1st, please don't ask why you would want to do that questions!

The trick is 4 spacers inserted on the sides of the thrust bearing and using a forged crank thrust bearing.
Second, it looks pretty simple.
2 spacers made from aluminum, thrust bearing location, one on either side.
One .060, one .090.
They look like this, but need 4 spacers total, top and bottom.

????
Dave, Mark, others???

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Hyper_pak

Any specific reason to make the spacers out of aluminum?
They would be easier to make in steel.

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No steel is fine also.
The pictures are from youtube, they used aluminum.

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Hyper_pak

I'm going to ask Why. To me it doesn't make any sense. I could see trying to put a cast crank into the forged crank block. Narrower bearing for less drag, and lighter crank for faster/higher revving.
Please splain your reasoning to me.

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 225 nitrous
64 Valiant Signet
64 Valiant 4dr 170

I second that

You know he could tell you but you know he'd have to kill you, so it is better that you don't know!

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

I would disagree. Aluminum is much easier to turn but steel would be better.

It will cost more to make these than a crank or different block. I know you didn't ask for this info but thought I would put it out there. 30+ years of manufacturing here.

If you used steel they can be made very precisely flat and parallel on a surface grinder. That would yield a much better finished product and the machine work would be very straightforward even for an unsophisticated machine shop. It would not take any special skill or luck to make them very accurately. It would even be easy to 'adjust' the fit if it was a little too tight.


@hyper_pak - Instead of shims did you consider having the thrust surfaces on the crank welded and re-ground to fit the cast block thrust bearing?

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--> Check out my FI Turbo build <--
--> And the race truck build project <--
--> The Diesel Corvette <--

All they have to do is locate the trust bearings in the correct location.
I like the steel idea, it's would take the trust loads better.

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Hyper_pak

No don't want to weld and machine.
I just want a drop in solution.
If I had a design document I could get a shop to make them.
If.

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Hyper_pak

I seen a YouTube showing a magazine that did a forged crank into a cast crank block not long ago. And since, there has been questions as to why. I haven't seen anything answering that so far.

Thinking I didn't know what he was asking for. If it is flat I agree. My bad.

The Engine Power program used either a turbo or blower, don't remember right now.
So their reason was they wanted the strength of the forged crank for the higher power levels.
So there is one possible answer.

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Hyper_pak

80s cast crank block weighs typically 22-28 lbs less than a forged crank block. Both cranks are plenty strong unless you go beyond about 400 HP, then forged is your deal.

Lou

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Home of Slant6-powered fun machines

The cast crank is also lighter than the forged, and though I never could afford to have a toy that I could just let sit around and have to be trailered everywhere it went, only to come out a handful of weekends a year, it's been said that the cast crank is actually pretty robust also. If you're at power levels that you don't think the cast crank made for the cast block will work you're probably better off with a block made for the forged crank as well with it's wider bearing for more support.