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  <xs:element id="hlly_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationPeriodAfterFullyVested" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationPeriodAfterFullyVested" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="hlly_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsWeightedAverageFairValueAbstract" abstract="true" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsWeightedAverageFairValueAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="hlly_SupplementalCashFlowInformationRelatedToLeasesAbstract" abstract="true" name="SupplementalCashFlowInformationRelatedToLeasesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="hlly_DecapitalizationOfRightOfUseAssetsUponLeaseTerminationOrModification" abstract="false" name="DecapitalizationOfRightOfUseAssetsUponLeaseTerminationOrModification" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hlly_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hlly_DefinedContributionPlanEmployerDiscretionaryContributionPercentOfMatch" abstract="false" name="DefinedContributionPlanEmployerDiscretionaryContributionPercentOfMatch" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="hlly_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
