[PAUL K]

Originally Posted by poncho-mike

I have a 1974 SD455 4-spd car built in July 1974. It had about 75K miles on it when I got it back around 1985. I rebuilt the numbers matching engine due to a rear main leak. I was told the car had been driven very easily After tearing it down and checking the parts, I found the block had less than .001" wear in the bore and there was no wear on the crank. The rebuild was well documented (in 35mm photos), and I remember seeing the little marks in the fillets of the bearing surface. I asked my machinist what the marks were, and he told me it was a method of work hardening the fillet of the crank. The journals on my crank looked just like the first picture Tom posted.

I remember having some questions about the crank when I tore it down. My crank had 9799103 p/n cast into the crank. I remember seeing some paint marks on the crank, but I don't remember seeing a full p/n. At the time, I was confused because the parts list I had said an SD455 crank should have a different p/n. I discussed the crank with Nunzi or H-O on their tech line and told them about the rolled fillets, and they confirmed it was an original SD crank.

Any pictures of the "rolled fillets"?

The first picture Tom posted is the front counterweight with the painted on part number and the front main journal. Is that the picture you are seeing the marks in the radius?

[poncho-mike]

I'm pretty sure I have the pictures of the rebuild stashed away in boxes of old 35mm photos I took. I have boxes full of 35mm pictures I've taken over the years, but I've digitized very few of them.

Incidentally, I had access to a Cordax machine at work and took measurements of the crank, rods, and pistons. I was surprised at the accuracy of the machining on all of the parts.