Rod Bearing Clearances

[Juddidiah]

I come looking for knowledge.

#8 rod bearing is down ~.036"-.042", which is in tolerance for out of round ( according to the manual)
But with a  .010" over sized bearing set, the clearances are down to ~.009", the book calls for .0013-.0035"
I'm going to sand down the rod bearing journal so that a .020" bearing fits to tighter tolerances. Suggestions?
Obviously it's not the greatest design, but how bad of a deal is it to have #7 rod bearing a standard, and #8 a .020" oversized?
There isn't any mobilel crankshaft turning machine that could turn down this one journal? Is there?

Thanks as always for your input!

[IROCnRoll]

I'll say that I've never heard that been done before. They have steel cranks fro as low as 299 a bit more for 399. Also how do you inntend to get the journal perfectly round. I have a couple of 350 1 piece std/std cranks I'll give you one. I don't have any other LT1 stuff sold it all. Ebay has some LT1 stroker kits for $1500-$1700. That ae forged. If I can help you in any way let me know.

[IROCnRoll]

Also I've been thinking more about this. Another the step that you'd have has probably been caused by the pounding of the rod bearing. I don't think it'll work for becuse you are supposed to have piston side clearance of about .018-.020. If that step is in the journal maybe it does maybe it doesn't have enough to allow for side thrusting of the rod.

[gofast]

Realistically, it doesn't matter if #8 is .020 oversized and the rest are standard. What's important is that they are all round and within spec in regards to their given bearing size. You'll just have to remember that #8 is 'special'. As it was mentioned, you won't be able to sand that journal perfectly round, so I'd suggest taking it to get it ground at a machine shop. Getting a new crank however, would be another option.

[Tom Albritton]

Your best bet to fix your problem correctly would be to have the crank checked for runout and to regrind the crank to properly specifications. You should not attempt to sand or grind on your individual rod to attempt to achieve proper clearence. You will not be able to get it round which could have catastrophic consequences. I would take your crank and rods to Earl at Clegg's or Dave at Pro Machine, describe your problem and allow the professionals to repair it properly and supply you with the correct bearings. You might have a problem with your block too like a misaligned bearing cap or ?

[Juddidiah]

Thank you all for your input. I realize that everyone is talking about properly fixing this problem. I am trying to sell the car, and i am straight forward with the problem, but i am trying to involve as few of unneeded dollars as possible to get it to a better running state. I really don't have any patience to pull the motor for the 4th time. After taking some time to address the issue, the journal is .040" out of round, spec is .010". I realize that there just aren't any good options. Thanks for your input.