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Vehicle Info NeededHOLLEYPART NUMBER: 510-300-66
300-66 Pro-Jection 2-Barrel Manifold 1987-Up With Cast Iron Cylinder Heads
$54995
Ships on Sep 04, 2026
Lowest Price GuaranteePro-Jection EFI Intake Manifolds
- Pro-Jection 2-Barrel Manifold
- 1987-Up With Cast Iron Cylinder Heads
Features:
- Designed for use with Holley 2-bbl Pro-Jection throttle bodies.
- High rise/dual plane design.
- Idle-6000 RPM power band.
- EGR provision.
Installation Notes: Utilizes late model alternator and A/C bracket mounting provisions. Has vacuum taps off manifold runners. Extra installation hardware included.
Emissions Note:
This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.
CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART
RPM Range: Idle to 6,000
Designed for use with 2-barrel Pro-Jection throttle bodies, these manifolds utilize a high rise/dual plane design.
Features:
- Exhaust Heat Cross-Over
- EGR Provision
- Late Model Alternator & A/C Mounts
Note: These manifolds are NOT intended as an O.E. replacement for 1987-later fuel injected trucks.
Part TypeIntake Manifold
Product LineHolley Pro-Jection Intake Manifolds For Small Block Chevy
BrandHOLLEY
Package Height7.2
Package Width13.0
Package Length22.8
Weight19.94 PG
Part CategoryPerformance Parts
Runners RemovableNo
Number Of CarbsTwo
Supplemental Bosses Cast-InNo
Plenum MaterialAluminum
EmissionWithout EGR
Engine Make/SizeChevy Small Block
Basic Operating Rpm RangeIdle-6,000
Base FinishNatural
Rpm RangeIdle-6000
Injection StyleThrottle body
Base MaterialAluminum
Plenum FinishNatural
Aftermarket Fuel Rail RequiredNo
Engine Block StyleStock/OEM standard deck
UsageStreet/Strip
Throttle Body IncludedNo
PositionUpper
QuantitySold individually
Cylinder Head TypeStandard
Injectors IncludedNo
Fuel Rails IncludedNo
Intake Section IncludedComplete
EgrYes
Supplemental Bosses MachinedNo
Runners IncludedNo
Part FitmentSemi Universal
Vendor Part Number300-66
Package Qty1
Package TypeEA
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