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BANK OF AMERICA                                         AMENDMENT TO DOCUMENTS
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                           AMENDMENT NO. THREE TO
                           BUSINESS LOAN AGREEMENT

      This Amendment No. Three (the "Amendment") dated as of April 9, 1998, 
is between Bank of America National Trust and Savings Association (the "Bank") 
and IMPCO Technologies, Inc. (the "Borrower").

                                 RECITALS
                                 --------

     A.  The Bank and the Borrower entered into a certain Business Loan 
Agreement dated as of October 7, 1997, as previously amended (the 
"Agreement").

     B.  The Bank and the Borrower desire to further amend the Agreement.

                                 AGREEMENT
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     1.  DEFINITIONS.  Capitalized terms used but not defined in this 
Amendment shall have the meaning given to them in the Agreement.

     2.  AMENDMENTS.  The Agreement is hereby amended as follows:

         2.1  Paragraph 4.2 of the Agreement is amended to read in its 
              entirety as follows

              "4.2  AVAILABILITY PERIOD. The loan is available in two 
              disbursements from the Bank between the date of this Agreement 
              and August 31, 1998, unless the Borrower is in default. The 
              first disbursement must be for at lease Three Million Three 
              Hundred Thousand Dollars ($3,300,000) (the 'First 
              Disbursement'). The second disbursement must be for at least 
              Six Hundred Ninety-Two Five Hundred Twenty and 78/100 Dollars 
              ($892,620.78) (the `Second Disbursement')."

         2.2  Paragraph 4.4(b) of the Agreement is amended to 
              read in its entirety as follows:

              "(b) The Borrower will repay principal as follows:

                   (i)   The Borrower will repay principal of the First 
                         Disbursement in 20 successive quarterly installments 
                         of One Hundred Sixty-Five Thousand Dollars ($165,000) 
                         starting March 5, 1998. On December 5, 2002, the 
                         Borrower will repay the remaining principal balance 
                         plus any interest then due under the First 
                         Disbursement.

                   (ii)  The Borrower will repay principal of the Second 
                         Disbursement in 20 successive quarterly installments 
                         of Thirty-Four Thousand Six Hundred Twenty-Six Dollars
                         ($34,626) starting July 31, 1998. On April 30, 2003, 
                         the Borrower will repay the remaining principal 
                         balance plus any interest then due under the Second 
                         Disbursement."

     3.  REPRESENTATIONS AND WARRANTIES.  When the Borrower signs this 
Amendment, the Borrower represents and warrants to the Bank that (a) there is 
no event which is, or with notice or lapse of time or both would be a default 
under the Agreement, (b) the representations and warranties in the Agreement 
are true as of the date of this Amendment as if made on the date of this 
Amendment, (c) this Amendment is within the Borrower's powers, has been duly 
authorized, and does not conflict with any of the Borrower's organizational 
papers, and (d) this Amendment does not conflict with any law, agreement, or 
obligation by which the Borrower is bound.

     4.  EFFECT OF AMENDMENT.  Except as provided in this Amendment, all of 
the terms and conditions of the Agreement shall remain in full force and 
effect.

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     This Amendment is executed as of the date stated at the beginning of 
this Amendment.

BANK OF AMERICA
National Trust and Savings Association     IMPCO Technologies, Inc.


X    /s/ Karim Teymouftache                X   /s/ Thomas M. Costales
     ----------------------------------        --------------------------------
By:  Karim Teymouftache, Vice President    By: Thomas M. Costales, Chief  
                                                  Financial Officer



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