Thread: SBC Journal size

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Ok 2.10 is the rod size, if it's turned .010 that makes it a 2.09 right?
If that is correct can I take a large journal crank thats been turned to the limit and turn it down to 2.00 to fit a small journal block? My buddy is throwing away his used up 350 large jounal steel crank, can I save it for a small journal block?

You're talking apples and oranges, but yeah why not. You wouldn't turn the mains down to 2.000" though. 2.000" was the small rod journal size, 2.100" is the large rod journal size. 2.300" was the small main journal size, 2.450 is the large main journal size. We turn 400 cranks with their 2.650" main journal size down to the smaller 2.450" (350) main journal size all the time to make a 383. I'm told it's a little different grinding the rod journals though because they are "clocked" at a certain position to supply oil at a certain point of shaft rotation. I never studied this at all and so cannot offer an explanation except I think when you grind the rod journal, you move the oil supply hole around on the journal away from the correct "clocking" position. It would seem a simple matter to me to do a little grinding with a small burr to open up the oil supply hole to the original position. Maybe another board member has more information for you. I want to learn about this too.