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                                                                  EXHIBIT 10.1.3

                                August 18, 2005

Asia Automotive Acquisition Corporation
401 South Old Woodward, Suite 450
Birmingham, Michigan 48009

Rodman & Renshaw, LLC
1270 Avenue of the Americas, 16th Floor
New York, NY 10020

            Re: Initial Public Offering

Gentlemen:

            The undersigned stockholder and director of Asia Automotive
Acquisition Corporation ("Company"), in consideration of Rodman & Renshaw, LLC
("Rodman & Renshaw") entering into a letter of intent ("Letter of Intent") to
underwrite an initial public offering of the securities of the Company ("IPO")
and embarking on the IPO process, hereby agrees as follows (certain capitalized
terms used herein are defined in paragraph 12 hereof):

            1. If the Company solicits approval of its stockholders of a
Business Combination, the undersigned will vote all Insider Shares owned by it
in accordance with the majority of the votes cast by the holders of the IPO
Shares.

            2. In the event that the Company fails to consummate a Business
Combination within 18 months from the effective date ("Effective Date") of the
registration statement relating to the IPO (or 24 months under the circumstances
described in the prospectus relating to the IPO), the undersigned will vote all
Insider Shares owned by it in favor of the Company's decision to liquidate. The
undersigned hereby waives any and all right, title, interest or claim of any
kind in or to any distribution of the Trust Fund (as defined in the Letter of
Intent) and any remaining net assets of the Company as a result of such
liquidation with respect to its Insider Shares ("Claim") and hereby waives any
Claim the undersigned may have in the future as a result of, or arising out of,
any contracts or agreements with the Company and will not seek recourse against
the Trust Fund for any reason whatsoever. In the event of the liquidation of the
Trust Fund, the undersigned agrees to indemnify and hold harmless the Company,
pro rata with the other officers and directors of the Company, based on the
number of Insider Shares held by each such individual, against any and all loss,
liability, claims, damage and expense whatsoever

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(including, but not limited to, any and all legal or other expenses reasonably
incurred in investigating, preparing or defending against any litigation,
whether pending or threatened, or any claim whatsoever) which the Company may
become subject as a result of any claim by any vendor or other person who is
owed money by the Company for services rendered or products sold or contracted
for, or by any target business, but only to the extent necessary to ensure that
such loss, liability, claim, damage or expense does not reduce the amount in the
Trust Fund. The foregoing sentence is not for the benefit of any third party
creditors of the Company.

            3. In order to minimize potential conflicts of interest which may
arise from multiple affiliations, the undersigned agrees to present to the
Company for its consideration, prior to presentation to any other person or
entity, any suitable opportunity to acquire an operating business, until the
earlier of the consummation by the Company of a Business Combination, the
liquidation of the Company or until such time as the undersigned ceases to be an
officer or director of the Company, subject to any pre-existing fiduciary and
contractual obligations the undersigned might have.

            4. The undersigned acknowledges and agrees that the Company will not
consummate any Business Combination which involves a company which is affiliated
with any of the Insiders unless the Company obtains an opinion from an
independent investment banking firm reasonably acceptable to Rodman & Renshaw
that the business combination is fair to the Company's stockholders from a
financial perspective.

            5. Neither the undersigned, any member of the family of the
undersigned, nor any affiliate ("Affiliate") of the undersigned will be entitled
to receive and will not accept any compensation for services rendered to the
Company prior to the consummation of the Business Combination. Notwithstanding
the foregoing to the contrary, the undersigned shall be entitled to
reimbursement from the Company for its out-of-pocket expenses incurred in
connection with seeking and consummating a Business Combination and commencing
on the Effective Date, Asia Development Capital LLC ("Related Party"), shall be
allowed to charge the Company $7,500 per month, representing an allocable share
of Related Party's overhead, to compensate it for the Company's use of Related
Party's offices, utilities and personnel.


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            6. Neither the undersigned, any member of the family of the
undersigned, nor any Affiliate of the undersigned will be entitled to receive or
accept a finder's fee or any other compensation in the event the undersigned,
any member of the family of the undersigned or any Affiliate of the undersigned
originates a Business Combination.

            7. The undersigned will escrow its Insider Shares for the three year
period commencing on the Effective Date subject to the terms of a Stock Escrow
Agreement which the Company will enter into with the undersigned and an escrow
agent acceptable to the Company.

            8. The undersigned agrees to be Chairman of the Board of the Company
until the earlier of the consummation by the Company of a Business Combination
or the liquidation of the Company. The undersigned's biographical information
furnished to the Company and Rodman & Renshaw and attached hereto as Exhibit A
is true and accurate in all respects, does not omit any material information
with respect to the undersigned's background and contains all of the information
required to be disclosed pursuant to Item 401 of Regulation S-K, promulgated
under the Securities Act of 1933. The undersigned's Questionnaire furnished to
the Company and Rodman & Renshaw and annexed as Exhibit B hereto is true and
accurate in all respects. The undersigned represents and warrants that:

      (g) he is not subject to or a respondent in any legal action for, any
injunction, cease-and-desist order or order or stipulation to desist or refrain
from any act or practice relating to the offering of securities in any
jurisdiction;

      (h) he has never been convicted of or pleaded guilty to any crime (i)
involving any fraud or (ii) relating to any financial transaction or handling of
funds of another person, or (iii) pertaining to any dealings in any securities
and he is not currently a defendant in any such criminal proceeding; and

      (i) he has never been suspended or expelled from membership in any
securities or commodities exchange or association or had a securities or
commodities license or registration denied, suspended or revoked.

            9. The undersigned has full right and power, without violating any
agreement by which he is bound, to enter into this letter agreement and to serve
as the Chairman of the Board of the Company.

            10. The undersigned authorizes any employer, financial institution,
or consumer credit reporting agency to release to Rodman & Renshaw and its legal
representatives

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or agents (including any investigative search firm retained by Rodman & Renshaw)
any information they may have about the undersigned's background and finances
("Information"). Neither Rodman & Renshaw nor its agents shall be violating the
undersigned's right of privacy in any manner in requesting and obtaining the
Information and the undersigned hereby releases them from liability for any
damage whatsoever in that connection.

            11. This letter agreement shall be governed by and construed and
enforced in accordance with the laws of the State of New York, without giving
effect to conflicts of law principles that would result in the application of
the substantive laws of another jurisdiction. The undersigned hereby (i) agrees
that any action, proceeding or claim against him arising out of or relating in
any way to this letter agreement (a "Proceeding") shall be brought and enforced
in the courts of the State of New York of the United States of America for the
Southern District of New York, and irrevocably submits to such jurisdiction,
which jurisdiction shall be exclusive, (ii) waives any objection to such
exclusive jurisdiction and that such courts represent an inconvenient forum and
(iii) irrevocably agrees to appoint Kramer Levin Naftalis & Frankel LLP as agent
for the service of process in the State of New York to receive, for the
undersigned and on his behalf, service of process in any Proceeding. If for any
reason such agent is unable to act as such, the undersigned will promptly notify
the Company and Rodman & Renshaw and appoint a substitute agent acceptable to
each of the Company and Rodman & Renshaw within 30 days and nothing in this
letter will affect the right of either party to serve process in any other
manner permitted by law.

            12. As used herein, (i) a "Business Combination" shall mean an
acquisition by merger, capital stock exchange, asset or stock acquisition,
reorganization or otherwise, of an operating business whose primary operations
are in India and selected by the Company; (ii) "Insiders" shall mean all
officers, directors and stockholders of the Company immediately prior to the
IPO; (iii) "Insider Shares" shall mean all of the shares of Common Stock of the
Company owned by an Insider prior to the IPO; and (iv) "IPO Shares" shall mean
the shares of Common Stock issued in the Company's IPO.

                                                     William R. Herren
                                                     ---------------------
                                                     Print Name of Insider

                                                 By: /s/ William R. Herren
                                                     ---------------------
                                                     Name: William R. Herren
                                                     Title: Chairman

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