Dimensions: Click here for dimensions.
Number of Bolts: 4 per stock cover, on the top, PML cover uses 2 bolt as PML cover is thick and rigid so 2 bolts is plenty for a no leak seal
Finishes: Read about finishes and construction of PML parts.
The valve covers feature vintage CHEVROLET lettering and fins for a classic appearance. PML made these for GM Generation II LT1 and LT4 small block engines, center bolt mounting.
- Traditional look
- Heavy duty sand cast aluminum construction for secure two bolt clamping on the cylinder head
- Optional PCV/Breather/Oil Fill holes on intake manifold side for a functional yet clean design
- Gasket and new mounting bolts included
- Slightly taller than stock
- CHEVROLET script used under license to PML, Inc., by General Motors
Award winning two–bolt design: These valve covers won the SEMA 2007 Global Media Award for the two bolt mounting design. Stock valve covers have four bolts holding the cover on to the engine. PML two bolt design removes the two center bolts for an attractive presentation.
Because PML valve covers have thick wall, sand cast aluminum construction, they are much stiffer than stock and need only two bolts to apply pressure evenly to the gasket. PML valve covers will not tweak, bend, twist or deform. No leaks and a great look to dress up your engine.
The CHEVROLET script and fins are cast into the cover and are raised. On powder coated parts, the powder coat is shaved off the top of the script and the fins.
Also available with CORVETTE script.
Gaskets: One set of custom cork composite gaskets included with each set of valve covers. For additional gaskets, see Gasket for Chevy Small Block Valve Covers, Center Bolt.
General Motors Trademarks are used under license to PML, Inc.
PML made these valve covers for GM Generation II LT1 and LT4 small block engines, center bolt mounting to the cylinder head.
These applications may have Chevy small block engines with center bolt mounting and be able to use these valve covers:
- Crate engines, such as ZZ4 and Ramjet
- 1987 to 1998 Silverado, Sierra, Suburban, Tahoe
- 1987 to 1998 Corvette, Impala SS, Camaro Z28
- Mid 90s Pontiac Camaro and Firebird
Configurations vary! Always check your engine before ordering. See SPECIFICATIONS for information on fitment and PCV/oil fill and breather holes.
These valve covers are larger than stock. On many stock engines, there is a bracket close to the stock covers that will need modifying to work with these PML covers.
1995 C1500 Truck
These PML Chevrolet valve covers on a 1995 C1500 Pickup made the cover of September 2010 Street Trucks Magazine. Read the whole article (pdf file). This article shows the natural as-cast finish valve covers.
The truck has a GM Performance Parts HT383 crate motor and a Weiand intake manifold. Read more about the truck on the Street Trucks website — search for "Operation Muscle Truck".
1966 Chevy II
Derrick installed these valve covers on his 1966 Chevy II 327 small block. He ordered the covers with a breather hole machined on the rear of the driver side cover and a PCV hole machined on the rear of the passenger side cover.
Danny was very pleased to receive these PML valve covers as a Christmas gift from his wife. He installed them on his 1955 Belair with a ZZ4 350 engine.
1955 Chevy Truck
PML small block center bolt valve covers on a 1955 Chevy Shortbed, step side, small window, with a GM ZZ4 motor.
Restoration done by and pictures courtesy of Schneider Racing Cams.
Jay restored this 1934 Chevy Street Rodder over the course of 10 months with some help from his friends. He installed PML's small block valve covers with Chevrolet script. He plans to paint the valve covers to match his wheels. This image shows the valve covers with the natural as-cast finish.
Our thanks to Jay for sharing his pictures.
9C1 Police Interceptor ZZ4 withe 385 Fast Burn Heads
Micah Sheveloff at www.micahsheveloff.com installed these PML small block Chevy valve covers on his 9C1 Police Interceptor. The engine is a GM Crate ZZ4 Engine with 385 Fast Burn Heads. Micah selected the black powder coat finish with PCV and breather holes, both towards the rear.
5.7 Vortec Engine
Joseph Mendez, Tech Editor for Lowrider Scene Magazine, beautifully engraved a small block Chevy 5.7L Vortec engine from a 1995 Silverado. The engine is topped with PML valve covers.
Street Trucks Magazine
For a great step-by-step installation article of these valve covers, see Street Trucks July 2009 magazine article "Retro Rocker Covers" (click at right for a pdf of the article). This article uses the valve covers with the black powder coat finish.
Read about our center bolt valve covers on corvetteforum.com.
Click here for dimensions. Use these dimensions to check if PML valve covers will fit on your engine.
PML fits each valve cover on an original GM cast iron cylinder head.
These valve covers may fit differently on aluminum or aftermarket heads. Keep this information in mind:
- PML covers are slightly larger than stock.
- The extra height allows for many types roller rockers but not all.
- Check for interference. Some engines have a bracket or other parts that sit close to the stock covers. Some customers have reported modifying their alternator bracket so these covers will fit.
PML Small Block Valve Covers with Rocker Arms
PML designed small block Chevy valve covers to work with many roller rocker systems. However, our valve covers are not compatible with shaft mounted rocker arms such as T&D.
The T&D Machine Products Competition Rocker Arms are shown in this image. The shaft mounts are very tall, almost to the top of the rocker arms. The PML cast-in internal baffles will contact these mounts.
Any rocker system must have space between the rocker arms for the baffle webbing inside the PML valve covers to fit between the arms.
Inside of PML Valve Covers and Baffles
Image shows inside of a valve cover. The areas next to the bolt holes are baffles for optional PCV and breathers. These are cast–in.
Optional PCV, Breather and Oil Fill Holes
Read this PDF file on oil fill, breather and PCV holes (click here).
PML small block valve covers are made without holes for PCV, oil fill or breather. PML can machine holes to your specifications.
For engines that require PCV and breather holes on the valve cover, PML designed the casting to be thicker on the intake manifold side and put baffles on the inside in two locations for holes. The top of the cover cannot be machined.
A separate oil fill hole is not needed since the PCV or push-in breather can be removed and oil added there.
PML uses four or five different tools on a CNC machine to create a clean, leak-free hole for PCV, breather or oil fill. Spot facing provides a smooth sealing surface for grommets.
To learn more, we have two videos.
The information is generally the same although a different PML valve cover is shown in these videos.
When ordering holes, you will need to specify the hole location. Holes can be machined on the passenger's side cover or on the driver's side cover, towards the front of the car or towards the rear. You can choose the location and type of hole needed in the shopping cart or can call to order. International customers, please email us for ordering.
Included With Valve Covers
PML includes new mounting bolts and a set of our custom cork composite gaskets with the valve covers.
PML includes a set of our thick, cork composite gaskets with our valve covers. Gaskets are approximately 0.25 inches thick. We designed these for easy installation and to provide a leak proof seal. For additional gaskets, see Gasket for Chevy Small Block Valve Covers, Center Bolt.
Depending on the engine configuration, using less thick gaskets or gaskets made from other materials may cause installation problems or not completely seal. For example, PML valve covers have a rail to hold the gasket in place while placing the valve cover and gasket on the cylinder head and if a thick gasket is not used, the rail may contact the cylinder head, preventing a good seal.
PML Valve Covers Compared to Stock
These images show a PML valve cover compared to the stock cover. The outside dimensions are shown. The distance to the gasket surface maybe different.