johnneilson
Well-known member
I do not know the heat treatment of the original cranks, what I can say is that after machining a few of them, they are consistent pretty much thru.
The cranks ground under-size down to 1.800 are fine, smaller don't know.
I can tell you from cross drilling thru for oiling the rods that there is no soft center. The chips are pretty consistent as you get down into the middle.
Now, I have drilled a couple aftermarket cranks, and they are soft in the middle like a candy bar.
Like anything else, changing the motor to perform better? has its consequences.
Anytime I build for over 100 HP, the crank is welded at the flange and chevy rear seal installed. This helps alleviate the crank from breaking the flange off.
John
The cranks ground under-size down to 1.800 are fine, smaller don't know.
I can tell you from cross drilling thru for oiling the rods that there is no soft center. The chips are pretty consistent as you get down into the middle.
Now, I have drilled a couple aftermarket cranks, and they are soft in the middle like a candy bar.
Like anything else, changing the motor to perform better? has its consequences.
Anytime I build for over 100 HP, the crank is welded at the flange and chevy rear seal installed. This helps alleviate the crank from breaking the flange off.
John