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                                                                  EXHIBIT 10.8.3

                                 PROMISSORY NOTE

$5,000.00                                                    As of July 18, 2005
                                                            Birmingham, Michigan

      Asia Automotive Acquisition Corporation (the "Maker") promises to pay to
the order of William R. Herren (the "Payee") the principal sum of Five Thousand
Dollars and No Cents ($5,000.00) in lawful money of the United States of
America, together with interest on the unpaid principal balance of this Note, on
the terms and conditions described below.

      1. Principal. The principal balance of this Note shall be repayable on the
earlier of (i) December 31, 2005 or (ii) the date on which Maker consummates an
initial public offering of its securities.

      2. Interest. The principal balance shall bear interest at the rate of four
percent per annum.

      3. Application of Payments. All payments shall be applied first to payment
in full of any costs incurred in the collection of any sum due under this Note,
including (without limitation) reasonable attorneys' fees, then to the payment
in full of any late charges and finally to the reduction of the unpaid principal
balance of this Note.

      4. Events of Default. The following shall constitute Events of Default:

            (a) Failure to Make Required Payments. Failure by Maker to pay the
principal of or accrued interest on this Note within five (5) business days
following the date when due.

            (b) Voluntary Bankruptcy, Etc. The commencement by Maker of a
voluntary case under the Federal Bankruptcy Code, as now constituted or
hereafter amended, or any other applicable federal or state bankruptcy,
insolvency, reorganization, rehabilitation or other similar law, or the consent
by it to the appointment of or taking possession by a receiver, liquidator,
assignee, trustee, custodian, sequestrator (or other similar official) of Maker
or for any substantial part of its property, or the making by it of any
assignment for the benefit of creditors, or the failure of Maker generally to
pay its debts as such debts become due, or the taking of corporate action by
Maker in furtherance of any of the foregoing.

            (c) Involuntary Bankruptcy, Etc. The entry of a decree or order for
relief by a court having jurisdiction in the premises in respect of Maker in an
involuntary case under the Federal Bankruptcy Code, as now or hereafter
constituted, or any other applicable federal or state bankruptcy, insolvency or
other similar law, or appointing a receiver, liquidator, assignee, custodian,
trustee, sequestrator (or similar official) of Maker or for any substantial part
of its property, or ordering the winding-up or liquidation of the affairs of
Maker, and the continuance of any such decree or order unstayed and in effect
for a period of 60 consecutive days.

      5. Remedies.

            (a) Upon the occurrence of an Event of Default specified in Section
4(a), Payee may, by written notice to Maker, declare this Note to be due and
payable, whereupon the principal amount of this Note, and all other amounts
payable thereunder, shall become immediately due and payable without
presentment, demand, protest or other notice of any kind, all of which are
hereby expressly waived, anything contained herein or in the documents
evidencing the same to the contrary notwithstanding.

            (b) Upon the occurrence of an Event of Default specified in Sections
4(b) and 4(c), the unpaid principal balance of, and all other sums payable with
regard to, this Note shall automatically and immediately become due and payable,
in all cases without any action on the part of Payee.

      6. Waivers. Maker and all endorsers and guarantors of, and sureties for,
this Note waive presentment for payment, demand, notice of dishonor, protest,
and notice of protest with regard to the Note, all errors, defects and
imperfections in any proceedings instituted by Payee under the terms of this
Note, and all

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benefits that might accrue to Maker by virtue of any present or future laws
exempting any property, real or personal, or any part of the proceeds arising
from any sale of any such property, from attachment, levy or sale under
execution, or providing for any stay of execution, exemption from civil process,
or extension of time for payment; and Maker agrees that any real estate that may
be levied upon pursuant to a judgment obtained by virtue hereof, on any writ of
execution issued hereon, may be sold upon any such writ in whole or in part in
any order desired by Payee.

      7. Unconditional Liability. Maker hereby waives all notices in connection
with the delivery, acceptance, performance, default, or enforcement of the
payment of this Note, and agrees that its liability shall be unconditional,
without regard to the liability of any other party, and shall not be affected in
any manner by any indulgence, extension of time, renewal, waiver or modification
granted or consented to by Payee, and consents to any and all extensions of
time, renewals, waivers, or modifications that may be granted by Payee with
respect to the payment or other provisions of this Note, and agrees that
additional makers, endorsers, guarantors, or sureties may become parties hereto
without notice to them or affecting their liability hereunder.

      8. Notices. Any notice called for hereunder shall be deemed properly given
if (i) sent by certified mail, return receipt requested, (ii) personally
delivered, (iii) dispatched by any form of private or governmental express mail
or delivery service providing receipted delivery, (iv) sent by telefacsimile or
(v) sent by e-mail, to the following addresses or to such other address as
either party may designate by notice in accordance with this Section:

      If to the Maker:
            Asia Automotive Acquisition Corporation
            401 South Old Woodward, Suite 450
            Birmingham, Michigan 48009
            Attn: David J. Brophy, Chief Financial Officer

      If to the Payee:

            William R. Herren
            4583 Dartmouth
            Saginaw, Michigan 48603

Notice shall be deemed given on the earlier of (i) actual receipt by the
receiving party, (ii) the date shown on a telefacsimile transmission
confirmation, (iii) the date on which an e-mail transmission was received by the
receiving party's on-line access provider (iv) the date reflected on a signed
delivery receipt, or (vi) two (2) Business Days following tender of delivery or
dispatch by express mail or delivery service.

      9. Construction. This Note shall be construed and enforced in accordance
with the domestic, internal law, but not the law of conflict of laws, of the
State of Michigan.

      10. Severability. Any provision contained in this Note which is prohibited
or unenforceable in any jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction shall not invalidate or render
unenforceable such provision in any other jurisdiction.

      IN WITNESS WHEREOF, Maker, intending to be legally bound hereby, has
caused this Note to be duly executed by its Chief Executive Officer the day and
year first above written.

                                      ASIA AUTOMOTIVE ACQUISITION CORPORATION

                                      By: /s/ David J. Brophy
                                          -------------------------
                                          Name: David J. Brophy
                                          Title: Chief Financial Officer

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