Exhibit 10.18 IMPCO Detroit Headquarters Letterhead 35715 Sterling Drive Sterling Heights, MI 48312 Tel: (810) 819-0800 Fax: (810) 979-8910 www.impcotechnologies.com AMENDMENT TO THE LEASE BETWEEN KLEIN INVESTMENTS AND IMPCO TECHNOLOGIES, INC. Pursuant to Section 12.1 of the lease between Klein Investments and IMPCO Technologies, IMPCO Technologies Inc. assigns this lease to Quantum Technologies, Inc., a wholly-owned subsidiary of IMPCO Technologies, as of October 31, 2000 with the consent of Klein Investments. In return for acceptance of this assignment IMPCO Technologies, Inc. will guaranty performance of all terms and conditions under this lease by Quantum Technologies, Inc. to Klein Investments. IN WITNESS WHEREOF, the parties hereto have executed this Amendment by their officers thereunto duly authorized as of the day and year first written above. IMPCO Technologies, Inc. Klein Investments By: /s/ Don Dominic BY: /s/ William A. Klein --------------------------- -------------------- Don Dominic, 2-8-2001 TITLE: VP & Secretary TITLE: General Partner ----------------- Quantum Technologies, Inc. BY: /s/ Syed Hussain ---------------------- TITLE: President -------------------