easy

 

[rmchrgr]

Success!

How'd you do it?

 

[Scott Kiger]

How'd you do it?

Adter measuring a few times I cut 1/2” off the input and put a bevel back on it.

 

[rmchrgr]

Adter measuring a few times I cut 1/2” off the input and put a bevel back on it.

Easy-peasy, right?

Now go bang some gears!