Exhibit 4.8


                         THIRD SUPPLEMENTAL INDENTURE


      THIRD SUPPLEMENTAL INDENTURE (this "Third Supplemental Indenture"), dated
as of December 31, 1999, among MOTORSPORTS BY MAIL, LLC, a North Carolina
limited liability company ("MBM"), SPEEDWAY FUNDING CORPORATION, a Nevada
corporation ("SFC") and collectively with MBM, the "Guaranteeing Subsidiaries"),
SPEEDWAY MOTORSPORTS, INC., a Delaware corporation (the "Company"), the other
guarantors listed on the signature pages to the Indenture and Supplemental
Indentures referred to below (the "Guarantors") and U.S. BANK TRUST NATIONAL
ASSOCIATION, as trustee under the Indenture referred to below (the "Trustee").

                                  WITNESSETH

      WHEREAS, the Company and the other Guarantors have heretofore executed and
delivered to the Trustee an Indenture dated as of August 4, 1997 (as
supplemented from time to time, the "Indenture"), providing for the issuance in
an aggregate principal amount of up to $200,000,000 of the Company's 8 1/2%
Senior Subordinated Notes due 2007 (the "Notes");

      WHEREAS, a First Supplemental Indenture dated as of April 1, 1999 (the
"First Supplemental Indenture") by and among the Company, the Guarantors, the
guaranteeing subsidiaries listed on the signature pages thereto and the Trustee
was previously entered into, supplementing the Indenture to add additional
Guarantors of the Notes;

      WHEREAS, a Second Supplemental Indenture dated as of June 1, 1999 (the
"Second Supplemental Indenture") by and among the Company, the Guarantors, the
guaranteeing subsidiaries listed on the signature pages thereto and the Trustee
was previously entered into, supplementing the Indenture to add additional
Guarantors of the Notes;

      WHEREAS, the parties hereto desire to execute and deliver this Third
Supplemental Indenture in order to amend the Indenture to add the Guaranteeing
Subsidiaries as Guarantors of the Notes in accordance with the Indenture;

      WHEREAS, the Indenture provides that under certain circumstances each of
the Guaranteeing Subsidiaries shall execute and deliver to the Trustee a
supplemental indenture pursuant to which each of the Guaranteeing Subsidiaries
shall unconditionally guarantee all of the Company's Obligations under the Notes
and the Indenture on the terms and conditions set forth herein (the "Note
Guarantee");

      WHEREAS, SFC is a wholly-owned subsidiary of the Company;

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      WHEREAS, MBM is a wholly-owned subsidiary of Speedway Systems, LLC, which
is an indirectly wholly-owned subsidiary of the Company;

      WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is
authorized to execute and deliver this Third Supplemental Indenture.

      NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, each of the
Guaranteeing Subsidiaries and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Notes as follows:

      1. Capitalized Terms. Capitalized terms used herein without definition
shall have the meanings assigned to them in the Indenture.

      2. Agreement to Guarantee. Each of the Guaranteeing Subsidiaries hereby
agrees as follows (notwithstanding anything to the contrary in this Third
Supplemental Indenture, such agreements of the Guaranteeing Subsidiaries shall
be construed as identical to those agreements made by the Guarantors under the
Indenture, and the obligations and rights of the Guaranteeing Subsidiaries
hereunder shall be no more and no less than those of the Guarantors under the
Indenture):

      (a) Along with all Guarantors named in the Indenture, to jointly and
severally unconditionally Guarantee to each Holder of a Note authenticated and
delivered by the Trustee and to the Trustee and its successors and assigns,
irrespective of the validity and enforceability of the Indenture, the Notes or
the obligations of the Company under this Third Supplemental Indenture, the
Indenture or the Notes, that:

            (i) the principal of and interest on the Notes will be promptly paid
      in full when due, whether at maturity, by acceleration, redemption or
      otherwise, and interest on the overdue principal of and interest on the
      Notes, if any, if lawful, and all other obligations of the Company to the
      Holders or the Trustee under this Third Supplemental Indenture, the
      Indenture or the Notes will be promptly paid in full or performed, all in
      accordance with the terms of this Third Supplemental Indenture, the
      Indenture and the Notes; and

            (ii) in case of any extension of time of payment or renewal of any
      Notes or any of such other obligations, that same will be promptly paid in
      full when due or performed in accordance with the terms of the extension
      or renewal, whether at stated maturity, by acceleration or otherwise.
      Failing payment when due of any amount so guaranteed or any performance so
      guaranteed for whatever reason, each of the Guaranteeing Subsidiaries and
      the Guarantors will be jointly and severally obligated to pay the same
      immediately.

      (b) The obligations of the Guaranteeing Subsidiaries hereunder and under
the Indenture shall be unconditional, irrespective of the validity, regularity
or enforceability of this Third

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Supplemental Indenture, the Notes or the Indenture, the absence of any action to
enforce the same, any waiver or consent by any Holder of the Notes with respect
to any provisions hereof, of the Indenture or of the Notes, the recovery of any
judgment against the Company, any action to enforce the same or any other
circumstance which might otherwise constitute a legal or equitable discharge or
defense of a guarantor.

      (c) The following is hereby waived by each of the Guaranteeing
Subsidiaries: diligence, presentment, demand of payment, filing of claims with a
court in the event of insolvency or bankruptcy of the Company, any right to
require a proceeding first against the Company, protest, notice and all demands
whatsoever.

      (d) This Note Guarantee shall not be discharged except by complete
performance of the obligations contained herein, and in the Notes and the
Indenture, and each of the Guaranteeing Subsidiaries accepts all obligations of
a Guarantor under the Indenture.

      (e) If any Holder or the Trustee is required by any court or otherwise to
return to the Company, the Guaranteeing Subsidiaries or the Guarantors, or any
Custodian, Trustee, liquidator or other similar official acting in relation to
either the Company, the Guaranteeing Subsidiaries or the Guarantors, any amount
paid by any of them to the Trustee or such Holder, this Note Guarantee, to the
extent theretofore discharged, shall be reinstated in full force and effect.

      (f) Each of the Guaranteeing Subsidiaries agrees that they shall not be
entitled to any right of subrogation in relation to the Holders in respect of
any obligations guaranteed hereby and by the Indenture until payment in full of
all obligations guaranteed hereby and by the Indenture.

      (g) As between the Guarantors and the Guaranteeing Subsidiaries, on the
one hand, and the Holders and the Trustee, on the other hand, (x) the maturity
of the obligations guaranteed hereby and by the Indenture may be accelerated as
provided in Article VI of the Indenture for the purposes of this Note Guarantee,
notwithstanding any stay, injunction or other prohibition preventing such
acceleration in respect of the obligations guaranteed hereby and by the
Indenture, and (y) in the event of any declaration of acceleration of such
obligations as provided in Article VI of the Indenture, such obligations
(whether or not due and payable) shall forthwith become due and payable by the
Guaranteeing Subsidiaries for the purpose of this Note Guarantee.

      (h) The Guaranteeing Subsidiaries and the Guarantors shall have the right
to seek contribution from any non-paying Guaranteeing Subsidiary or Guarantor so
long as the exercise of such right does not impair the rights of the Holders
under the Guarantee.

      (i) Notwithstanding anything to the contrary in this Third Supplemental
Indenture or in Article XI of the Indenture, the aggregate amount of the
Obligations guaranteed hereunder and under the Indenture by any Guaranteeing
Subsidiary shall be reduced to the extent necessary to prevent the Note
Guarantee of such Guaranteeing Subsidiary from violating or becoming voidable
under any law

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relating to fraudulent conveyance or fraudulent transfer or similar laws
affecting the rights of creditors.

      3. Execution and Delivery. Notwithstanding Section 11.02 of the Indenture,
each of the Guaranteeing Subsidiaries agrees that the Note Guarantees shall
remain in full force and effect notwithstanding any failure to endorse on each
Note a notation of such Note Guarantee.

      4.    Guaranteeing Subsidiaries May Consolidate Etc. on Certain Terms.
            ---------------------------------------------------------------

      (a) Except as set forth in Articles IV and V of the Indenture, nothing
contained in this Third Supplemental Indenture, in the Indenture or in any of
the Notes shall prevent any consolidation or merger of a Guaranteeing Subsidiary
with or into the Company or shall prevent any sale or conveyance of the property
of a Guaranteeing Subsidiary as an entirety or substantially as an entirety, to
the Company.

      (b) Except as set forth in Article IV of the Indenture, nothing contained
in this Third Supplemental Indenture, in the Indenture or in any of the Notes
shall prevent any consolidation or merger of a Guaranteeing Subsidiary with or
into a corporation or corporations other than the Company (whether or not
affiliated with the Guaranteeing Subsidiary), or successive consolidations or
mergers in which a Guaranteeing Subsidiary or its successor or successors shall
be a party or parties, or shall prevent any sale or conveyance of the property
of a Guaranteeing Subsidiary as an entirety or substantially as an entirety, to
a corporation other than the Company (whether or not affiliated with the
Guaranteeing Subsidiary) authorized to acquire and operate the same; provided,
however, that (i) each Guaranteeing Subsidiary hereby covenants and agrees that,
upon any such consolidation, merger, sale or conveyance, the Note Guarantee, and
the due and punctual performance and observance of all of the covenants and
conditions of this Third Supplemental Indenture and the Indenture to be
performed by such Guaranteeing Subsidiary, shall be expressly assumed (in the
event that the Guaranteeing Subsidiary is not the surviving corporation in the
merger) by supplemental indenture reasonably satisfactory in form to the
Trustee, executed and delivered to the Trustee, by the corporation formed by
such consolidation, or into which the Guaranteeing Subsidiary shall have been
merged, or by the corporation which shall have acquired such property and (ii)
immediately after giving effect to such transaction, no Default or Event of
Default would exist. In case of any such consolidation, merger, sale or
conveyance and upon the assumption by the successor corporation, by supplemental
indenture, executed and delivered to the Trustee and satisfactory in form to the
Trustee, of the Note Guarantee and the due and punctual performance of all of
the covenants and conditions of this Third Supplemental Indenture and the
Indenture to be performed by the Guaranteeing Subsidiary, such successor
corporation shall succeed to and be substituted for the Guaranteeing Subsidiary
with the same effect as if it had been named herein as a Guaranteeing
Subsidiary. Such successor corporation thereupon may cause to be signed any or
all of the Subsidiary Guarantees to be endorsed upon all of the Notes issuable
under the Indenture which theretofore shall not have been signed by the Company
and delivered to the Trustee. All the Subsidiary Guarantees so issued shall in
all respects have the same legal rank and benefit under the Indenture as the
Subsidiary Guarantees theretofore and thereafter issued in accordance with

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the terms of the Indenture as though all of such Subsidiary Guarantees had
been issued at the date of the execution of this Third Supplemental Indenture.

      5.    Releases.
            --------

      (a) Concurrently with any sale of assets (including, if applicable, all of
the capital stock of any Guaranteeing Subsidiary), any Liens in favor of the
Trustee in the assets sold thereby shall be released; provided, that in the
event of an Asset Sale, the Net Proceeds from such sale or other disposition are
treated in accordance with the provisions of Section 4.10 of the Indenture if
the assets sold in such sale or other disposition include all or substantially
all of the assets of any Guaranteeing Subsidiary or all of the capital stock of
any Guaranteeing Subsidiary, then such Guaranteeing Subsidiary (in the event of
a sale or other disposition or all of the capital stock of such Guaranteeing
Subsidiary) or the corporation acquiring the property (in the event of a sale or
other disposition of all or substantially all of the assets of a Guaranteeing
Subsidiary) shall be released and relieved of its obligations under its Note
Guarantee or Section 11.03 of the Indenture, as the case may be; provided, that
in the event of an Asset Sale, the Net Proceeds from such sale or other
disposition are treated in accordance with the provisions of Section 4.10 of the
Indenture. Upon delivery by the Company to the Trustee of an Officers'
Certificate and an Opinion of Counsel to the effect that such sale or other
disposition was made by the Company in accordance with the provisions of the
Indenture, including without limitation Section 4.10 of the Indenture, the
Trustee shall execute any documents reasonably required in order to evidence the
release of any Guaranteeing Subsidiary from its obligations under its Note
Guarantee.

      (b) Upon the release by all holders of Senior Indebtedness and Guarantor
Senior Indebtedness of all guarantees issued by a Guaranteeing Subsidiary
relating to such Senior Indebtedness and Guarantor Senior Indebtedness and all
Liens on the property and assets of such Guaranteeing Subsidiary relating to
Senior Indebtedness and Guarantor Senior Indebtedness, then such Guaranteeing
Subsidiary shall be released and relieved of any obligations under its Note
Guarantee. Upon delivery by the Company to the Trustee of an Officers'
Certificate and an Opinion of Counsel to the effect that all holders of Senior
Indebtedness and Guarantor Senior Indebtedness have released all guarantees
issued by a Guaranteeing Subsidiary and all Liens on the property and assets of
such Guaranteeing Subsidiary relating to such Senior Indebtedness and Guarantor
Senior Indebtedness, the Trustee shall execute any documents reasonably required
in order to evidence the release of such Guaranteeing Subsidiary from its
obligations under its Note Guarantee.

      (c) Any Guaranteeing Subsidiary not released from its obligations under
its Note Guarantee pursuant to either of paragraphs (a) or (b) of this Section 5
shall remain liable for the full amount of principal of and interest on the
Notes and for the other obligations of any Guarantor or any Guaranteeing
Subsidiary under this Third Supplemental Indenture or the Indenture,
respectively, as provided in Article XI of the Indenture or this Third
Supplemental Indenture, respectively.

      6. Subordination of Note Guarantees. The obligations of each Guaranteeing
Subsidiary under its Note Guarantee pursuant to this Third Supplemental
Indenture and Article XI of the


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Indenture shall be junior and subordinated to the Guarantor Senior Indebtedness
of such Guaranteeing Subsidiary on the same basis as the Notes are junior and
subordinated to Senior Indebtedness. For the purposes of the foregoing sentence,
the Trustee and the Holders shall have the right to receive and/or retain
payments by any of the Guaranteeing Subsidiaries only at such times as they may
receive and/or retain payments in respect of the Notes pursuant to the
Indenture, including Article X of the Indenture.

      7. No Recourse Against Others. No past, present or future director,
officer, employee, incorporator, stockholder or agent of either of the
Guaranteeing Subsidiaries, as such, shall have any liability for any obligations
of the Company, any Guarantor or any of the Guaranteeing Subsidiaries under the
Notes, the Subsidiary Guarantees, the Note Guarantees, the Indenture or this
Third Supplemental Indenture or for any claim based on, in respect of, or by
reason of, such obligations or their creation. Each Holder of the Notes by
accepting a Note waives and releases all such liability. The waiver and release
are part of the consideration for issuance of the Notes. Such waiver may not be
effective to waive liabilities under the federal securities laws and it is the
view of the SEC that such a waiver is against public policy.

      8. Second Supplemental Indenture. The Second Supplemental Indenture is
hereby amended and restated in its entirety by this Third Supplemental
Indenture.

      9. NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL
GOVERN AND BE USED TO CONSTRUE THIS THIRD SUPPLEMENTAL INDENTURE BUT WITHOUT
GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT
THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

      10. Counterparts. The parties may sign any number of copies of this Third
Supplemental Indenture. Each signed copy shall be an original, but all of them
together represent the same agreement.

      11. Effect of Headings. The Section headings herein are for convenience
only and shall not affect the construction hereof.

      12. The Trustee. The Trustee shall not be responsible in any manner
whatsoever for or in respect of the validity or sufficiency of this Third
Supplemental Indenture or for or in respect of the recitals contained herein,
all of which recitals are made solely by the Guaranteeing Subsidiaries and the
Company.



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      IN WITNESS WHEREOF, the parties hereto have caused this Third Supplemental
Indenture to be duly executed and attested, all as of the date first above
written.


                                       GUARANTEEING SUBSIDIARIES:
                                       -------------------------

                                       SPEEDWAY FUNDING CORPORATION

                                       By: /s/ William R. Brooks
                                           -------------------------
                                               Name:  William R. Brooks
                                               Title: Vice President

                                       MOTORSPORTS BY MAIL, LLC

                                       By: /s/ William R. Brooks
                                          -------------------------
                                               Name: William R. Brooks
                                               Title: Manager

                                       COMPANY:
                                       --------

                                       SPEEDWAY MOTORSPORTS, INC.

                                       By: /s/ William R. Brooks
                                          -------------------------
                                               Name:  William R. Brooks
                                               Title: Vice President

                                       GUARANTORS:
                                       -----------

                                       ATLANTA MOTOR SPEEDWAY, INC.

                                       BRISTOL MOTOR SPEEDWAY, INC.

                                       CHARLOTTE MOTOR SPEEDWAY, INC.

                                       SPR ACQUISITION CORPORATION

                                       TEXAS MOTOR SPEEDWAY, INC.



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                        600 RACING, INC.

                        SPEEDWAY CONSULTING & DESIGN, INC.

                        INEX CORP.

                        By: /s/ William R. Brooks
                           -------------------------
                           Name:  William R. Brooks
                           Title: Vice President
                        IMS SYSTEMS LIMITED PARTNERSHIP

                        By:   Speedway Motorsports, Inc., its general partner

                        By: /s/ William R. Brooks
                            -------------------------
                            Name:  William R. Brooks
                            Title: Vice President

                        LAS VEGAS MOTOR SPEEDWAY, LLC

                        SMI SYSTEMS, LLC

                        By: /s/ William R. Brooks
                            -------------------------
                            Name:  William R. Brooks
                            Title: Manager

                        SPEEDWAY STSTEMS, LLC

                        By: IMS Systems Limited Partnership, its sole manager

                             By: Speedway Motorsports, Inc., its general partner

                                By: /s/ William R. Brooks
                                    -------------------------
                                    Name:  William R. Brooks
                                       Title: Vice President


                                      8

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                                       TRUSTEE:
                                       --------


                                       U. S. BANK TRUST NATIONAL ASSOCIATION,
                                             as Trustee.

                                       By: /s/ Rick Prokosch
                                         --------------------------------
                                               Authorized Signatory


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