Align Boring Cases

PJMARKOW · 12-13-2003, 02:21 PM

I was just given the bad news from my machinist that my case is almost 0.010" out of spec, so will have to be align bored. The case is a 1977 930 aluminium one. Here in Australia there is no one that resizes these cases back to standard, so I will be forced to have it align bored and then use oversized main bearings, which I'am told may be hard to purchase. In Wayne's book, he states that these bearings are not ideal to use. Is this just because they are hard to obtain, or is there some other reason? My only other options would be to use another case, or as a last resort, ship it to Competition Engineering in the US, to have them machine it. Any thoughts regarding this would be much appreciated.

kwikt 911 · kwikt 911's Garage

If machined to O/S bearings. You can get them from a dealer or machine shop for around $300. I had Ollies do mine for around $450 total including bearings.

Kevin
72 911T/E

afterburn 549 · 12-14-2003, 11:57 AM

The ez thing is O.S. bngs. if you go the other way it gets a lot more complex and $$$
t.m.o.

Wayne 962 · Wayne 962's Garage

Ship it to Walt - he charges $495 for the resize, and he will be able to give you a 2nd opinion. These aluminum cases generally do not require it...

-Wayne

Wayne 962 · Wayne 962's Garage

Your case uses the 2.7 Oversized bearings which can be $400-$500 by themselves...

-Wayne

PJMARKOW · 12-15-2003, 01:52 AM

Thanks for your advice but shipping to alt from Australia may be a bit expensive. After making some enquiries here I have found out that the Porsche Centre Melbourne align bore cases here, so I will ship the case there for them to check and align bore if needed. They say they can supply bearings, but I they haven't given me a price yet. My crank checks out ok, so I will need oversized std mains.