Hot Rods Desoto crank mods,,,oiling passages and rear flange?

i have been looking at the oil journals in my crank,,,they look awfully small.
Mic about.180,,,,or a few thousandth less?
I seem to remember reading a few years ago that it is recommended to increase the size somewhat. I was thinking similar to SBC size or close?
Good idea. ? If so,,,where would be a good place to buy a quality drill bit,,that is extended length?

Also,,,it is recommended to tap rear flange to 1/2 inch size,,,,good idea.
I was thinking that I should still use longer bolts,,and nuts on the back side.
The reason being that my adapter and the flywheel spacer would add side stress to the bolts.
Am I overthinking this?
I just want to be safe,,,a flywheel coming loose is not something I want to happen!

Tommy

 

On the 7/16 20 bolts, I left my 330 alone and I am running a similar adapter. Needed 1 1/2" long bolts. Hot Heads said they do this all day long under hard conditions and not had any issues. I hope that is right cause its too late now to change things.

 

Doesn't your crankshaft flange have a pilot or dowel pins to locate the flywheel? If so, your adapter should have a recess for the pilot or holes for dowel pins and a similar pilot/dowell pin on the opposite side to locate the flywheel. Recess/dowell holes and pilot/dowell holes should be concentric within .001-.002 tir.
Therefore, there will be no side loads on the bolts. Most engineers avoid bolts in shear whenever possible and almost always avoid bolts as precision locating devices.
Good luck.
Farmalldan

 

No,,,old Hemi cranks have 8 bolt holes and no registers for the flywheel.
The flywheel actually had a recess milled out in the center,,,which let the flywheel register off of the o.d. Of the rear crank flange.
Imagine,,just a flat flange on the rear of the crankshaft.
The new adapter has the old flange pattern on the back side and the new register on the front side to locate a modern flywheel.

Tommy

 

Does anyone have any experience opening the oil journals in a crankshaft?
I am needing a quality bit with extra length?
Any suggestions would be appreciated.

Tommy