EXHIBIT 6

[Letterhead]




PERSONAL AND CONFIDENTIAL


May 17, 1999



Board of Directors
Wyman-Gordan Company
244 Worcester Street
North Grafton, MA 01536-8001

Gentlemen:

You have requested our opinion as to the fairness from a financial point of 
view to the holders of the outstanding shares of Common Stock, par value 
$1.00 per share (the "Shares"), of Wyman-Gordon Company (the "Company") of 
the $20.00 per Share in cash proposed to be paid by Precision Castparts 
Corporation ("Buyer") in the Tender Offer and the Merger (as defined 
below) pursuant to the Agreement and Plan of Merger, dated as of May 17, 
1999, among Buyer, WGC Acquisition Corp., a wholly-owned subsidiary of Buyer 
("Acquisition Sub"), and the Company (the "Agreement"). The Agreement 
provides for a tender offer for all of the Shares (the "Tender Offer") 
pursuant to which Acquisition Sub will pay $20.00 per Share in cash for each 
Share accepted. The Agreement further provides that following completion of 
the Tender Offer, Acquisition Sub will be merged into the Company (the 
"Merger") and each outstanding Share (other than Shares already owned by 
Acquisition Sub) will be converted into the right to receive $20.00 in cash.

Goldman, Sachs & Co., as part of its investment banking business, is 
continually engaged in the valuation of businesses and their securities in 
connection with mergers and acquisitions, negotiated underwritings, 
competitive biddings, secondary distributions of listed and unlisted 
securities, private placements and valuations for estate, corporate and other 
purposes. We are familiar with the Company having acted as its financial 
advisor in connection with, and having participated in certain of the 
negotiations leading to, the Agreement. We also have provided certain 
investment banking services to Buyer from time to time, including having 
acted as managing underwriter of a public offering of $150,000,000 aggregate 
principal amount of 6 1/8% Senior Notes of Buyer due December 15, 2007 in 
December 1997, and may provide investment banking services to Buyer and its 
subsidiaries in the future. Goldman, Sachs & Co. provides a full range of 
financial advisory and securities services and, in the course of its normal 
trading activities, may from time to time effect transactions and hold 
securities, including derivative securities, of the Company or Buyer for its 
own account and for the accounts of customers.





Wyman-Gordon Company
May 17, 1999
Page Two



In connection with this opinion, we have reviewed, among other things, the 
Agreement; Annual Reports to Stockholders and Annual Reports on Form 10-K of 
the Company for the five fiscal years ended May 31, 1998; certain interim 
reports to stockholders and Quarterly Reports on Form 10-Q of the Company; 
certain other communications from the Company to its stockholders; and 
certain internal financial analyses and forecasts for the Company prepared by 
its management. We also have held discussions with members of the senior 
management of the Company regarding its past and current business operations, 
financial condition and future prospects. In addition, we have reviewed the 
reported price and trading activity for the Shares, compared certain 
financial and stock market information for the Company with similar 
information for certain other companies the securities of which are publicly 
traded, reviewed the financial terms of certain recent business combinations 
in the aerospace components industry specifically and in other industries 
generally and performed such other studies and analyses as we considered 
appropriate.

We have relied upon the accuracy and completeness of all of the financial and 
other information reviewed by us and have assumed such accuracy and 
completeness for purposes of rendering this opinion. In addition, we have not 
made an independent evaluation or appraisal of the assets and liabilities of 
the Company or any of its subsidiaries and we have not been furnished with 
any such evaluation or appraisal. Our advisory services and the opinion 
expressed herein are provided for the information and assistance of the Board 
of Directors of the Company in connection with its consideration of the 
transaction contemplated by the Agreement and such opinion does not 
constitute a recommendation as to whether or not any holder of Shares should 
tender such Shares in connection with such transaction.

Based upon and subject to the foregoing and based upon such other matters 
as we consider relevant, it is our opinion that as of the date hereof the 
$20.00 per Share in cash to be received by the holders of Shares in the 
Tender Offer and the Merger is fair from a financial point of view to such 
holders.

Very truly yours,


/s/ Goldman, Sachs & Co.
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(GOLDMAN, SACHS & CO.)