The Holley GM LS1/LS2/LS6 Modular Hi-Ram Intake Manifold in black ceramic coating is a cost-effective alternative to fabricated sheet metal for high-performance induction where hood clearance isn't limited. Paired with the high-flowing LS1/LS2/LS6 cathedral port cylinder heads, it has strong potential in naturally aspirated and forced-induction combinations from 6.0 to 7.0+ liters, with peak power around 7,000-8,000+ RPM.
Specifications:
- Basic Operating RPM Range: 3500-8000
- Engine Application: GM LS1/LS2/LS6
- Manifold Type: Hi-Ram
- Flange Style: EFI
- Throttle Body Bore Diameter: 105mm
- Plenum Finish: Black
- Total Height (w/105mm EFI Top): 12.32\"
- Runner Length: 6.58\"
- Throttle Body Gasket Included: Yes
- Vacuum Ports: Yes
- Warranty: Manufacturer's Limited 90 Day Warranty
- Part Number: 300-123BK
EFI fuel rails are machined for -8AN O-ring fittings and come standard on EFI Hi-Ram kits. Designed to accept Bosch-style EV-1 or Magneti Marelli Pico injectors — stock LS fuel injectors may not fit properly.
Compliance: This part is legal for sale and use on Racing Use Only Vehicles — competition vehicles that are not registered and never operated on the street. It is against the law to install this part on an Emissions Controlled Vehicle (1966-and-newer California-certified or 1968-and-newer federally certified vehicles).
FAQ
What finish does the 300-123BK come in?
It's finished in black ceramic coating.
What throttle body size does this manifold use?
It comes with a 105mm EFI plenum top sized for a 105mm throttle body.
What's the power band on this Hi-Ram manifold?
It's built for 3,500-8,000 RPM, with peak output around 7,000-8,000+ RPM.
Is this manifold legal for street use?
No — it's Racing Use Only and cannot legally be installed on an emissions-controlled street vehicle.
