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[LOGO] BANK OF AMERICA                                   AMENDMENT TO DOCUMENTS
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                              AMENDMENT NO. TWO TO
                             BUSINESS LOAN AGREEMENT

    This Amendment No. Two (the "Amendment") dated as of March 18th, 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

     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  Subparagraph (a) of Paragraph 1.3 of the Agreement is amended in 
             its entirety to read as follows:

             "(a) Unless the Borrower elects an optional interest rate as 
                  described below, the interest rate is the Bank's Reference 
                  rate MINUS one-quarter (0.25) of one percentage point."

        2.2  Paragraph 1.5 of the Agreement is amended in its entirety to 
             read as follows:

             "1.5 OPTIONAL INTEREST RATES. Instead of the interest rate based 
             on the Bank's Reference Rate, the Borrower may elect the 
             optional interest rates listed below for this Facility No. 1 
             during interest periods agreed to by the Bank and the Borrower. 
             The optional interest rates shall be subject to the terms and 
             conditions described later in this Agreement. Any principal 
             amount bearing interest at an optional rate under this Agreement 
             is referred to as a `Portion.' The following optional interest 
             rates are available:

                    (a) the Cayman Rate plus 1.50 percentage points.
 
                    (b) the LIBOR Rate plus 1.50 percentage points."

        2.3  Subparagraph (b) of Paragraph 4.4 is amended in its entirety to 
             read as follows:

             "(b)   The Borrower will repay principal in installments on the 
             dates and in the amounts set forth on Exhibit A attached here to."

        2.4  Paragraph 4.5 of the Agreement is amended in its entirety to 
             read as follows:

             "4.5 OPTIONAL INTEREST RATES. Instead of the interest rate based 
             on the Bank's Reference Rate, the Borrower may elect the 
             optional interest rates listed below for this Facility No. 4 
             during interest periods agreed to by the Bank and the Borrower. 
             The optional interest rates shall be subject to the terms and 
             conditions described later in this Agreement. Any principal 
             amount bearing interest at an optional rate under this Agreement 
             is referred to as a `Portion.' The following optional interest 
             rates are available:

                    (a) the Cayman Rate plus 1.75 percentage points.
 
                    (b) the LIBOR Rate plus 1.75 percentage points."



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        2.5  An Exhibit A is added to the Agreement as set forth on Exhibit A 
             attached here to.

     3. 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.

        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 Teymourtache                   x /s/ Thomas M. Costales
---------------------------------          --------------------------
By: KARIM TEYMOURTACHE, VICE PRESIDENT     By: THOMAS M. COSTALES
                                           Title: CFO



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                                   EXHIBIT A

<TABLE>
<CAPTION>
                       DUE DATE                PAYMENT AMOUNT
                       --------                --------------
                       <S>                     <C>
                        March 5, 1998              $165,000
                        June 5, 1998               $165,000
                        September 8, 1998          $165,000
                        December 7, 1998           $165,000
                        March 5, 1999              $165,000
                        June 7, 1999               $165,000
                        September 7, 1999          $165,000
                        December 6, 1999           $165,000
                        March 6, 2000              $165,000
                        June 5, 2000               $165,000
                        September 5, 2000          $165,000
                        December 5, 2000           $165,000
                        March 5, 2001              $165,000
                        June 5, 2001               $165,000
                        September 5, 2001          $165,000
                        December 5, 2001           $165,000
                        March 5, 2002              $165,000
                        June 5, 2002               $165,000
                        September 5, 2002          $165,000
                        December 5, 2002           $165,000

</TABLE>


BANK OF AMERICA 
NATIONAL TRUST AND SAVINGS ASSOCIATION     IMPCO TECHNOLOGIES, INC.

x /s/ Karim Teymourtache                   x /s/ Thomas M. Costales
---------------------------------          --------------------------
By: KARIM TEYMOURTACHE, VICE PRESIDENT     By: THOMAS M. COSTALES
                                           Title: CFO