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                                                                    EXHIBIT 10.4

                       EMPLOYEE BENEFIT MATTERS AGREEMENT

     This EMPLOYEE BENEFIT MATTERS AGREEMENT (this "Agreement") is dated as of
July 23, 2002, by and between IMPCO Technologies, Inc., a Delaware corporation
("IMPCO") and Quantum Fuel Systems Technologies Worldwide, Inc., a Delaware
corporation ("Quantum").

     WHEREAS, in accordance with that certain Contribution and Distribution
Agreement, dated as of July 23, 2002, between IMPCO and Quantum (the
"Distribution Agreement"), IMPCO is contributing to Quantum certain assets
relating to its Automotive OEM Business as part of a restructuring of IMPCO to
separate from IMPCO all of the Automotive OEM Business;

     WHEREAS, in order to further effect the foregoing separation, the Board of
Directors of IMPCO has determined that it is appropriate, desirable and in the
best interests of IMPCO and its businesses as well as of the holders of shares
of common stock, par value $0.001 per share, of IMPCO (the "IMPCO Common
Stock"), for IMPCO to distribute to the holders of the IMPCO Common Stock all
the outstanding shares of common stock, par value $0.001 per share, of Quantum
(the "Quantum Common Stock") as set forth in the Distribution Agreement; and

     WHEREAS, IMPCO and Quantum have determined that it is necessary and
desirable to allocate and assign responsibility for certain employee benefit
matters in respect of such entities on and after the Effective Time (as defined
herein).

     NOW, THEREFORE, in consideration of the mutual promises and covenants
contained herein, IMPCO and Quantum agree as follows:


                                    ARTICLE I
                                   DEFINITIONS

     SECTION 1.1 DEFINITIONS. Capitalized terms used in this Agreement and not
defined herein shall have the meanings that such terms have in the Distribution
Agreement. As used in this Agreement, the following terms shall have the
following meanings:

     "Action" shall mean any action, suit, arbitration, inquiry, proceeding or
investigation by or before any court, any governmental or other regulatory or
administrative agency, body or commission or any arbitration tribunal.

     "Affiliate" shall mean, when used with respect to a Person, another Person
that controls, is controlled by, or is under common control (within the meaning
of Section 414(b), (c), (m) or (o) of the Code) with the Person specified.

     "Ancillary Agreements" shall mean all of the written agreements,
instruments, assignments or other written arrangements (other than this
Agreement and the Distribution Agreement) entered into in connection with the
transactions contemplated by this Agreement and the Distribution Agreement.

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     "Assets" shall have the meaning set forth in Section 1.1(j) of the
Distribution Agreement.

     "Board of Directors" shall mean, when used with respect to a specified
corporation, the board of directors of the corporation so specified.

     "Business Entity" shall mean any corporation, partnership, limited
liability company or other entity which may legally hold title to Assets.

     "COBRA" shall mean the Consolidated Omnibus Budget Reconciliation Act of
1985, as amended, and the regulations promulgated thereunder, including any
successor legislation.

     "Code" shall mean the Internal Revenue Code of 1986, as amended, and the
regulations promulgated thereunder, including any successor legislation.

     "Distribution" shall mean the distribution on the Distribution Date to
holders of record of shares of IMPCO Common Stock as of the Distribution Record
Date of the Quantum Common Stock owned by IMPCO on the basis of one share of
Quantum Common Stock for every outstanding share of IMPCO Common Stock.

     "Distribution Agreement" shall have the meaning set forth in the recitals
hereto.

     "Distribution Date" shall mean July 23, 2002.

     "Distribution Record Date" shall mean July 5, 2002.

     "Effective Time" shall mean 11:59 p.m. Eastern Time, on the Distribution
Date.

     "Employee Benefit Litigation Liability" shall mean, with respect to a
Business Entity a liability relating to a controversy, dispute or claim arising
out of, in connection with or in relation to the interpretation, performance,
nonperformance, validity or breach of an Employee Benefit Plan of such Business
Entity or otherwise arising out of, or in any way related to such Employee
Benefit Plan, including, without limitation, any claim based on contract, tort,
statute or constitution.

     "Employee Benefit Plans" shall mean, with respect to a Business Entity, all
"employee benefit plans" (within the meaning of Section 3(3) of ERISA),
"multiemployer plans" (within the meaning of Section 3(37) of ERISA),
retirement, pension, savings, profit-sharing, welfare, stock purchase, stock
option, equity-based, severance, employment, change-in-control, fringe benefit,
collective bargaining, bonus, incentive, deferred compensation, worker's
compensation and all other employee benefit plans, agreements, programs,
policies or other arrangements (including any funding mechanisms therefor),
whether or not subject to ERISA, whether formal or informal, oral or written,
legally binding or not, under which (i) any past, present or future employee of
the Business Entity or its Subsidiaries has a right to benefits and (ii) the
Business Entity or its Subsidiaries has (or could have) any liabilities.

     "Employee Benefit Records" shall mean all agreements, documents, books,
records or files relating to the Employee Benefit Plans of IMPCO and Quantum.

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     "Employee Transfer Date" shall mean July 23, 2002.

     "Employee Welfare Benefit Plans" shall mean, with respect to a Business
Entity, all Employee Benefit Plans that are "welfare plans" within the meaning
of Section 3(1) of ERISA.

     "Employer Stock" shall mean, after the Distribution Date, Quantum Common
Stock credited to the Non-Employer Stock Accounts of a Quantum Employee and
IMPCO Common Stock credited to the Non-Employer Stock Account of an IMPCO
Retained Employee in the respective savings plan in which such employee
participates, pursuant to Section 2.4.

     "ERISA" shall mean the Employee Retirement Income Security Act of 1974, as
amended, and the regulations promulgated thereunder, including any successor
legislation.

     "Former Quantum Employee" shall mean any person employed at any time by the
IMPCO Group or the Quantum Group primarily in connection with the Quantum
Business and who is, at the Employee Transfer Date, no longer employed by the
IMPCO Group or the Quantum Group.

     "IMPCO" shall have the meaning set forth in the recitals hereto.

     "IMPCO Common Stock" shall have the meaning set forth in the recitals
hereto.

     "IMPCO Deferred Compensation Plan" shall mean the IMPCO Technologies, Inc.
Deferred Compensation Plan, as in effect from time to time.

     "IMPCO Employees" shall mean persons who, at any time prior to the Employee
Transfer Date, were employed by the IMPCO Group.

     "IMPCO Flexible Benefits Plan" shall mean the IMPCO Technologies, Inc.
Premium Only Plan, a "cafeteria plan" within the meaning of Section 125 of the
Code.

     "IMPCO Group" shall mean IMPCO (other than any member of the Quantum Group)
and each person that is a Subsidiary of IMPCO immediately prior to the Employee
Transfer Date.

     "IMPCO Nonqualified Plans" shall have the meaning set forth in Section 3.1
of this Agreement.

     "IMPCO Retained Employees" shall mean persons who, immediately after the
Employee Transfer Date, are employed by the IMPCO Group (including persons who
would otherwise be deemed to be IMPCO Retained Employees who are absent from
work by reason of disability or leave of absence and inactive employees treated
as such by agreement therewith) but shall not include any persons who are or
become Quantum Employees on or after such date.

     "IMPCO Savings Plan" shall mean the IMPCO Technologies, Inc. Investment and
Tax Savings Plan, as in effect from time to time.

     "IMPCO Stock Option" shall mean any option to purchase IMPCO Common Stock.

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     "IMPCO Stock Option Plans" shall mean the 1989 Incentive Stock Option Plan,
the 1991 Executive Stock Option Plan, the 1993 Stock Option Plan for
Non-Employee Directors, the 1996 Incentive Stock Option Plan, the 1997 Incentive
Stock Option Plan, the 2000 Incentive Stock Option Plan, each as in effect at
the Effective Time, and any other stock option plan established by IMPCO or any
predecessor before the Distribution Date.

     "IMPCO Supplemental Retirement Plan" shall mean the IMPCO Technologies Inc.
Supplemental Retirement Plan, as in effect from time to time.

     "Information Statement" shall mean the Information Statement sent to the
holders of shares of IMPCO Common Stock in connection with the Distribution,
including any amendment or supplement thereto.

     "Non-Employer Stock Fund" shall have the meaning set forth in Section 2.4
of this Agreement.

     "Person" shall mean any natural person, Business Entity, corporation,
business trust, joint venture, association, company, partnership, limited
liability company, other entity or government, or any agency or political
subdivision thereof.

     "Plan Transfer Date" shall have the meaning set forth in Section 2.2(b) of
this Agreement.

     "Quantum" shall have the meaning set forth in the recitals hereto.

     "Quantum 2002 Stock Incentive Plan" shall mean the Quantum Fuel Systems
Technologies Worldwide, Inc. 2002 Stock Incentive Plan.

     "Quantum Common Stock" shall have the meaning set forth in the recitals
hereto.

     "Quantum Employees" shall mean the IMPCO Employees who, immediately after
the Employee Transfer Date, are employed by the Quantum Group (including persons
who would otherwise be deemed to be Quantum Employees who are absent from work
by reason of disability or leave of absence and inactive employees treated as
such by agreement therewith) but shall not include any persons who are or become
Quantum Employees after such date.

     "Quantum Group" shall mean Quantum and each Business Entity which is
contemplated to remain or become a Subsidiary of Quantum pursuant to the
Distribution Agreement.

     "Quantum Savings Plan" shall have the meaning set forth in Section 2.2(a)
of this Agreement.

     "Securities Act" shall mean the Securities Act of 1933, as amended.

     "Service" shall mean the U.S. Internal Revenue Service or any successor
entity thereto.

     "Subsidiary" shall mean any corporation, partnership or other entity of
which another entity (i) owns, directly or indirectly, ownership interests
sufficient to elect a majority of the

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Board of Directors (or persons performing similar functions) (irrespective of
whether at the time any other class or classes of ownership interests of such
corporation, partnership or other entity shall or might have such voting power
upon the occurrence of any contingency) or (ii) is a general partner or an
entity performing similar functions (e.g., a trustee).


                                   ARTICLE II
                              COMPANY SAVINGS PLANS

     SECTION 2.1 IMPCO SAVINGS PLAN. From and after the Employee Transfer Date,
IMPCO shall continue to sponsor the IMPCO Savings Plan for the benefit of IMPCO
Retained Employees who, prior to such date, were participants thereunder. Active
participation of all Quantum Employees in the IMPCO Savings Plan shall cease
immediately prior to the Employee Transfer Date, and the trustee of such plan
shall not accept further contributions made by or on behalf of the Quantum
Employees, other than contributions that accrued prior to the Employee Transfer
Date. Except as may be required by Section 411(d)(3) of the Code or other
applicable law, nothing contained in this Article II shall have the effect of
accelerating the degree to which any individual has a vested interest in the
IMPCO Savings Plan or the Quantum Savings Plan.

     SECTION 2.2 QUANTUM SAVINGS PLAN.

     (a) As of the Employee Transfer Date, Quantum shall adopt a defined
contribution plan that is intended to qualify under Sections 401(a) and 40l(k)
of the Code (the "Quantum Savings Plan"), under which benefits shall generally
be provided for Quantum Employees. Subject to such adoption, Quantum agrees to
use its reasonable best efforts to cause the applicable fiduciaries of the
Quantum Savings Plan to accept a transfer of assets and liabilities from the
IMPCO Savings Plan, in accordance with the spin-off provisions set forth under
Section 414(l) of the Code and other applicable law, representing the full
account balances of Quantum Employees for all periods of participation in the
IMPCO Savings Plan through the Employee Transfer Date (including all
contributions and all earnings attributable thereto).

     (b) Prior to the date on which the transfer of assets and liabilities to
the Quantum Savings Plan may occur (the "Plan Transfer Date"), which date shall
occur as promptly as practicable following the Employee Transfer Date and be
subject to the fiduciaries of the Quantum Savings Plan accepting a transfer of
assets and liabilities under Section 2.2(a), IMPCO shall (i) cause the trustee
of the IMPCO Savings Plan to segregate, in accordance with the spin-off
provisions set forth under Section 414(l) of the Code and other applicable law,
the assets of the IMPCO Savings Plan representing the full account balances of
Quantum Employees for all periods of participation in the IMPCO Savings Plan
through the Employee Transfer Date (including all contributions and all earnings
attributable thereto); (ii) make all required filings and submissions to the
appropriate governmental agencies; and (iii) make all required amendments to the
IMPCO Savings Plan and related trust agreement necessary to provide for the
segregation of assets described in this Section 2.2(b).

     (c) On the Plan Transfer Date, IMPCO shall cause the trustee of the IMPCO
Savings Plan to transfer to the trustee of the Quantum Savings Plan the account
balances (inclusive of

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loans) of any participating Quantum Employees, as determined under Section
2.2(b). Such transfer shall be "in kind," based on those investment funds in
which such account balances are then invested (including, but not limited to,
the employer stock funds described in Section 2.4) or in such other form as
IMPCO and Quantum may mutually agree; provided, however, that any plan loans to
Quantum Employees shall be transferred in the form of notes. In consideration of
the segregation and transfer of assets described herein, the Quantum Savings
Plan shall, as of the Plan Transfer Date, assume all liabilities attributable to
such assets. Upon the full completion of the transfer described herein, IMPCO
and the IMPCO Savings Plan shall be relieved of, and Quantum and the Quantum
Savings Plan shall assume, all liabilities for the payment of any account
balances transferred from the IMPCO Savings Plan to the Quantum Savings Plan.

     SECTION 2.3 OUTSTANDING LOANS. Subject to the fiduciaries of the Quantum
Savings Plan accepting a transfer of assets and liabilities under Section
2.2(a), with respect to any Quantum Employees who have outstanding plan loans
originally made from the IMPCO Savings Plan, such Employees shall be permitted
to repay such loans to the IMPCO Savings Plan by way of regular deductions from
their paychecks, and, prior to the Plan Transfer Date, IMPCO or Quantum (as the
case may be) shall cause all such deductions to be forwarded to the IMPCO
Savings Plan as promptly as practicable. From and after the Plan Transfer Date,
all plan loan repayments made by Quantum Employees shall be remitted exclusively
to the Quantum Savings Plan but only to the extent such plan loans are
transferred to the Quantum Savings Plan. Unless expressly contemplated by this
Agreement, in no event will the transactions contemplated by this Agreement
alter the terms of the applicable notes or the loan provisions of the Quantum
Savings Plan or the IMPCO Savings Plan.

     SECTION 2.4 EMPLOYER STOCK FUND. Effective as of the Employee Transfer
Date, an IMPCO Common Stock fund shall be added as an investment option to the
Quantum Savings Plan, and the IMPCO Savings Plan shall provide for both an IMPCO
Common Stock fund and a Quantum Common Stock fund as investment options. The
Quantum Common Stock fund in the IMPCO Savings Plan and the IMPCO Common Stock
fund in the Quantum Savings Plan are each referred to as a "Non-Employer Stock
Fund" with respect to the applicable Plan. Unless IMPCO and Quantum agree
otherwise, each Non-Employer Stock Fund shall be maintained under the respective
Plan through December 31, 2002. After such date, IMPCO and Quantum agree to
cooperate with each other with respect to the disposition of the stock when
either party decides to liquidate or otherwise terminate the Non-Employer Stock
Fund in its Savings Plan. In the absence of any agreement regarding such
liquidation, the liquidation of each Non-Employer Stock Fund shall be made in a
ratable manner over a period of twelve months. The IMPCO Savings Plan and the
Quantum Savings Plan shall each provide that, after the Distribution Date, no
new contributions may be invested in, and no amounts may be transferred from
other investment options to the Non-Employer Stock Fund under the respective
Plan (except for the distribution of Quantum Common Stock in respect of
outstanding shares of IMPCO Common Stock effected by the Distribution). To the
extent the parties determine it is necessary to preserve the tax status of the
Distribution under the Code, the IMPCO Savings Plan shall provide that no
earnings or dividends under its Non-Employer Stock Fund may be reinvested in
Quantum Common Stock and the Quantum Savings Plan shall provide that no earnings
or dividends under its Non-Employer Stock Fund may be reinvested in IMPCO Common
Stock; provided, however, this requirement shall not prohibit such earnings and

                                       6

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dividends from remaining in the applicable Non-Employer Stock Fund as cash or as
an amount that is invested in any non-stock investment in such fund.

     SECTION 2.5 ALLOCATION OF LIABILITIES. From and after the Employee Transfer
Date, the Quantum Savings Plan shall assume all liabilities relating to the
payment of benefits to Quantum Employees in the IMPCO Savings Plan. The IMPCO
Group shall retain all other liabilities relating to the IMPCO Savings Plan.


                                   ARTICLE III
                                 EXECUTIVE PLANS

     SECTION 3.1 IMPCO NONQUALIFIED PLANS. From and after the Effective Time,
IMPCO shall continue to sponsor the IMPCO Supplemental Retirement Plan and the
IMPCO Deferred Compensation Plan (collectively, the "IMPCO Nonqualified Plans")
for the benefit of participants thereunder. Active participation of all Quantum
Employees in the IMPCO Nonqualified Plans shall cease immediately prior to the
Employee Transfer Date, and the trustee(s) of such plans shall not accept
further contributions made by or on behalf of the Quantum Employees, other than
contributions that accrued prior to the Employee Transfer Date. The IMPCO
Nonqualified Plans shall make distributions to Quantum Employees in such manner
and at such times as required under the terms of the IMPCO Nonqualified Plans
and any applicable payment elections by participants; provided, however, at
IMPCO and Quantum's mutual election on or after the Employee Transfer Date, the
aggregate deferred account balances of those Quantum Employees in the IMPCO
Nonqualified Plans may be transferred from the IMPCO rabbi trust to the Quantum
rabbi trust. Upon the completion of such transfer of assets, Quantum shall
assume the liabilities for the payment of benefits associated with the
transferred assets with respect to the affected Quantum Employees.

     SECTION 3.2 QUANTUM NONQUALIFIED PLANS. As of the Employee Transfer Date,
Quantum shall adopt a nonqualified deferred compensation plan for the benefit of
a select group of management or highly compensated Quantum Employees. In
conjunction with adopting such plan, Quantum shall adopt a rabbi trust agreement
with terms that are substantially similar to the terms of the IMPCO rabbi trust
agreement.


                                   ARTICLE IV
                                  WELFARE PLANS

     SECTION 4.1 EMPLOYEE WELFARE BENEFIT PLANS. From and after the Effective
Time, IMPCO shall sponsor its Employee Welfare Benefit Plans for the benefit of
IMPCO Retained Employees who, prior to the Effective Time, were receiving
benefits under such plans. Active participation of all Quantum Employees in the
IMPCO Employee Welfare Benefit Plans shall cease as of 11:59 p.m. Eastern Time
on July 31, 2002. From and after such time, Quantum shall sponsor its Employee
Welfare Benefit Plans for the benefit of Quantum Employees. Notwithstanding the
foregoing, neither IMPCO nor Quantum shall have any obligation to sponsor any
specific Employee Welfare Benefit Plan from or after the Employee Transfer Date.

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     SECTION 4.2 DOLLAR LIMITS. With respect to any medical and dental plan that
may be sponsored by Quantum from and after August 1, 2002, Quantum shall give
effect (subject to approval by applicable insurers), in determining any
deductible, maximum out-of-pocket limitations and annual plan maximums, to
claims incurred during 2002 prior to August 1, 2002 by Quantum Employees under
similar plans maintained by IMPCO (or any Affiliate thereof) for their benefit
immediately prior to August 1, 2002.

     SECTION 4.3 FLEXIBLE SPENDING ACCOUNTS. As of the Employee Transfer Date,
Quantum shall adopt a Code Section 125 plan for the benefit of the Quantum
Employees, the material terms of which plan shall be substantially similar to
those of the IMPCO Code Section 125 plan. Active participation of all Quantum
Employees in the IMPCO Code Section 125 plan shall cease immediately prior to
the Employee Transfer Date, and such plan shall not accept further contributions
made by or on behalf of the Quantum Employees, other than contributions that
accrued prior to the Employee Transfer Date. With respect to amounts deferred
into the IMPCO Code Section 125 plan by Quantum Employees prior to the Employee
Transfer Date, such amounts shall remain available for reimbursement of
qualified medical and dependent care expenses incurred prior to the Employee
Transfer Date for a period of time to be mutually agreed upon by IMPCO and
Quantum (the "Run-out Period"). Any claims relating to expenses incurred prior
to the Employee Transfer Date that are not submitted to IMPCO prior to the end
of the Run-out Period shall not be eligible for reimbursement. Any amounts
deferred by Quantum Employees under the IMPCO Plan that are not paid out in
connection with claims submitted prior to the end of the Run-out Period shall be
forfeited. Reimbursement for medical and dependent care expenses incurred after
the Employee Transfer Date shall be subject to the terms of the Quantum Code
Section 125 Plan.

     SECTION 4.4 ALLOCATION OF LIABILITIES.

     (a) Except to the extent welfare benefits are funded by employee
contributions, the IMPCO Group shall retain responsibility for and continue to
pay all premiums, expenses and benefits relating to the IMPCO Employee Welfare
Benefit Plans with respect to claims incurred (for self-insured plans) or
premiums due (for insured plans) (i) prior to August 1, 2002 by IMPCO Employees
(including Quantum Employees participating in such IMPCO Welfare Benefit Plans
prior to August 1, 2002) as well as their covered dependents and (ii) from and
after August 1, 2002, by IMPCO Retained Employees as well as their covered
dependents.

     (b) Except to the extent welfare benefits are funded by employee
contributions, the Quantum Group shall assume responsibility for and pay all
premiums, expenses and benefits relating to the Quantum Group Employee Welfare
Benefit Plans with respect to claims incurred (for self-insured plans) or
premiums due (for insured plans) from and after August 1, 2002 by Quantum
Employees as well as their covered dependents.

     (c) For the purposes of this Section 4.4, a claim is deemed incurred when
the services that are the subject of the claim are performed; in the case of
life insurance, when the death occurs; in the case of long-term disability, when
the disability occurs; and, in the case of a hospital stay, when the employee
first enters the hospital. Notwithstanding the foregoing, claims incurred by any
employee of a pre-Distribution Subsidiary of IMPCO or their covered dependents
under any Employee Welfare Benefit Plan maintained by such Subsidiary solely for

                                       8

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the benefit of its employees and their dependents shall, whether incurred prior
to, on or after August 1, 2002, be the sole responsibility and liability of that
Subsidiary.

     (d) The IMPCO Group shall be responsible for making COBRA coverage
available with respect to any IMPCO Employees and Quantum Employees (and their
covered dependents) who experience a "qualifying event" on or before August 1,
2002, including without limitation any such event arising from the transactions
contemplated in this Agreement. The Quantum Group shall be responsible for
making COBRA coverage available with respect to the Quantum Employees (and their
covered dependents) under any applicable Quantum Employee Benefit Plans
subsequent to August 1, 2002. Notwithstanding the foregoing, a pre-Distribution
Subsidiary of IMPCO shall be responsible for all COBRA coverage for its former
employees and covered dependents who participated in a plan maintained solely
for their benefit whether the applicable event occurs prior to, on or after
August 1, 2002.


                                    ARTICLE V
                               EQUITY-BASED PLANS

     SECTION 5.1 IMPCO STOCK OPTIONS. IMPCO Stock Options shall be treated as
follows:

     (a) As of the Distribution Date, each IMPCO Stock Option outstanding as of
the Distribution Record Date and not exercised prior to the Distribution Date
(each an "IMPCO Option") shall be adjusted as set forth in this Section 5.1.
Each IMPCO Option shall be converted (an "Adjusted Option"), as of the
Distribution Date, into two options: an option (the "IMPCO Adjusted Option") to
purchase the same number of shares of IMPCO Common Stock covered by the IMPCO
Option and as to which the IMPCO Option has not been exercised as of the
Distribution Date ("IMPCO Option Number") and an option (the "Quantum Option")
to purchase a number of shares of Quantum Common Stock equal to the IMPCO Option
Number times a fraction, the numerator of which is the total number of shares of
Quantum Common Stock distributed to IMPCO stockholders in the Distribution and
the denominator of which is the total number of shares of IMPCO Common Stock
outstanding on Distribution Record Date (the "Distribution Ratio"). The terms of
the IMPCO Adjusted Option and the Quantum Option (other than the exercise price
and the number of shares) shall be substantially the same as the IMPCO Option.

     (b) The exercise prices per share for each IMPCO Adjusted Option and the
Quantum Option shall be established, as set forth in Schedule 5.1(b) hereto, in
a manner so that: (a) the aggregate "intrinsic value" (i.e. the market value of
the stock underlying the option, less the exercise price of such option,
multiplied by the number of shares then covered by such option) after the
Distribution of the IMPCO Adjusted Option plus the Quantum Option is not greater
than the intrinsic value of the related IMPCO Option immediately prior to the
Distribution, and (b) the ratio of the exercise price per option to the market
value per share after the Distribution is not lower than the ratio of the
exercise price of the IMPCO Option to the market value per share of IMPCO Common
Stock immediately prior to the Distribution. The determination of the exercise
prices for each IMPCO Adjusted Option and Quantum Option shall be made by IMPCO
as advised by its professional advisors.

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     (c) The Quantum Options to be granted with respect to each Adjusted Option
shall be issued under the Quantum 2002 Stock Incentive Plan, and Quantum shall
take all corporate action and make all required filings under applicable state
blue sky laws and the Securities Act to (i) issue the Quantum Options required
under this Section 5.1 and (ii) to register or qualify the Quantum Options
and/or the underlying shares of Quantum Common Stock so that the shares of
Quantum Common Stock acquired upon exercise of each Quantum Option are freely
tradable under the Securities Act (except for shares acquired by Affiliates of
Quantum) and each applicable state's blue sky laws.

     (d) Exceptions. The Board of Directors of IMPCO may determine that certain
IMPCO Stock Options described above may not be adjusted as described above, but
instead shall be subject to such conditions as the Board of Directors of IMPCO
(or the compensation committee thereof) shall determine to the extent necessary
to avoid adverse tax consequences to option holders who are not U.S. residents.

     (e) IMPCO and Quantum acknowledge that the adjustment to IMPCO Options
under this Article V will be implemented in part by the issuance of the Quantum
Options under the terms of the Quantum 2002 Stock Incentive Plan.

     (f) After the Distribution Date, (i) IMPCO Options, regardless of by whom
held, shall be settled by IMPCO pursuant to the terms of the applicable IMPCO
Stock Option Plan, and (ii) Quantum Options, regardless of by whom held, shall
be settled by Quantum pursuant to the terms of the Quantum 2002 Stock Incentive
Plan.

     SECTION 5.2 ALLOCATION OF LIABILITIES. Except as provided in Article V of
the Tax Allocation and Indemnification Agreement, (a) the Quantum Group shall
assume all liabilities with respect to awards granted pursuant to the Quantum
2002 Stock Incentive Plan, and (b) the IMPCO Group shall retain all other
liabilities with respect to awards granted pursuant to the IMPCO Stock Option
Plans (including, but not limited to, awards granted to IMPCO Retained
Employees).


                                   ARTICLE VI
                          OTHER EMPLOYEE BENEFIT ISSUES

     SECTION 6.1 EMPLOYEE BENEFIT LITIGATION LIABILITIES.

     (a) Except as otherwise expressly provided in Section 6.1(b) below or
otherwise in this Agreement, the Quantum Group shall assume all Employee Benefit
Litigation Liabilities that are asserted by Quantum Employees and all employees
of Quantum following the Effective Time, and the IMPCO Group shall retain all
Employee Benefit Litigation Liabilities that are asserted by all other IMPCO
Employees.

     (b) With respect to any Former Quantum Employee, the IMPCO Group shall
assume and be liable for any Employee Benefit Litigation Liabilities asserted by
Former Quantum Employees arising from or in connection with the IMPCO
Nonqualified Plans, the IMPCO Savings Plan and the IMPCO Stock Option Plans, and
the Quantum Group shall assume and be

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liable for all other Employee Benefit Litigation Liabilities asserted by Former
Quantum Employees.

     SECTION 6.2 WORKERS' COMPENSATION. The IMPCO Group shall retain all
liabilities relating to, arising out of, or resulting from workers' compensation
claims that were incurred (a) prior to the Effective Time with respect to IMPCO
Employees (not including any Quantum Employees) and (b) on and after the
Effective Time with respect to IMPCO Retained Employees. The Quantum Group shall
retain all liabilities relating to workers' compensation claims that were
incurred (a) prior to the Effective Time with respect to Quantum Employees and
(b) on and after the Effective Time with respect to Quantum Employees. For
purposes of this paragraph, a claim is deemed incurred upon the occurrence of
the event giving rise to eligibility for workers' compensation benefits or upon
an occupational disease becoming manifest, as the case may be.

     SECTION 6.3 PAYROLL TAXES AND REPORTING OF COMPENSATION. IMPCO, Quantum and
their respective Affiliates agree to take such action as may be reasonably
necessary or appropriate to minimize liabilities related to the payroll tax
payments of IMPCO, Quantum and each Affiliate after the Effective Time,
including without limitation those actions which are consistent with the
treatment of Quantum as a successor employer under Treas. Reg. ss.
31.3121(a)(1)-1(b). IMPCO, Quantum and each Affiliate shall bear its own
responsibility for payroll tax obligations and for the proper reporting to the
appropriate government authorities of compensation earned by their respective
employees after the Effective Time, including, subject to Article V of the Tax
Allocation and Indemnification Agreement, compensation related to the exercise
of stock options.


                                   ARTICLE VII
                           BENEFIT PLAN PARTICIPATION

     SECTION 7.1 IMPCO PLANS. Notwithstanding any provision of this Agreement to
the contrary, unless otherwise provided herein, effective as of the Effective
Time, all Quantum Employees shall cease participation in all IMPCO Employee
Benefit Plans and the Quantum Group shall cease to be a "participating employer"
in any of the IMPCO Benefit Plans.

     SECTION 7.2 QUANTUM PLANS. (a) With respect to any newly created Employee
Benefit Plan sponsored by the Quantum Group after the Employee Transfer Date or
the Effective Time, whichever is applicable, the Quantum Group shall cause to be
recognized (to the extent applicable) each Quantum Employee's (i) past service
with the IMPCO Group to the extent recognized under similar plans maintained by
the IMPCO Group immediately prior to the relevant date and (ii) accrued but
unused vacation time and sick days, and (b) any Quantum Employee who
participated in an IMPCO Employee Benefit Plan immediately prior to the relevant
date shall be entitled to immediate participation in any substantially similar
Employee Benefit Plan sponsored by the Quantum Group.

     SECTION 7.3 SUBSEQUENT EMPLOYER. If, during the one-year period following
the Effective Time, an IMPCO Retained Employee or a Quantum Employee terminates
employment with his or her employer and then immediately commences employment

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with the Quantum Group or the IMPCO Group, respectively, the subsequent employer
shall cause to be recognized (to the extent applicable) such employee's past
service with the Quantum Group or the IMPCO Group to the extent recognized under
any substantially similar plans maintained by the prior employer.

     SECTION 7.4 RIGHT TO AMEND OR TERMINATE. Except as specifically provided
herein, nothing in this Agreement shall be construed or interpreted to restrict
the IMPCO Group's or the Quantum Group's right or authority to amend or
terminate any of their Employee Benefit Plans following the Effective Time.


                                  ARTICLE VIII
                              ACCESS TO INFORMATION

     SECTION 8.1 ACCESS TO INFORMATION. Article IV of the Distribution Agreement
shall govern the rights of the IMPCO Group and the Quantum Group with respect to
access to information. The term "Records" in that Article shall be read to
include all records related to eligibility and benefits information for and the
administration of the IMPCO and Quantum Employee Benefit Plans.


                                   ARTICLE IX
                                 INDEMNIFICATION

     SECTION 9.1 INDEMNIFICATION. Except to the extent inconsistent with Article
V of the Tax Allocation and Indemnification Agreement, Article III of the
Distribution Agreement shall govern the rights of the IMPCO Group and the
Quantum Group with respect to indemnification. The term "IMPCO Liabilities" in
that Article shall be read to include all liabilities assumed or retained by the
IMPCO Group pursuant to this Agreement. The term "Quantum Liabilities" in that
Article shall be read to include all liabilities assumed or retained by the
Quantum Group pursuant to this Agreement.


                                    ARTICLE X
                               DISPUTE RESOLUTION

     SECTION 10.1 DISPUTE RESOLUTION. Article VII of the Distribution Agreement
shall govern the rights of the IMPCO Group and the Quantum Group with respect to
dispute resolution.


                                   ARTICLE XI
                                  MISCELLANEOUS

     SECTION 11.1 COMPLETE AGREEMENT; CONSTRUCTION. This Agreement, including
the Exhibits and Schedules (if any), and the Distribution Agreement and
Ancillary Agreements shall constitute the entire agreement between the parties
with respect to the subject matter hereof and shall supersede all previous
negotiations, commitments and

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<PAGE>

writings with respect to such subject matter. In the event of any inconsistency
between this Agreement and any Schedule hereto, the Schedule shall prevail.

     SECTION 11.2 ANCILLARY AGREEMENTS. This Agreement is not intended to
address, and should not be interpreted to address, the matters specifically and
expressly covered by the Ancillary Agreements.

     SECTION 11.3 COUNTERPARTS. This Agreement may be executed in one or more
counterparts, all of which shall be considered one and the same agreement, and
shall become effective when one or more such counterparts have been signed by
each of the parties and delivered to the other parties.

     SECTION 11.4 SURVIVAL OF AGREEMENTS. Except as otherwise contemplated by
this Agreement, all covenants and agreements of the parties contained in this
Agreement shall survive the Distribution Date.

     SECTION 11.5 EXPENSES. Except as otherwise set forth in this Agreement, all
costs and expenses in connection with the preparation, execution, delivery and
required implementation of this Agreement shall be charged to and paid by the
parties in accordance with Section 9.5 of the Distribution Agreement.

     SECTION 11.6 NOTICES. All notices and other communications hereunder shall
be in writing and hand delivered or mailed by registered or certified mail
(return receipt requested) to the parties at the following addresses (or at such
other addresses for a party as shall be specified by like notice) and will be
deemed given on the date on which such notice is received, as evidenced by
written receipt, acknowledgement or other evidence of actual receipt:

     if to IMPCO, to:

          IMPCO Technologies, Inc.
          16804 Gridley Place
          Cerritos, CA 90703
          Telecopy: (562) 924-8069
          Attn: Chief Financial Officer

     with a copy to:

          Morrison & Foerster LLP
          555 West Fifth Street
          Los Angeles, CA 90013
          Telecopy: (213) 892-5641
          Attn: Johnathan F. Atzen, Esq.

                                       13

<PAGE>


     if to Quantum, to:

          Quantum Fuel Systems Technologies Worldwide, Inc.
          17872 Cartwright Road
          Irvine, CA 92614
          Telecopy: (949) 474-3086
          Attn:  President

     SECTION 11.7 WAIVERS. The failure of any party to require strict
performance by any other party of any provision in this Agreement will not waive
or diminish that party's right to demand strict performance thereafter of that
or any other provision hereof.

     SECTION 11.8 AMENDMENTS. Subject to the terms of Section 11.11 hereof, this
Agreement may not be modified or amended except by an agreement in writing
signed by each of the parties hereto.

     SECTION 11.9 ASSIGNMENT. This Agreement shall not be assignable, in whole
or in part, directly or indirectly, by operation of law or otherwise, by any
party hereto without the prior written consent of the other parties hereto, and
any attempt to assign any rights or obligations arising under this Agreement
without such consent shall be void.

     SECTION 11.10 SUCCESSORS AND ASSIGNS. The provisions to this Agreement
shall be binding upon, inure to the benefit of and be enforceable by the parties
and their respective successors and permitted assigns.

     SECTION 11.11 TERMINATION. This Agreement may be terminated and may be
amended, modified or abandoned at any time prior to the Distribution by and in
the sole discretion of IMPCO without the approval of the shareholders of IMPCO.
In the event of such termination, no party shall have any liability of any kind
to any other party or any other person. After the Distribution, this Agreement
may not be terminated except by an agreement in writing signed by the parties.

     SECTION 11.12 SUBSIDIARIES. Each of the parties hereto shall cause to be
performed, and hereby guarantees the performance of, all actions, agreements and
obligations set forth herein to be performed by any Subsidiary of such party or
by any entity that is contemplated to be a Subsidiary of such party on and after
the Distribution Date.

     SECTION 11.13 THIRD PARTY BENEFICIARIES. This Agreement is solely for the
benefit of the parties hereto and their respective Subsidiaries and Affiliates
and shall not be deemed to confer upon third parties any remedy, claim,
liability, reimbursement, claim of action, accelerated entitlement to any
compensation or benefit, or other right.

     SECTION 11.14 FIDUCIARY MATTERS; CONSENT OF THIRD PARTIES. IMPCO and
Quantum each acknowledge that actions required to be taken pursuant to this
Agreement may be subject to fiduciary duties or standards of conduct under ERISA
or other applicable law, and no party shall be deemed to be in violation of this
Agreement if it fails to comply with any provisions hereof based upon its good
faith determination that to do so would

                                       14

<PAGE>

violate such a fiduciary duty or standard. If any provision of this Agreement is
dependent on the consent of any third party and such consent is withheld, IMPCO
and Quantum shall use their reasonable best efforts to implement the applicable
provisions of this Agreement to the full extent practicable. If any provision of
this Agreement cannot be implemented due to the failure of such third party to
consent, IMPCO and Quantum shall negotiate in good faith to implement the
provision in a mutually satisfactory manner.

     SECTION 11.15 TITLE AND HEADINGS. Titles and headings to sections herein
are inserted for the convenience of reference only and are not intended to be a
part of or to affect the meaning or interpretation of this Agreement.

     SECTION 11.16 EXHIBITS AND SCHEDULES. The Exhibits and Schedules, if any,
shall be construed with and as an integral part of this Agreement to the same
extent as if the same had been set forth verbatim herein.

     SECTION 11.17 GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF CALIFORNIA APPLICABLE TO
CONTRACTS MADE AND TO BE PERFORMED IN THE STATE OF CALIFORNIA.

     SECTION 11.18 CONSENT TO JURISDICTION. Without limiting the provisions of
Article X hereof, each of the parties irrevocably submits to the exclusive
jurisdiction of (a) the Superior Court of the State of California, Los Angeles
County, and (b) the United States District Court for the Central District of
California, for the purposes of any suit, action or other proceeding arising out
of this Agreement or any transaction contemplated hereby. Each of the parties
agrees to commence any action, suit or proceeding relating hereto either in the
United States District Court for the Central District of California or if such
suit, action or other proceeding may not be brought in such court for
jurisdictional reasons, in the Superior Court of the State of California, Los
Angeles County. Each of the parties further agrees that service of any process,
summons, notice or document by U.S. registered mail to such party's respective
address set forth above shall be effective service of process for any action,
suit or proceeding in California with respect to any matters to which it has
submitted to jurisdiction in this Section 11.18. Each of the parties irrevocably
and unconditionally waives any objection to the laying of venue of any action,
suit or proceeding arising out of this Agreement or the transactions
contemplated hereby in (i) Superior Court of the State of California, Los
Angeles County, or (ii) the United States District Court for the Central
District of California, and hereby further irrevocably and unconditionally
waives and agrees not to plead or claim in any such court that any such action,
suit or proceeding brought in any such court has been brought in an inconvenient
forum.

     SECTION 11.19 SEVERABILITY. In the event any one or more of the provisions
contained in this Agreement should be held invalid, illegal or unenforceable in
any respect, the validity, legality and enforceability of the remaining
provisions contained herein and therein shall not in any way be affected or
impaired thereby. The parties shall endeavor in good-faith negotiations to
replace the invalid, illegal or unenforceable provisions with valid provisions,
the economic effect of which comes as close as possible to that of the invalid,
illegal or unenforceable provisions.

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<PAGE>

     SECTION 11.20 GOVERNMENTAL NOTICES; COOPERATION. Notwithstanding anything
in this Agreement to the contrary, all actions contemplated herein with respect
to Employee Benefit Plans which are to be consummated pursuant to this Agreement
shall be subject to such notices to, and/or approvals by, the Service (or any
other governmental agency or entity) as are required or deemed appropriate by
such Employee Benefit Plan's sponsor. Each of IMPCO and Quantum agrees to use
its commercially reasonable efforts to cause all such notices and/or approvals
to be filed or obtained, as the case may be. Each party hereto shall reasonably
cooperate with the other parties with respect to any government filings,
employee notices or any other actions reasonably necessary to maintain and
implement the Employee Benefit Plans covered by this Agreement.

     SECTION 11.21 FURTHER ASSURANCES. From time to time, as and when reasonably
requested by any other party hereto, each party hereto shall execute and
deliver, or cause to be executed and delivered, all such documents and
instruments and shall take, or cause to be taken, all such further or other
actions as such other party may reasonably deem necessary or desirable to effect
the purposes of this Agreement and the transactions contemplated hereunder.

     IN WITNESS WHEREOF, the parties have duly executed and entered into this
Agreement, as of the date first above written.


                                IMPCO TECHNOLOGIES, INC.

                                By:   /s/ Robert M. Stemmler
                                   ---------------------------------------------
                                   Name:  Robert M. Stemmler
                                   Title: President and Chief Executive Officer


                                QUANTUM FUEL SYSTEMS
                                TECHNOLOGIES WORLDWIDE, INC.

                                By:  /s/ Alan P. Niedzwiecki
                                   --------------------------------------------
                                   Name:  Alan P. Niedzwiecki
                                   Title: President and Chief Operating Officer

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<PAGE>

                                 Schedule 5.1(b)

The exercise prices for each IMPCO Adjusted Option and Quantum Option will be
determined as follows:

     1. Calculate the aggregate intrinsic value of the IMPCO Option immediately
prior to the Distribution and determine the ratio of the exercise price for the
IMPCO Option to the market value of IMPCO Common Stock immediately prior to the
Distribution (the "Pre-Distribution Exercise Price to Market Price Ratio").

     2. Calculate the preliminary IMPCO Adjusted Option exercise price by
dividing (x) the market value of IMPCO Common Stock (without Quantum)
immediately after the Distribution by (y) the sum of (i) the market value of
IMPCO Common Stock immediately after the Distribution and (ii) the market value
of Quantum Common Stock immediately after the Distribution multiplied by the
Distribution Ratio, and multiplying the result by the exercise price for the
IMPCO Option.

     3. Divide the preliminary IMPCO Adjusted Option exercise price by the
market value of IMPCO Common Stock immediately after the Distribution to
determine the "IMPCO Adjusted Exercise Price to Market Price Ratio." If the
IMPCO Adjusted Exercise Price to Market Price Ratio is less than the
Pre-Distribution Exercise Price to Market Price Ratio, increase the preliminary
IMPCO Adjusted Option exercise price to align the IMPCO Adjusted Exercise Price
to Market Ratio with the Pre-Distribution Exercise Price to Market Price Ratio
in order to determine the final Adjusted IMPCO Option exercise price.

     4. Calculate the preliminary Quantum Option exercise price by multiplying
the exercise price for the IMPCO Option by the result obtained by dividing (z)
one minus the fraction calculated in paragraph 2 above by (w) the Distribution
Ratio.

     5. Divide the preliminary Quantum Option exercise price by the market value
of Quantum Common Stock immediately after the Distribution to determine the
"Quantum Adjusted Exercise Price to Market Price Ratio." If the Quantum Adjusted
Exercise Price to Market Ratio is less than the Pre-Distribution Exercise Price
to Market Price Ratio, increase the preliminary Quantum Option exercise price to
align the Quantum Adjusted Exercise Price to Market Price Ratio with the
Pre-Distribution Exercise Price to Market Price Ratio in order to determine the
final Quantum Option exercise price.

     6. Add the aggregate intrinsic values of the Adjusted IMPCO Option and
Quantum Option and compare the sum to the aggregate intrinsic value calculated
in paragraph 1 above and make final adjustments, if necessary, so that the
aggregate intrinsic values of the Adjusted IMPCO Option and Quantum Option do
not exceed the original aggregate intrinsic value of the IMPCO Option.

                                       17