Special order – Usually takes 2-3 weeks – Click here for more information!
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What does the phrase 'Will be special ordered for you' entail?
This indicates that the product is not currently stocked in our warehouse. We procure 'Special Order' items directly from the supplier upon receiving your order. Typically, we do not maintain inventory for these items.
'Special Order' products may either be shipped directly from the supplier or routed through our facilities before reaching you. The available shipping options will be presented during the checkout process.
Once you place an order for a Special Order item, we will specially order it for you, and there is a restocking fee of up to 15% depending on the item in case of cancellations.
As Roco 4x4, we commit to providing updates on your order within a maximum of 2 business days, offering an estimated time of arrival (ETA) for the item. In the event that the item is discontinued, we will promptly notify you.
Cylinder Head Specifications:; Combustion chamber volume: 87cc; Intake runner volume: 215cc; Exhaust runner volume: 175cc; Intake valve diameter: 2.11"; Exhaust valve diameter: 1.66"; Valve stem diameter: 11/32"; Valve guides: Manganese bronze; Deck thickness: 5/8"; Valve spring diameter: 1.46"; Valve spring maximum lift: .575"; Rocker stud: 7/16"; Guideplate: Hardended steel; Pushrod diameter: 5/16"; Valve angle: 14°; Exhaust port location: Stock Ram Air IV; Spark plug fitment: 14mm x 3/4 reach, gasket seat. These cylinder heads are designed for outstanding performance gains in 1962-79 389-455 c.i.d. Pontiac engines. They are patterned after the 1969-70 Ram Air IV Pontiac cylinder head. Performer heads #60579/#60575 are 50-state emissions legal for 1965-79 vehicles. They feature 87cc combustion chambers designed to maximize performance while using less expensive, low-octane fuel with a streetable 9.5:1 compression ratio. Our Performer RPM heads with the 72cc combustion chamber are for higher compression engines. Performer RPM #60509 is semi-machined and must be finished by a professional cylinder head porter. They include valve guides and seats installed with no intake pushrod holes. Performer RPM #60587 is not port matched or bowl blended and is NHRA accepted for Stock & Super Stock. INSTALLATION NOTE: These heads require Ram Air IV (round port) style exhaust manifolds or headers and Edelbrock head bolt kit #8549. Deck thickness: 5/8", rocker stud diameter: 7/16", pushrod diameter: 5/16" (width of slot in guide plate).