Align Boring the Crankcase, Help educate this amateur... Options

[stephenaki]

OK, I understand the reason WHY you align bore the case, got it. My question with the 914 case is bearing selection after it is done.

Now, rebuilding my MG engine and selecting bearings was easy, measure the journals and choose the size needed. The 914 case however has a set on the journal and a set on the case.

If I have to align bore the case is there a special consideration on bearing selection or do I just measure journals and get a bearing set that accounts for the difference based on balancing of the crank.

May be an obvious question to some but I am confused and want to make sure I rebuild the engine correctly and order the right parts.

[dbgriffith75]

think my confusion is based on the fact that one set of bearings stays on the case and the others are on the actual crank. I believe the responses have answered my question and I will have the case checked for alignment once I get it completely cleaned up.

That doesn't sound right. There should only be one set of shell (halved/case) bearings for the crank and the cam. If one or both is undersized for the bore, you should just be able to measure the journals and buy corrected bearings.

Did you have the crank and/or cam ground down? Because that should be the only reason you need to buy oversized bearings, and the machine shop that did the work should be able to tell you what size bearings you need.

Pics would be useful if you can provide them to give us a better idea of what you're talking about.