Line Boring Source Needed

[John Weyand]

I have the engine for my C completely disassembled and learned from the machine shop that it's needs line bored, at least at the center main. The shop in Massillon, Ohio can do everything except the line boring. I would like to get it done somewhere close (within driving distance) but if necessary I will ship it to get it done (right). Perhaps there is a shop near Pittsburgh (about 90 minutes east of here) or towards Columbus, Oh. (It's a 912 motor.)

[David Jones]

John,
Call Larry's off road in Dayton. http://www.larrysoffroad.com/contactus555.html
Ron's Machine just up the road used to do VW line boring for them. If he is still in business he can do 356 engines. Same tool!

[Gerry McCarthy]

John:
It is more desirable to lap the face of the case halfs, then bore the case to standard. You must also rebore the flywheel seal seat, but, the standard O.D. bearings are less expensive, helping to offset the higher machine costs. In any case be SURE to have the correct bearings for the finished job in your hands BEFORE boring the case. Oversize bearings are very hard to come by. If you bore the case then can't find suitable bearings, you are OUT OF BUSINESS!

[John Weyand]

Dave, the case is a 912 so the main bearings are not all the same size. A VW shop usually can do only those cases with a uniform size throughout.
Gerry, the caveat you raise is exactly why I've posted here, I don't want to be seeking the holy grail just to get my engine back in operation.
Via email I got a referral for a shop in California and will pursue that lead tomorrow.
Thanks!

[Ron LaDow]

John:
It is more desirable to lap the face of the case halfs, then bore the case to standard.

Gerry, I know that's been the standard practice and it delivers good results, but I'm wondering why a .0005" cut on each half with a large facing mill cutter wouldn't give the same results at 1/10th the labor.

[Jacques Lefriant]

Hi John
the bearing OD is the same for #1,2,3
Hi All
if the price of line bore bearings is comparable to STD OD just lineboring is less work, but each case should be evaluated on its own and the shop doing the work should have the proper equipment and experience.
j

[Jacques Lefriant]

Hi another caveat VW shops are used to machining Magnesium cases. The Aluminum cases are harder to machine and VW shops mostly only do the later 65mm size.
j

[Martin Benade]

Is the option of cutting the case halves only for very slightly worn saddles? Ron's example only shrinks the width of the hole by 1/10 of the first oversize bearing diameter, before lineboring back to std. Also I would be leery of the VW shops who may just have the anybody-can-do-it electric drill-powered tool, instead of an actual machinist with the proper equipment.

[Brad Ripley]

IMHO, send your case to http://www.competitioneng.com/History.htm and get it done right -- enough said.

[Peter Boettcher]

John,

Brad has offered the very best advice, ship it to Walt at CE.
Speaking as a very satisfied customer.

Peter Boettcher
Cincinnati, OH
Minus 12 this morning!

[Steve Harrison]

Here is another option, also from some advice from Brad, in an earlier thread on connecting rods machining.
http://www.olliesmachine.com/

They have a price list and services offered page.

[John Weyand]

I very much appreciate the info. I have sent a message to C E in CA and will await Walt's reply. What I have found is that the measurements are No 1 2.372 in
No 2 2.374 in
No 3 2.373 in
In Harry's "Secrets of the Inner Circle" he gives the acceptable range for standard case size as 2.3715 to 2.3719 in.

[Jacques Lefriant]

John
#1 main is 50mm do you have the numbers backwards?
j

[John Weyand]

J, you are correct.

[Gerry McCarthy]

Jacques: It is the number 4 bearing that is 50mm. The flywheel main is number 1
Ron: It is most unlikely that the case half will be flat within anything like .0005, so that lapping each half by .001-2, then bringing the bores to the exact size is the way to go. What you are attempting would require unreal level of accuracy, and, the bore would still not be round.
John: With the small amount out of spec your case is I urge you use standard od bearings!