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                                                                EXHIBIT 10.2

                  TAX ALLOCATION AND INDEMNIFICATION AGREEMENT

     This TAX ALLOCATION AND INDEMNIFICATION 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") (each, individually a "Party," and
collectively, the "Parties").

     WHEREAS, IMPCO, acting directly and through its subsidiaries, currently
conducts a number of businesses, including, without limitation, (i) the Gaseous
Fuel Products Business (as defined in the Distribution Agreement), (ii) the
Automotive OEM Business (as defined in the Distribution Agreement), and (iii)
the International Business (as defined in the Distribution Agreement);

     WHEREAS, 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"), to restructure IMPCO to separate from IMPCO
            ------------------
the Automotive OEM Business and to cause such business to be owned and
conducted, directly or indirectly, by Quantum;

     WHEREAS, in order to effect the 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 IMPCO Common Stock, for
IMPCO to take certain steps to reorganize IMPCO's Subsidiaries (as defined
herein) and businesses and upon the completion of such reorganization 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
                                                              --------------
Shares") as set forth in that certain Contribution and Distribution Agreement
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dated as of July 23, 2002 between IMPCO and Quantum (the "Distribution
                                                          ------------
Agreement");
---------

     WHEREAS, as a result of the Distribution (as defined in the Distribution
Agreement), the Quantum Group will not be included in the consolidated federal
Income Tax Return of IMPCO for the portion of the year following the
Distribution and in future years; and

     WHEREAS, IMPCO and Quantum desire to allocate the Tax (as defined herein)
burdens and benefits of transactions which occurred on or prior to the
Distribution Date (as defined herein) and to provide for certain other Tax
matters, including the assignment of responsibility for the preparation and
filing of Tax Returns (as defined herein), the payment of Taxes, and the
prosecution and defense of any Tax controversies.

     NOW, THEREFORE, in consideration of the mutual agreements, provisions and
covenants contained in this Agreement, the Parties hereby agree as follows:

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                                    ARTICLE I
                                   DEFINITIONS

SECTION 1.1. GENERAL.

     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:

     (a) "Award" means stock options issued to a single person that have the
same date of grant and exercise price.

     (b) "Basic Research Payments" shall have the meaning set forth in Section
41(e)(2) of the Code.

     (c) "Code" shall mean the U.S. Internal Revenue Code of 1986, as amended,
and the Treasury regulations promulgated thereunder, including any successor
legislation.

     (d) "Combined Returns" shall mean all state Income Tax Returns with respect
to which IMPCO files on a combined or unitary basis with some or all of its
Subsidiaries.

     (e) "Consolidated Returns" shall mean all consolidated federal Income Tax
Returns of the affiliated group of which IMPCO is the common parent.

     (f) "Controlled Entity" 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 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).

     (g) "Crossover Option" shall have the meaning set forth in Section 5.3(b).

     (h) "Definitive Guidance" means temporary or final Treasury regulations, a
Revenue Ruling, Revenue Procedure or Notice issued by the Internal Revenue
Service or a final decision of the United States Tax Court.

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

     (j) "Final Determination" shall mean the final resolution of liability for
any Tax for any taxable period, including any related interest or penalties, by
or as a result of: a final and unappealable decision, judgment, decree or other
order by any court of competent jurisdiction; (ii) a closing agreement or
accepted offer in compromise under Section 7121 or 7122 of the Code, or
comparable agreement under the laws of other jurisdictions which resolves the
entire Tax liability for any taxable period; (iii) any allowance of a refund or
credit in respect of an overpayment of Tax, but only after the expiration of all
periods during which such refund may be

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recovered by the jurisdiction imposing the Tax; or (iv) any other final
disposition, including by reason of the expiration of the applicable statute of
limitations.

     (k) "Foreign Taxes shall mean any Taxes imposed by a foreign Governmental
Authority.

     (l) "Foreign Tax Return" means any Tax Return filed with a foreign
Governmental Authority.

     (m) "Franchise Tax Returns" shall mean all franchise Tax Returns of the
Pre-Distribution IMPCO Group or any member thereof.

     (n) "Governmental Authority" shall mean any federal, state, local, foreign
or international court, government, department, commission, board, bureau,
agency, official or other regulatory, administrative or governmental authority.

     (o) "Gross Receipts" shall have the meaning set forth in Section 41(c)(6)
of the Code.

     (p) "Included Party" shall have the meaning as defined in Section 2.3.

     (q) "Income Tax Return" shall mean any Tax Return relating to Income Taxes.

     (r) "Income Taxes" shall mean any federal, state or local Taxes determined
by reference to income or imposed in lieu of income Taxes, such as Taxes based
on net worth or gross receipts.

     (s) "Indemnifying Party" shall have the meaning as defined in Section 3.4.

     (t) "Indemnitee" shall have the meaning as defined in Section 3.4.

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

     (v) "IMPCO Business" shall mean each and every business conducted at any
time by IMPCO or any Subsidiary of IMPCO prior to the Effective Time, excluding
the Quantum Business.

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

     (x) "IMPCO Option" means an option to acquire stock of IMPCO.

     (y) "IMPCO Optionee" means a person who at the time of the exercise of a
Replacement Option (i) is employed by or otherwise providing services to a
member of the IMPCO Group, or (ii) is not employed by or otherwise providing
services to a member of either the IMPCO Group or the Quantum Group but who
previously was employed by or otherwise provided services to a member of the
IMPCO Group and after the termination of such relationship did not become
employed by or otherwise provide services to a member of the Quantum Group.

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     (z) "Non-Combined Returns" shall mean all state and local Income Tax
Returns (other than Combined Returns), of the Pre-Distribution IMPCO Group or
any member thereof.

     (aa) "Nonperforming Party" shall have the meaning as defined in Section
6.2.

     (ab) "Other Taxes" shall mean all Taxes other than Taxes covered by a
Consolidated Return, a Combined Return, a Non-Combined Return, a Franchise Tax
Return or a Foreign Tax Return.

     (ac) "Partnership" shall mean any entity classified as a partnership for
U.S. federal income tax purposes.

     (ad) "Party" or "Parties" shall have the meanings as defined in the
recitals hereto.

     (ae) "Person" shall mean any natural person, corporation, business trust,
joint venture, association, company, partnership or government, or any agency or
political subdivision thereof.

     (af) "Pre-Distribution IMPCO Group" shall mean IMPCO and all of its
Subsidiaries (direct and indirect, domestic and foreign) prior to the
Distribution, including Quantum.

     (ag) "Preparing Party" shall have the meaning as defined in Section 2.3.

     (ah) "Restructuring" shall mean the series of contributions and
distributions of Controlled Entities and assets, transfers and assumptions of
liabilities, and other transactions whereby the IMPCO Group and the Quantum
Group are formed and all other Controlled Entities of IMPCO prior to the
Distribution are placed under the control of the appropriate parent
corporation(s) in connection with the Distribution.

     (ai) "Qualified Research Expenses" shall have the meaning set forth in
Section 41(b) of the Code.

     (aj) "Quantum Assets" shall have the meaning set forth in the Distribution
Agreement.

     (ak) "Quantum Business" shall have the meaning set forth in the
Distribution Agreement.

     (al) "Quantum Group" shall mean Quantum and each business entity which is
contemplated to remain or become a Subsidiary of Quantum under the Distribution
Agreement, which shall include those identified on Schedule 1.1(ppp) to the
Distribution Agreement.

     (am) "Quantum Option" means an option to acquire stock of Quantum.

     (an) "Quantum Optionee" means a person who at the time of the exercise of a
Replacement Option (i) is employed by or otherwise providing services to a
member of the Quantum Group, or (ii) is not employed by or otherwise providing
services to a member of either the Quantum Group or the IMPCO Group but who
previously was employed by or otherwise provided services to a member of the
Quantum Group and after the termination of such

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relationship did not become employed by or otherwise provide services to a
member of the IMPCO Group.

     (ao) "Replacement Option" means (i) an option to acquire stock of IMPCO or
an option to acquire stock of Quantum which option was issued pursuant to
Article V of the Employee Matters Agreement or in connection with the
Distribution, or (ii) an option that is issued in exchange for an option
described in clause (i) or (ii) of this definition.

     (ap) "Research Credit" means the research credit determined under Section
41 of the Code.

     (aq) "Subsidiary" shall mean any entity of which another entity's ownership
satisfies the 80-percent voting and value test defined in Section 1504(a)(2) of
the Code, whether directly or indirectly.

     (ar) "Tax" or "Taxes" whether used in the form of a noun or adjective,
shall mean taxes on or measured by income, franchise, gross receipts, sales,
use, excise, payroll, personal property, real property, ad-valorem, value-added,
leasing, leasing use or other taxes, levies, imposts, duties, charges or
withholdings of any nature (including, without limitation, any liability under
Treasury Regulations Section 1.1502-6 or any comparable provision of foreign,
state or local law). Whenever the term "Tax" or "Taxes" is used (including,
without limitation, regarding any duty to reimburse another Party for
indemnified taxes or refunds or credits of taxes) it shall include penalties,
fines, additions to tax and interest thereon.

     (as) "Tax Item" shall mean any item of income, capital gain, net operating
loss, capital loss, deduction, credit or other Tax attribute relevant to the
calculation of a Tax liability.

     (at) "Tax Matters Partner" shall mean the tax matters partner as defined in
Section 6231(a)(7) of the Code.

     (au) "Tax Returns" shall mean all reports or returns (including information
returns) required to be filed or that may be filed for any period with any
Governmental Authority (whether domestic or foreign) in connection with any Tax
or Taxes (whether domestic or foreign).

     (av) "Transferred Business" shall have the meaning set forth in Section
4.4.

SECTION 1.2. REFERENCES; INTERPRETATION.

     References in this Agreement to any gender include references to all
genders, and references to the singular include references to the plural and
vice versa. The words "include," "includes" and "including" when used in this
Agreement shall be deemed to be followed by the phrase "without limitation."
Unless the context otherwise requires, references in this Agreement to Articles,
Sections, Exhibits and Schedules shall be deemed references to Articles and
Sections of, and Exhibits and Schedules to, such Agreement. Unless the context
otherwise requires, the words "hereof," "hereby" and "herein" and words of
similar meaning when used in this

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Agreement refer to this Agreement in its entirety and not to any particular
Article, Section or provision of this Agreement.

                                   ARTICLE II
                      PREPARATION AND FILING OF TAX RETURNS

SECTION 2.1. PREDISTRIBUTION TAX RETURNS.

     (a) Notwithstanding anything herein to the contrary, IMPCO shall prepare
and file all Tax Returns due on or before the Distribution Date.

     (b) IMPCO shall prepare and file (i) all Consolidated Returns, Combined
Returns, Non-Combined Returns, and Franchise Tax Returns that are not filed
prior to the Distribution Date and (ii) any Tax Returns of any Partnership of
which IMPCO or any Subsidiary is the Tax Matters Partner if a distributive share
of Partnership income, gain loss or deduction is included in any such Tax
Return.

     (c) All Tax Returns for Other Taxes for periods beginning prior to the
Distribution Date shall be prepared and filed by Quantum if they relate to any
Quantum Business, and otherwise, by IMPCO.

     (d) All Foreign Tax Returns that are required to be filed by or relating to
any member of the Pre-Distribution IMPCO Group for periods beginning before the
Distribution Date shall be prepared and filed by the entity that filed the
corresponding Tax Return for the most recent period for which such a Tax Return
has been filed, or, if no such corresponding Tax Return has been filed, by the
appropriate entity in accordance with local law or custom.

SECTION 2.2. POST-DISTRIBUTION TAX RETURNS.

     (a) The filing of all Tax Returns for periods beginning on or after the
Distribution Date shall be the responsibility of IMPCO if they relate to the
IMPCO Group or any member thereof and shall be the responsibility of Quantum if
they relate to the Quantum Group or any member thereof.

     (b) In the case of any Partnership in which a member of the
Pre-Distribution IMPCO Group is the designated Tax Matters Partner, such entity
shall continue to be responsible for the preparation and filing of such
Partnership's Tax Returns.

SECTION 2.3. MANNER OF PREPARATION.

     (a) To the extent any Tax Return includes Taxes relating to a Party (or any
of its Subsidiaries) other than the Party preparing such Tax Return (the
"Preparing Party"), the Party not responsible for preparing the Tax Return (the
"Included Party"), upon request by the Preparing Party, shall prepare and
deliver to the Preparing Party, at least 60 days prior to the due date
(including extensions) of such Tax Return, a true and correct accounting of all
relevant Tax Items so requested relating to the Included Party (and any of its
Subsidiaries) for the taxable period.

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     (b) All Tax Returns filed on or after the Distribution Date shall be
prepared on a basis that is consistent with the tax opinion obtained from
Morrison & Foerster LLP in connection with the Distribution (in the absence of a
controlling change in law or circumstances) and shall be filed on a timely basis
(including pursuant to extensions) by the Party responsible for such filing
under this Agreement. In the absence of a controlling change in law or
circumstances and unless deviation from past practice would have no adverse
effect on the other Party, all Tax Returns filed within three years after the
Distribution Date shall be prepared on a basis consistent with the elections,
accounting methods, conventions, assumptions and principles of taxation used for
the most recent taxable periods for which Tax Returns involving similar Tax
Items have been filed; provided, however, that a Party preparing any Tax Return
that does not conform to such past practices shall not be liable for any
additional Tax liability imposed on the other Party, in whole or in part, as a
result of such deviation from past practice if: (i) 30 days prior to the filing
of such Tax Return, the Party preparing such Tax Return notifies the other Party
if such other Party may be adversely affected; and (ii) the Party preparing such
Tax Return establishes that conformity with past practice involves a significant
risk of the imposition of a penalty. Subject to the provisions of this
Agreement, all decisions relating to the preparation of Tax Returns shall be
made in the sole discretion of the Party responsible under this Agreement for
its preparation; provided, however, that the "Included Party" shall have the
right to review and comment on such Tax Return prior to the filing thereof in
the following manner:

     The Preparing Party shall submit any part of such Tax Return relating to
the Included Party (or any of its Subsidiaries) to the Included Party at least
14 days prior to the date on which such Tax Return is due (including
extensions). The Included Party shall submit its comments to the Preparing Party
within 7 days of receipt of the relevant portions of such Tax Return. The
Preparing Party shall alter such Tax Return to reflect the reasonable comments
of the Included Party unless the Preparing Party reasonably believes that such
alteration would have an adverse impact upon the Preparing Party.

     (c) Unless otherwise required by any Governmental Authority, the Parties
hereby agree to file all Tax Returns, and to take all other actions, in a manner
consistent with the position that the Distribution Date is the last day on which
any member of the Quantum Group was included in the Pre-Distribution IMPCO
Group. For any period that includes but does not end on the Distribution Date,
to the extent permitted by law or administrative practice, the taxable year of
each Quantum Group member of the Pre-Distribution IMPCO Group and any group of
such members shall be treated as ending on the Distribution Date.

                                   ARTICLE III
                                PAYMENT OF TAXES

SECTION 3.1. PRE-DISTRIBUTION TAXES.

     (a) The Party responsible for the filing of any Tax Return pursuant to
Sections 2.1 and 2.2 shall pay to the relevant Governmental Authority all Taxes
due or payable in connection therewith; PROVIDED, that if, pursuant to this
Article III, one Party is liable for any Taxes relating to a Tax Return filed by
the other Party, upon request by such other Party, such non

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filing Party shall pay the filing Party the amount of such Taxes within thirty
(30) days of such request.

     (b) With respect to any Consolidated Return, Combined Return, Non-Combined
Return or Franchise Tax Return for a taxable period ending before May 1, 2001
that is not filed prior to the Distribution Date, IMPCO shall be liable for all
Taxes payable with such Tax Return and shall be entitled to any refund or credit
for an overpayment of Taxes shown on such Tax Return. Except as otherwise
provided in Section 3.2 hereof, with respect to any Consolidated Return,
Combined return, Non-Combined Return or Franchise Tax Return for a taxable
period beginning on or after May 1, 2001, IMPCO shall be liable for all Taxes
payable with such Tax Return that are attributable to the portion of such
taxable period up to and including the Distribution Date and that exceed the
amount of Taxes paid in respect of such taxable period (as estimated Taxes or
otherwise) on or prior to the Distribution Date and (ii) shall be entitled to
any refund or credit of Taxes to the extent Taxes paid in respect of such
taxable period (as estimated Taxes or otherwise) on or prior to the Distribution
Date exceed the amount of Taxes attributable to the portion of the period up to
and including the Distribution Date. The determination of the amount of Taxes
attributable to the portion of such taxable period up to and including the
Distribution Date shall be done on the basis of a closing of the books of IMPCO
as of the Distribution Date, except that Tax Items calculated on an annual basis
shall be apportioned based on the percentage of the actual period to which such
taxes relate that precedes the Distribution Date.

     (c) In the event of any Final Determination adjusting the amount of any
Taxes that are the subject of a Consolidated Return, Combined Return,
Non-Combined Return or Franchise Tax Return, Quantum shall be liable for its
share of any increases in Taxes and shall be entitled to its share of any
refunds or credits of Taxes, and IMPCO shall be liable for all other increases
in Taxes and shall be entitled to all other refunds or credits of Taxes, all in
accordance with the principles of Sections 3.1(a) and (b) above.

     (d) IMPCO shall be liable for all Other Taxes that are attributable to the
IMPCO Business and Quantum shall be liable for all Other Taxes that are
attributable to the Quantum Business.

     (e) In the case of any Consolidated Return, Combined Return, Non-Combined
Return or Franchise Tax Return with respect to which IMPCO has responsibility
for any Taxes or is entitled to any refunds or credits of Taxes pursuant to this
Section 3.1, IMPCO shall have the right to prepare an amended Tax Return.
Quantum shall be required to sign and file any such amended Tax Return, as
necessary. IMPCO shall be entitled to any refunds or credits of Taxes relating
to any such amended Tax Return.

     (f) The entity responsible for the filing of any Foreign Tax Return
pursuant to Section 2.1(c) shall pay to the relevant Governmental Authority all
Taxes due or payable (or receive all refunds) in connection therewith; PROVIDED,
HOWEVER, that each of the Parties shall be liable for all Foreign Taxes (or be
entitled to receive all refunds) for all taxable periods beginning prior to the
Distribution Date, including audit adjustments thereto, relating to such Party's
business. To the extent any Foreign Tax Return includes Taxes relating to a
business other than the Preparing Party's business, the Included Party shall
prepare and deliver to the

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Preparing Party, at least 30 days prior to the due date (including extensions)
of such Foreign Tax Return, a true and correct accounting of all relevant Tax
Items and corresponding Taxes relating to the Included Party's business for the
taxable period ("Separate Business Foreign Taxes") and shall pay the Preparing
Party the amount of any such Separate Business Foreign Taxes at that time.
Separate Business Foreign Taxes shall be calculated as if the Included Party's
business were a separate taxpayer for the relevant taxable period. All such
calculations shall be based upon the business's actual Tax attributes for the
relevant taxable period, including the use of the business's Tax attributes
(such as losses or credits) from prior periods that are not otherwise utilized
and that are carried over to the relevant taxable period under local law.

         (i) If the total liability for Taxes reported as due and payable on the
relevant Foreign Tax Return exceeds or is less than the total of the Separate
Business Foreign Taxes for all businesses included in such Foreign Tax Return,
then the cost or benefit of any net difference shall be allocated to each
business in proportion to the amount of taxable income generated by such
business.

         (ii) Notwithstanding any statement to the contrary in this Section
3.1(f), the Separate Business Foreign Taxes of any entity shall not exceed the
total liability for Taxes reported as due and payable on the relevant Foreign
Tax Return.

         (iii) In the event of any Final Determination upholding an audit
adjustment to the amount of Foreign Taxes reported as due and payable on the
relevant Foreign Tax Return, Separate Business Foreign Taxes shall be
recalculated to incorporate any such adjustment.

SECTION 3.2. POST-DISTRIBUTION TAXES.

     Unless otherwise provided in this Agreement (except with respect to Section
3.1, which shall be subject to this Section 3.2 to the extent inconsistent
herewith):

     (a) IMPCO shall pay all Taxes and shall be entitled to receive and retain
all refunds of Taxes:

         (i) with respect to a Consolidated Return, Combined Return,
Non-Combined Return or Franchise Tax Return for a taxable period that begins
prior to the Distribution Date and includes but does not end on the Distribution
Date to the extent such Taxes or refunds are attributable to (y) the portion of
such period after the Distribution Date and (z) the IMPCO Group or any member
thereof; and

         (ii) with respect to periods beginning on or after the Distribution
Date that are attributable to the IMPCO Group or any member thereof.

     (b) Quantum shall pay all Taxes and shall be entitled to receive and retain
all refunds of Taxes:

         (i) with respect to a taxable period that begins prior to the
Distribution Date, and includes but does not end on the Distribution Date, to
the extent such Taxes or refunds are

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attributable to (y) the portion of such period after the Distribution Date and
(z) the Quantum Group or any member thereof; and

         (ii) with respect to periods beginning on or after the Distribution
Date that are attributable to the Quantum Group or any member thereof; including
any such Taxes relating to a Combined Return described in Section 2.2(a) hereof.

SECTION 3.3. RESTRUCTURING AND DISTRIBUTION TAXES.

     (a) Notwithstanding any statement to the contrary in this Agreement, and
except as otherwise provided in the Distribution Agreement, to the extent that
any Taxes are found to arise out of the Restructuring, then any such Tax
liability incurred by the Parties (or any of their Subsidiaries) shall be the
responsibility of Quantum, regardless of the Party primarily liable for such
Taxes under the applicable Tax laws, provided that any liability for Taxes
arising in connection with the application of Section 357(c) of the Code shall
be the responsibility of IMPCO.

     (b) Notwithstanding any statement herein to the contrary, any Taxes
relating to or arising out of the Distribution shall be governed by Section 2.11
of the Distribution Agreement; PROVIDED, HOWEVER, that the provisions of Article
V of this Agreement shall control to the extent inconsistent with the provisions
of the Distribution Agreement.

SECTION 3.4. INDEMNIFICATION.

     (a) Indemnification by IMPCO. IMPCO shall indemnify, defend and hold
harmless Quantum (and its affiliates) from and against any and all Tax
liabilities allocated to IMPCO by this Agreement, the Employee Benefit Matters
Agreement or the Distribution Agreement.

     (b) Indemnification by Quantum. Quantum shall indemnify, defend and hold
harmless IMPCO (and its affiliates) from and against any and all Tax liabilities
allocated to Quantum by this Agreement, the Employee Benefit Matters Agreement
or the Distribution Agreement.

     (c) Indemnity Payments.
         ------------------

         (i) To the extent that one Party (the "Indemnifying Party") owes money
to another Party (the "Indemnitee") pursuant to this Section 3.4, the Party (the
"Notifying Party") having knowledge of such obligation shall notify the other
Party and shall provide such other Party with its calculations of such
obligation (as specified in Articles I and III hereof). The other Party, within
14 days after receiving the Notifying Party's calculations, shall submit to the
Notifying Party such other Party's calculations of the amount required to be
paid pursuant to this Section 3.4, showing such calculations in sufficient
detail so as to permit the Notifying Party to understand the calculations. The
Indemnifying Party shall pay the Indemnitee, no later than the later of 5 days
prior to the due date (including extensions) of the relevant Tax Returns and 14
days after the Notifying Party receives the other Party's calculations, the
amount for which the Indemnifying Party is required to pay or indemnify the
Indemnitee under this Section 3.4. The

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     Indemnifying Party shall have the right to disagree with the Indemnitee's
     calculations. Any dispute regarding such calculations shall be resolved in
     accordance with Section 6.4 of this Agreement.

         (ii) All indemnity payments shall be calculated on a pre-Tax basis and,
unless otherwise required by law, shall be treated as contributions to capital
and/or dividends immediately prior to the Distribution.

                                   ARTICLE IV
                                 TAX ATTRIBUTES

SECTION 4.1. CARRYBACKS.

     In the event of the realization of any deduction, loss or credit by a Party
for any taxable period beginning on or after the Distribution Date, the Party
realizing such deduction, loss or credit may, in its sole discretion, and to the
extent permitted under applicable Tax law, elect to either carry back or carry
forward such deduction, loss or credit. Any refund attributable to such
carryback shall be allocable to such Party. In the event both Parties elect to
carry back an amount to the same taxable period beginning prior to the
Distribution Date, any refund shall be apportioned between the Parties based on
the relative carryback amounts.

SECTION 4.2. COMPETENT AUTHORITY RELIEF.

     If as a result of any audit of a taxable period beginning prior to the
Distribution Date, a Party (or a Subsidiary thereof) is required to adjust its
income, deductions, credits or allowances under Section 482 of the Code or under
similar principles in a foreign jurisdiction, and the payment of additional
Taxes in accordance with such a determination allows the other Party (or
Subsidiary) to obtain competent authority relief as a result thereof, then the
Party eligible to obtain such relief shall (a) execute or cause to be executed
any powers of attorney or other documents necessary to enable the other Party to
pursue such relief at its own expense; and (b) cooperate with the other Party
and the competent authorities in seeking such relief.

SECTION 4.3. EARNINGS AND PROFITS.

     The Parties agree to allocate the Pre-Distribution IMPCO Group's "earnings
and profits" (as determined for federal income tax purposes), if any, between
the between the IMPCO Group and the Quantum Group based upon the relative
closing prices for IMPCO common stock and Quantum common stock on the NASDAQ
National Market on the Distribution Date.

SECTION 4.4. RESEARCH CREDITS.

     For purposes of determining each Party's Research Credits for taxable
periods ending after the Distribution Date with respect to Qualified Research
Expenses and Basic Research Payments incurred or made by them after the
Distribution Date and pursuant to Section 41(f)(3) of the Code, the Parties
agree to treat the Distribution as the acquisition by Quantum of a major portion
of a trade or business of IMPCO and the disposition of such portion by IMPCO
with


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respect to the transfer of the Quantum Business and the Quantum Assets (the
"Transferred Business") from IMPCO to Quantum in connection with the
Distribution. In connection therewith and in accordance with Section 41(f)(3) of
the Code: (a) Quantum shall increase its Qualified Research Expenses and Gross
Receipts for periods prior to the Distribution Date by so much of the Qualified
Research Expenses and Gross Receipts of IMPCO that are attributable to the
Transferred Business for such periods, as reasonably determined by IMPCO, (b)
IMPCO shall decrease its Qualified Research Expenses and Gross Receipts for
periods prior to the Distribution Date by the amounts of IMPCO's Qualified
Research Expenses and Gross Receipts described in clause (a), and (c) IMPCO
shall provide Quantum with the information necessary for Quantum to comply with
Section 41(f)(3)(A) of the Code. Notwithstanding anything herein to the
contrary, the IMPCO Group shall retain all of its Research Credit carryovers
from all periods prior to the Distribution Date and no portion of such Research
Credit carryovers shall be allocated or attributed to the Quantum Group.

                                   ARTICLE V
                           COMPENSATORY STOCK OPTIONS

SECTION 5.1. IMPCO DEDUCTIONS.

     Notwithstanding anything herein or in an Ancillary Agreement to the
contrary:

     (a) All compensation deductions attributable to the amounts included in the
gross income of an IMPCO Optionee whether such amounts of gross income are
attributable to the exercise of an IMPCO Option or a Quantum Option shall be
allocated to and claimed by the IMPCO Group and the Quantum Group shall not
report such deductions on its Income Tax Returns.

     (b) All compensation deductions attributable to the amounts included in the
gross income of a Quantum Optionee as a result of the exercise of a Quantum
Option or IMPCO Option after the Distribution Date shall be allocated to and
claimed by the Quantum Group and the IMPCO Group shall not report such
deductions on its Income Tax Returns.

SECTION 5.2. WITHHOLDING AND INFORMATION REPORTING.

     (a) Notwithstanding anything herein or in an Ancillary Agreement to the
contrary, (i) IMPCO shall be responsible for any payroll Taxes, withholding
Taxes and information reporting arising out of the exercise of an IMPCO Option
or a Quantum Option by an IMPCO Optionee, and (ii) Quantum shall be responsible
for any payroll Taxes, withholding Taxes and information reporting arising out
of the exercise of an IMPCO Option or a Quantum Option by a Quantum Optionee.

     (b) With respect to any Quantum Option held by an IMPCO Optionee, and with
respect to any IMPCO Option held by a Quantum Optionee, (each, a "Crossover
Option"), such entity as mutually designated by IMPCO and Quantum shall act as
the recordkeeper for the Crossover Options. If the exercise of Crossover Options
is made pursuant to a broker-assisted cashless exercise through the recordkeeper
in accordance with the regulations of the Federal Reserve Board, then
immediately after such exercise, the recordkeeper shall sell the number of
shares necessary to remit the following payments (which may be all the shares):
(i) to the issuer of the option, the exercise price; and (ii) to the employer of
the option holder, the employee's share of income and payroll taxes. The
recordkeeper shall thereafter remit to the option holder (i) the balance of the
proceeds from the sale of all shares or (ii) the remaining whole shares and cash
for any fractional shares, as applicable.

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cashless exercise through the recordkeeper in accordance with the regulations of
the Federal Reserve Board, then immediately after such exercise, the
recordkeeper shall sell the number of shares necessary to remit the following
payments (which may be all the shares): (i) to the issuer of the option, the
exercise price; and (ii) to the employer of the option holder, the employee's
share of income and payroll taxes. The recordkeeper shall thereafter remit to
the option holder (i) the balance of the proceeds from the sale of all shares or
(ii) the remaining whole shares and cash for any fractional shares, as
applicable.

SECTION 5.3. COOPERATION.

     IMPCO and Quantum agree to act (or to take such action) with respect to
such compensation deductions, and with respect to fulfilling the payroll Tax,
withholding Tax and information reporting obligations, consistent with Sections
5.1 through 5.2 above, as are reasonably necessary or appropriate to achieve,
maintain and/or preserve such tax results.

                                   ARTICLE VI
                   TAX AUDITS, TRANSACTIONS AND OTHER MATTERS

SECTION 6.1. TAX AUDITS AND CONTROVERSIES.

     In the case of any audit, examination or other proceeding ("Proceeding")
brought against a Party (or a Subsidiary thereof) with respect to Taxes for
which the other Party is or may be liable pursuant to this Agreement, the Party
subject to such Proceeding shall promptly inform such other Party and shall
execute or cause to be executed any powers of attorney or other documents
necessary to enable the other Party to take all actions desired with respect to
such Proceeding to the extent such Proceeding may affect the amount of Taxes for
which the other Party is liable pursuant to this Agreement. Each Party shall
have the right to control, at its own expense, the portion of any such
Proceeding that relates to Taxes for which such Party is or may be liable
pursuant to this Agreement; PROVIDED, HOWEVER, that such Party shall consult
with the other Party with respect to any issue that may affect the other Party
(or such Subsidiary). The Party in control of such Proceeding or any part
thereof shall not enter into any final settlement or closing agreement that may
adversely affect the other Party (or such Subsidiary) without the consent of
such other Party, which consent may not unreasonably be withheld. Where consent
to any final settlement or closing agreement is withheld, the Party withholding
consent shall continue or initiate further proceedings, at its own expense, and
the liability of the Party in control of such Proceeding shall not exceed the
liability that would have resulted from the proposed closing agreement or final
settlement (including interest, additions to Tax and penalties which have
accrued at that time).

SECTION 6.2. COOPERATION.

     IMPCO and Quantum shall cooperate with each other and any Governmental
Authority regarding all Tax matters, including, but not limited to, the filing
of any Tax Returns or claims for refund and the conduct of any audit or other
proceeding, and each shall execute and deliver such powers of attorney and other
documents and make available such information, personnel and documents as are
necessary to carry out the intent of this Agreement. To the extent such
cooperation involves the services of officers, directors, employees, or agents
of a Party, such

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services shall be made available in accordance with the principles set forth in
Section 2.10 of the Distribution Agreement. Each Party agrees to notify the
other Party of any audit adjustment that does not result in Tax liability but
can reasonably be expected to affect Tax Returns of the other Party or any of
its Subsidiaries. Notwithstanding any other provision of this Agreement, if a
Party (the "Nonperforming Party") fails to give its full cooperation and use its
best efforts in the conduct of an audit or other proceeding as provided by this
Section 6.2, and such failure results in the imposition of additional Taxes for
the period or periods involved in the audit or other proceeding, the
Nonperforming Party shall be liable in full for such additional Taxes.

SECTION 6.3. RETENTION OF RECORDS; ACCESS.

     Beginning on the Distribution Date, IMPCO and Quantum shall, and shall
cause each of their Controlled Entities to:

     (a)     retain adequate records, documents, accounting data and other
information (including computer data) necessary for the preparation and filing
of all Tax Returns required to be filed by any member of the Pre-Distribution
IMPCO Group or any combination of such members and for any audits and litigation
relating to such Tax Returns or to any Taxes payable by any member of the
Pre-Distribution IMPCO Group or any combination of such members; and

     (b)     give to the other Party reasonable access to such records,
documents, accounting data and other information (including computer data) and
to its personnel and premises for the purpose of the review or audit of such
reports or returns to the extent relevant to an obligation or liability of a
Party under this Agreement and in accordance with the provisions of Article IV
of the Distribution Agreement.

The obligations set forth in Sections 6.3(a) and 6.3(b) hereof shall continue
until the final conclusion of any audit or litigation to which the records and
information relate or until expiration of all applicable statutes of
limitations, whichever is longer.

SECTION 6.4. DISPUTE RESOLUTION.

     Any dispute or claim arising out of, in connection with, or in relation to
the interpretation, performance, nonperformance, validity or breach of this
Agreement or otherwise arising out of, or in any way related to this Agreement,
shall be resolved in the manner set forth in Article VII of the Distribution
Agreement.

SECTION 6.5. CONFIDENTIALITY; OWNERSHIP OF INFORMATION; PRIVILEGED INFORMATION.

     The provisions of Article IV of the Distribution Agreement relating to
confidentiality of information, ownership of information, privileged information
and related matters shall apply with equal force to any records and information
prepared and/or shared by and between the Parties in carrying out the intent of
this Agreement.

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                                   ARTICLE VII
                                  MISCELLANEOUS

SECTION 7.1. COMPLETE AGREEMENT; CONSTRUCTION.

     This Agreement, including the Exhibits and Schedules, shall constitute the
entire agreement between the Parties with respect to the subject matter hereof
and shall supersede all previous negotiations, commitments and 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 7.2. 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 Party.

SECTION 7.3. SURVIVAL OF AGREEMENTS.

     Except as otherwise provided by this Agreement, all covenants and
agreements of the Parties contained in this Agreement shall survive the
Distribution Date.

SECTION 7.4. 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 7.5. NOTICES.

     All notices and other communications hereunder shall be in writing and hand
delivered or mailed by registered or certified mail (return receipt requested)
or sent by any means of electronic message transmission with delivery confirmed
(by voice or otherwise) 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:

             (i)    if to IMPCO, to:

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

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             with a copy to:

                    Morrison & Foerster LLP
                    555 West Fifth Avenue, Suite 3500
                    Los Angeles, CA 90013
                    Telecopy: (213) 892-5454
                    Attn: Jonathan F. Atzen, Esq.

             (ii)   if to Quantum, to:

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

SECTION 7.6.   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 7.7.   AMENDMENTS.

     Subject to the terms of Section 7.9 hereof, this Agreement may not be
modified or amended except by an agreement in writing signed by each of the
Parties hereto.

SECTION 7.8.   ASSIGNMENT.

     This Agreement shall not be assignable, in whole or in part, directly or
indirectly, by any Party hereto without the prior written consent of the other
Party hereto, and any attempt to assign any rights or obligations arising under
this Agreement without such consent shall be void.

SECTION 7.9.   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 7.10.  TERMINATION.

     This Agreement may be terminated at any time prior to the Effective Date by
and in the sole discretion of IMPCO as provided in Section 9.11 of the
Distribution Agreement. In the event of such termination, neither Party shall
have any liability of any kind to the Party or any other person. After the
Distribution, this Agreement may not be terminated except by an agreement in
writing signed by each of the Parties hereto.

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SECTION 7.11.  CONTROLLED ENTITIES.

     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 Controlled Entity of such Party or by any entity
that is contemplated to be a Controlled Entity of such Party on and after the
Distribution Date.

SECTION 7.12.  THIRD PARTY BENEFICIARIES.

     This Agreement is solely for the benefit of the Parties hereto and their
respective Subsidiaries and should not be deemed to confer upon third parties
any remedy, claim, liability, reimbursement, claim of action or other right in
excess of those existing without reference to this Agreement.

SECTION 7.13.  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 7.14.  EXHIBITS AND SCHEDULES.

The Exhibits and Schedules 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 7.15.  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 7.16.  CONSENT TO JURISDICTION.

Without limiting the provisions of Section 6.4 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 7.16. 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

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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 7.17.  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.

IN WITNESS WHEREOF, the parties have caused this Agreement to be duly executed
as of the day and year first above written.

                            IMPCO TECHNOLOGIES, INC.,
                            a Delaware Corporation

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

                            QUANTUM FUEL SYSTEMS
                            TECHNOLOGIES WORLDWIDE, INC.,
                            a Delaware Corporation

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

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