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                                                                    EXHIBIT 10.8


                                    GUARANTY

         This Guaranty ("Guaranty") is entered into as of January 23, 2004 by
Paul A. Kruger, a resident of the State of Florida ("Guarantor"), for the
benefit of SXJE, LLC ("SXJE").

         WHEREAS, SXJE has required that Guarantor guaranty the payment of any
and all amounts owed by Boundless Motor Sports Racing, Inc., a Colorado
corporation (the "Company"), under that certain promissory note, of even date
herewith, in the original principal amount of $l,000,000, and with the Company
as "maker" and SXJE as "payee" (the "Note"); and

         WHEREAS, Guarantor will derive a specific benefit from SXJE providing
the loan to the Company pursuant to the Note, and desires to guarantee the
payment of any and all amounts owed by the Company under the Note (the
"Obligations");

         NOW, THEREFORE, for valuable consideration, the receipt and adequacy of
which are hereby acknowledged, Guarantor hereby guarantees to SXJE the payment
of all Obligations, on the following terms:

         1. Continuing Guaranty. Upon the occurrence of an Event of Default (as
defined in the Note), Guarantor hereby guarantees and promises to pay, on
written demand by SXJE, all of the unpaid Obligations. This Guaranty is given in
consideration for credit and other financial accommodations made by SXJE to the
Company.

         2. Waivers. Except as provided in Section 1 above, Guarantor hereby
waives:

                  (a) presentment for payment;

                  (b) notice of dishonor, demand, protest, and notice thereof as
to any instrument, and all other notices and demands to which Guarantor might be
entitled;

                  (c) any right to require the SXJE to institute suit against,
or to exhaust its rights and remedies against, the Company or any other person,
or to proceed against any property of any kind which secures all or any part of
the Obligations, or to exercise any right of offset or other right with respect
to any reserves, credits or deposit accounts held by or maintained with SXJE or
any indebtedness of SXJE to the Company, or to exercise any other right or
power, or pursue any other remedy SXJE may have;

                  (d) any defense based upon any failure of SXJE to give
Guarantor notice of any sale or other disposition of any property securing any
or all of the Obligations, or any defects in any such notice that may be given;

                  (e) any defense based upon or arising out of any bankruptcy,
insolvency, reorganization, arrangement, readjustment of debt, liquidation or
dissolution proceeding commenced by or against the Company or any other
guarantor or any endorser, co-maker or other person,

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including without limitation any discharge of, or bar against collecting, any of
the Obligations (including without limitation any interest thereon), in or as a
result of any such proceeding; and

                  (f) the benefit of any and all statutes of limitation with
respect to any action based upon, arising out of or related to this Guaranty.

If any claim is ever made upon SXJE for repayment or recovery of any amount or
amounts received by SXJE in payment of or on account of any of the Obligations,
because of any claim that any such payment constituted a preferential transfer
or fraudulent conveyance, or for any other reason whatsoever, and SXJE repays
all or part of said amount by reason of any judgment, decree or order of any
court or administrative body having jurisdiction over SXJE or any of its
property, or by reason of any settlement or compromise of any such claim
effected by SXJE with any such claimant (including, without limitation, the
Company), then and in any such event, Guarantor agrees that any such judgment,
decree, order, settlement and compromise shall be binding upon Guarantor,
notwithstanding any revocation or release of this Guaranty or the cancellation
of any note or other instrument evidencing any of the Obligations, or any
release of any of the Obligations, and Guarantor shall be and remain liable to
SXJE under this Guaranty for the amount so repaid or recovered, to the same
extent as if such amount had never originally been received by SXJE, and the
provisions of this sentence shall survive, and continue in effect,
notwithstanding any revocation or release of this Guaranty.

         3. Consents. Guarantor hereby consents and agrees that, without notice
to or by Guarantor and without affecting or impairing in any way the obligations
or liability of Guarantor hereunder, SXJE may, from time to time before or after
revocation of this Guaranty, do any one or more of the following in SXJE's sole
and absolute discretion: (a) accelerate, accept partial payments of, compromise
or settle, renew, extend the time for the payment, discharge, or performance of
refuse to enforce, and release all or any parties to, any or all of the
Obligations; (b) grant any other indulgence to the Company or any other person
in respect of any or all of the Obligations or any other matter; (c) accept,
release, waive, surrender, enforce, exchange, modify, impair, or extend the time
for the performance, discharge, or payment of, any and all property of any kind
securing any or all of the Obligations or any guaranty of any or all of the
Obligations, or on which SXJE at any time may have a lien, or refuse to
enforce its rights or make any compromise or settlement or agreement therefor in
respect of any or all of such property; (d) substitute or add, or take any
action or omit to take any action which results in the release of, any one or
more endorsers or guarantors of all or any part of the Obligations, including,
without limitation one or more parties to this Guaranty, regardless of any
destruction or impairment of any right of contribution or other right of
Guarantor, (e) amend, alter or change in any respect whatsoever any term or
provision relating to any or all of the Obligations, including the rate of
interest thereon; (f) apply any sums received from the Company, any other
guarantor, endorser, or co-signer, or from the disposition of any collateral or
security, to any indebtedness whatsoever owing from such person or secured by
such collateral or security, in such manner and order as SXJE determines in its
sole discretion, and regardless of whether such indebtedness is part of the
Obligation, is secured, or is due and payable; (g) apply any sums received from
Guarantor or from the disposition of any collateral or security securing the
obligations of Guarantor, to any of the Obligations in such manner and order
as SXJE determines in its sole discretion, regardless of whether or not such
Obligations is secured or is due and payable. Guarantor

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consents and agrees that SXJE shall be under no obligation to marshal any assets
in favor of Guarantor, or against or in payment of any or all of the
Obligations. Without limiting the generality of the foregoing, SXJE shall have
no obligation to monitor. verify, audit, examine, or obtain or maintain any
insurance with respect to, any property securing any or all of the Obligations.

         4. Representations and Warranties. Guarantor hereby represents and
warrants that (a) it is in Guarantor's direct interest to assist the Company in
procuring credit, because the Company is an affiliate of Guarantor and has a
direct business relationship with Guarantor, (b) this Guaranty has been duly and
validly authorized, executed and delivered and constitutes the valid and binding
obligation of Guarantor, enforceable in accordance with its terms, and (c) the
execution and delivery of this Guaranty does not violate or constitute a default
under (with or without the giving of notice, the passage of time, or both) any
order, judgment, decree, instrument or agreement to which Guarantor is a party
or by which it or its assets are affected or bound.

         5. Costs. Whether or not suit be instituted, Guarantor agrees to
reimburse SXJE on demand for all reasonable attorneys' fees and all other
reasonable costs and expenses incurred by SXJE in enforcing this Guaranty, or
arising out of or relating in any way to this Guaranty. In the event either SXJE
or Guarantor files any lawsuit against the other predicated on a breach of this
Guaranty, the prevailing party in such action shall be entitled to recover its
reasonable attorneys' fees and costs of suit from the non-prevailing party.

         6. Notices. Any notice which a party shall be required or shall desire
to give to the other hereunder shall be given by personal delivery or by
telecopier or by depositing the same in the United States mail, first class
postage pre-paid, addressed to SXJE at 2400 Bryon Circle, Lansing, Michigan
48912, Attn: Sam Eyde, and to Guarantor at 2500 McGee Drive, Suite 147, Norman,
Oklahoma 73072, and such notices shall be deemed duly given on the date of
personal delivery or one day after the date telecopied or 3 business days after
the date of mailing as aforesaid. SXJE and Guarantor may change their address
for purposes of receiving notices hereunder by giving written notice thereof to
the other party in accordance herewith Guarantor shall give SXJE immediate
written notice of any change in his address.

         7. Severability. If any provision of this Guaranty or the application
thereof to any party or circumstance is held invalid, void, inoperative or
unenforceable, the remainder of this Guaranty and the application of such
provision to other parties or circumstances shall not be affected thereby, the
provisions of this Guaranty being severable in any such instance.

         8. General Provisions. SXJE shall have the right to seek recourse
against Guarantor to the full extent provided for herein and in any other
instrument or agreement evidencing obligations of Guarantor to SXJE, and against
the Company to the full extent of the Obligations. No election in one form of
action or proceeding, or against any party, or on any obligation, shall
constitute a waiver of SXJE's right to proceed in any other form of action or
proceeding or against any other party. The failure of SXJE to enforce any of the
provisions of this Guaranty at any time or for any period of time shall not be
construed to be a waiver of any such provision or the right thereafter to
enforce the same. All remedies hereunder shall be cumulative and shall be in
addition to all rights, powers and remedies given to SXJE by law or under any
other instrument or agreement. Time is of the essence in the


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performance by Guarantor of each and every obligation under this Guaranty. This
Guaranty is the entire and only agreement between Guarantor and SXJE with
respect to the guaranty of the Obligations of the Company by Guarantor, and all
representations, warranties, agreements, or undertakings heretofore or
contemporaneously made, which are not set forth herein, are superseded hereby.
No course of dealings between the parties, no usage of the trade, and no parol
or extrinsic evidence of any nature shall be used or be relevant to supplement
or explain or modify any term or provision of this Guaranty. There are no
conditions to the full effectiveness of this Guaranty. The terms and provisions
hereof may not be waived, altered, modified, or amended except in a writing
executed by Guarantor and SXJE. All rights, benefits and privileges hereunder
shall inure to the benefit of and be enforceable by SXJE and its successors and
assigns and shall be binding upon Guarantor and his heirs, executors,
administrators, personal representatives, successors and assigns. Neither the
death of Guarantor nor notice thereof to SXJE shall terminate this Guaranty as
to his estate, and, notwithstanding the death of Guarantor or notice thereof to
SXJE, this Guaranty shall continue in full force and effect with respect to all
Obligations, including without limitation Obligations incurred or created after
the death of Guarantor and notice thereof to SXJE. Section headings are used
herein for convenience only. Guarantor acknowledges that the same may not
describe completely the subject matter of the applicable Section, and the same
shall not be used in any manner to construe, limit, define or interpret any term
or provision hereof.

         9. Choice of Law. THIS GUARANTY SHALL BE CONSTRUED IN ACCORDANCE WITH
THE INTERNAL LAWS OF THE STATE OF TEXAS, WITHOUT REGARD TO ITS CHOICE OF LAWS
PROVISIONS.

         IN WITNESS WHEREOF, Guarantor has executed this Guaranty as of the date
first above written.

                                                    /s/ Paul A. Kruger
                                                    ----------------------------
                                                    Paul A. Kruger




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