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                                                                EXHIBIT 10.16(b)

                              REVOLVING CREDIT NOTE

$12,307,720.00                                                New York, New York
                                                                October 24, 2003

         FOR VALUE RECEIVED, the undersigned, STANADYNE CORPORATION, a
corporation organized under the laws of the State of Delaware ("Stanadyne") and
PRECISION ENGINE PRODUCTS CORP., a corporation organized under the laws of the
State of Delaware ("Precision"; and together with Stanadyne, each individually,
a "Debtor" and collectively, the "Debtors"), HEREBY PROMISE TO PAY, jointly and
severally, to the order of GMAC COMMERCIAL FINANCE LLC, a Delaware limited
liability company ("Payee"), at the offices of GMAC COMMERCIAL FINANCE LLC, as
agent, at 461 Fifth Avenue, 21st Floor, New York, New York 10017, or at such
other place in the United States of America as Agent may from time to time
designate, the principal sum equal to the lesser of (a) TWELVE MILLION THREE
HUNDRED SEVEN THOUSAND SEVEN HUNDRED TWENTY DOLLARS ($12,307,720.00) or (b) the
aggregate unpaid principal amount of all Advances (each as defined in the Loan
Agreement referred to below) made by Payee to Debtor, which amount shall be
payable by Debtor in lawful money of the United States of America and in
immediately available funds in accordance with the terms of the Loan Agreement.
Debtors hereby further promise to pay, jointly and severally, interest to the
order of Payee on the unpaid principal balance hereof at the rates and in the
manner and in accordance with the terms and provisions of the Loan Agreement,
which terms and provisions are hereby incorporated herein by reference.

         For the purposes hereof, "Loan Agreement" shall mean that certain Loan
and Security Agreement dated of even date herewith, by and among GMAC Commercial
Finance LLC, as collateral agent and administrative agent ("Agent") for itself
and the lenders from time to time party thereto ("Lenders"), Debtors and
Stanadyne Automotive Holding Corp., as the same now exists or may hereafter be
amended, restated, renewed, replaced, substituted, supplemented, extended, or
otherwise modified. All capitalized terms used herein and not otherwise defined
herein shall have the meanings ascribed to such terms in the Loan Agreement.

         This Note evidences the aggregate outstanding principal balance, from
time to time, of the Revolving Advances made by Payee to each Debtor pursuant to
the Loan Agreement, the aggregate principal amount of which at any one time
outstanding Payee intends not to exceed, with respect to each Debtor, the
greater of (a) applicable Debtor's Individual Maximum Revolving Advance Amount
and (b) the applicable Debtor's Individual Formula Amount. It is contemplated
that there may be times when no indebtedness is owing hereunder; but
notwithstanding any such occurrence or occurrences, this Note shall remain valid
and shall be in full force and effect as to the Revolving Advances made
subsequent to each such occurrence.

         This Note is secured by the Collateral and is entitled to all of the
benefits and rights as set forth in the Loan Agreement and the Other Documents.
At the time any payment is due hereunder, at its option, Agent may charge the
amount thereof to any account of any Debtor maintained by Agent.

         If any Event of Default shall occur for any reason, or if the Loan
Agreement shall be terminated for any reason whatsoever, then and in any such
event, in addition to all rights and remedies of Agent and Payee under the Loan
Agreement and the Other Documents, applicable law or otherwise, all such rights
and remedies being cumulative, not exclusive and enforceable alternatively,
successively and

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concurrently, any or all of the Obligations, including, without limitation, all
amounts owing under this Note, may, as provided in the Loan Agreement, be
declared or shall forthwith become due and payable, together with all interest
accrued thereon and with interest accruing thereafter at the then applicable
interest rate under the Loan Agreement until the indebtedness evidenced by this
Note is paid in full, plus the costs and expenses of collection hereof,
including, but not limited to, reasonable attorneys' fees and legal expenses.

         Debtors hereby (i) waive diligence, demand, presentment, protest and
notice of any kind, (ii) agree that it will not be necessary to first institute
suit in order to enforce payment of this Note and (iii) consent to any one or
more extensions or postponements of time of payment, release, surrender or
substitution of collateral security, or forbearance or other indulgence, without
notice or consent. The pleading of any statute of limitations as a defense to
any demand against Debtors is expressly hereby waived by Debtors. Upon or after
maturity of this Note, or any Event of Default or termination of the Loan
Agreement, Payee, shall have the right, subject to the terms of the Loan
Agreement, but not the obligation, to set off against this Note all money owed
by Payee to Debtors.

         No resort to any Collateral for payment shall be required prior to the
enforcement hereof against Debtors and any guarantors or endorsers hereof. None
of the rights of Payee or Agent shall be waived or diminished by any failure or
delay in the exercise thereof.

         In the event any term or provision of this Note conflicts with any term
or provision of the Loan Agreement, such term or provision of the Loan Agreement
shall control.

         This Note shall be binding upon the respective successors and assigns
of Debtors and, subject to the terms of the Loan Agreement, shall inure to the
benefit of payee and its successors, endorsees and assigns. Whenever used
herein, the term "Debtors" shall be deemed to include each of the undersigned
and their respective successors and assigns and the terms "Payee" and "Agent"
shall be deemed to include their respective successors, endorsees and assigns.

         If any term or provision of this Note shall be held invalid, illegal or
unenforceable, the validity of all other terms and provisions hereof shall in no
way be affected thereby.

         This Note shall be governed by and construed in accordance with the
laws of the State of New York applied to contracts to be performed wholly within
the State of New York. Any judicial proceeding brought by or against Debtors
with respect to any of the Obligations, this Note or any related agreement may
be brought in any court of competent jurisdiction in the State of New York,
United States of America, and, by execution and delivery of this Note, each
Debtor accepts for itself and in connection with its properties, generally and
unconditionally, the non-exclusive jurisdiction of the aforesaid courts, and
irrevocably agrees to be bound by any final judgment rendered thereby in
connection with this Note. each Debtor hereby waives personal service of any and
all process upon it and consents that all such service of process may be made by
registered mail (return receipt requested) directed to such Debtor, and service
so made shall be deemed completed five (5) days after the same shall have been
so deposited in the mails of the United States of America. Nothing herein shall
affect the right to serve process in any manner permitted by law or shall limit
the right of Payee and/or Agent to bring proceedings against any Debtor in the
courts of any other jurisdiction. Each Debtor waives any objection to
jurisdiction and venue of any action instituted hereunder and shall not assert
any defense based on lack of jurisdiction or venue or based upon forum non
conveniens. Any judicial proceeding by any Debtor against Payee and/or Agent
involving, directly or indirectly, any matter or claim in any way arising out
of, related to or connected with this Note or any related agreement, shall be
brought only in a federal or state court located in the City of New York, State
of New York.

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EACH DEBTOR HEREBY EXPRESSLY WAIVES ANY RIGHT TO TRIAL BY JURY OF ANY CLAIM,
DEMAND, ACTION OR CAUSE OF ACTION ARISING UNDER THIS NOTE OR ANY OTHER
INSTRUMENT, DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH,
OR IN ANY WAY CONNECTED WITH OR RELATED OR INCIDENTAL TO THE DEALINGS OF SUCH
DEBTOR AND PAYEE AND/OR AGENT OR ANY OF THEM WITH RESPECT TO THIS NOTE OR ANY
OTHER INSTRUMENT, DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION
HEREWITH, OR THE TRANSACTIONS RELATED HERETO OR THERETO IN EACH CASE WHETHER NOW
EXISTING OR HEREAFTER ARISING, AND WHETHER SOUNDING IN CONTRACT OR TORT OR
OTHERWISE, AND EACH DEBTOR HEREBY CONSENTS THAT ANY SUCH CLAIM, DEMAND, ACTION
OR CAUSE OF ACTION SHALL BE DECIDED BY COURT TRIAL WITHOUT A JURY, AND THAT SUCH
DEBTOR, PAYEE AND/OR AGENT MAY FILE AN ORIGINAL COUNTERPART OR A COPY OF THIS
PARAGRAPH WITH ANY COURT AS WRITTEN EVIDENCE OF THE CONSENTS OF THE PARTIES
HERETO TO THE WAIVER OF THEIR RIGHT TO TRIAL BY JURY.

                                 STANADYNE CORPORATION

                                 By:    \s\ Stephen S. Langin
                                        ----------------------------------------
                                 Name:  Stephen S. Langin
                                 Title: Vice President & Chief Financial Officer

                                 PRECISION ENGINE PRODUCTS CORP.

                                 By:    \s\ Stephen S. Langin
                                        ----------------------------------------
                                 Name:  Stephen S. Langin
                                 Title: Vice President & Chief Financial Officer

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