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                                                                     EXHIBIT 8.1
 
                                                                   July 25, 1997
 
Neenah Foundry Company
2121 Brooks Avenue -- Box 729
Neenah, Wisconsin 54927
 
Re:  Offer for all outstanding 11 1/8% Series A Senior Subordinated Notes due
     2007 in exchange for 11 1/8% Series B Senior Subordinated Notes due 2007 of
     Neenah Foundry Company
 
Ladies and Gentlemen:
 
     We have acted as counsel to Neenah Foundry Company (the "Company") in
connection with the proposed offer (the "Exchange Offer") to exchange an
aggregate principal amount of up to $150,000,000 of its 11 1/8% Series B Senior
Subordinated Notes due 2007 (the "New Notes") for a like principal amount of its
11 1/8% Series A Senior Subordinated Notes due 2007 (the "Old Notes").
 
     On the basis of the foregoing, it is our opinion that the statements
regarding the Exchange Offer described in the section titled "Certain Federal
Income Tax Considerations" in the Company's Amendment No. 1 Registration
Statement on Form S-4 (File No. 333-28751), filed with the Securities and
Exchange Commission on July 25, 1997 (the "Registration Statement"), are correct
in all material respects.
 
     We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to this firm in the Registration
Statement.
 
                                          Very truly yours,
 
                                          /s/ KIRKLAND & ELLIS
 
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                                          Kirkland & Ellis