PML designed these valve covers using original GM cast iron heads. Chevrolet Big block engines include: 396, 427, 454, and the 502.
These valve covers are standard height on the inside but taller than stock on the outside because of the thick walls and script and fins on top.
Engine configurations so check clearances.
Dimensions: Click here for a pdf file with dimensions. A separate window or tab will open.
Finishes: Read about finishes and construction of PML parts.
These heavy duty valve covers from PML for big block Chevy engines feature raised CORVETTE script and fins and top quality construction. The classic CORVETTE script is licensed from General Motors.
Benefits:
- Traditional design
- PCV and oil fill/breather holes
- Holes have internal baffles cast to reduce oil blow-by
- Thick walls and gasket flanges for strength and a secure seal to the cylinder head
- Sand cast construction for an old-school look and feel
Chevrolet big block engines include: 396, 427, 454, and the 502
PML also makes a tall height cover with out the brake booster indentation.
Gaskets
Gaskets are not included with these valve covers. PML designed these Chevy Big Block valve covers to work with cork composite gaskets.
Breather and PCV Holes
PML Chevy big block valve covers have PCV and oil fill/breather holes and baffles cast into the covers. The internal baffles help prevent oil blow-by out the PCV and breather holes.
These holes work with standard 1 1/4 inch grommets.
If desired, a breather cap with a 1 inch outer diameter tube can be used with the breather grommet.
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Checking Clearance
Click for dimension. A separate window or tab will open.
Engine configurations vary so please check for clearance for larger valve covers. The walls and gasket flange are thicker than stock and the fins and script add height to the top.
Look for clearance on the inside also, especially if you have roller rockers. A simple check can be made if you have the stock valve cover. Set the stock cover on the head and measure the distance, if any, between the gasket flange surface and the head.
The PML tall version of these valve covers is approximately 3/8 inch taller.
Brake Booster Relief
These valve covers feature a relief on the driver's side cover for the power brake booster. Our tall valve covers, PML Part Number 11042 do not have the relief.
PML used the recess from the 1969 Big Block 427 Corvette engine for the shape. Other years may have a slightly different recess.
These images show the brake booster relief cutout on a 1967 Corvette stock cover and the same area on a PML Corvette valve cover.
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Flyer
Click to view or print PML Big Block Valve Covers PDF Flyer. A separate window will open and load the pdf file.
PML Valve Covers Compared to Stock
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