My Cart: 0 item(s)
Dimensions:
Click here for dimensions.
Check for clearance to firewalls, brake bosters, alternator, air conditioning brackets, and the like.
Number of Bolts: 7 per cover, on the perimeter
Finishes: Read about finishes and construction of PML parts.
These tall, heavy duty valve covers from PML for big block Chevy engines feature raised CHEVROLET script and fins and top quality construction. The classic CHEVROLET script is licensed from General Motors.
Benefits:
- Traditional design and sand cast aluminum construction for an old-school look and feel
- Taller than standard height and open interior to work with many roller rockers
- 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
- GM licensed product
Chevrolet big block engines include: 396, 427, 454, and the 502
These valve covers are a bit taller than stock to fit over many roller rockers. Always verify clearance before ordering. Using double gaskets to add height frequently causes leaks. Customers have reported to us that PML tall valve covers eliminated the need for double gaskets and the leaks.
For our standard height Chevy big block valve covers, see PML Part Number 9737.
Licensed GM product. All related Emblems and vehicle body designs are tradmarks of General Motors LLC, used under license to PML, Inc.
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 taller than stock so check for space for larger valve covers.
If using updated Camshaft or roller rockers, some modification may be needed. For example, Mike let us know that his 502 with aftermarket roller rockers and a 283 grind Thumpr from Comp Cams required that he grind a bit on the roller rockers so the valve covers would fit. The roller rockers are a generic kind, gold in color and very squared off. He used a standard gaskets, not extra thick. To get the PML covers to fit, he rounded off the left side corners on two of the roller rockers. The valve covers fit great after grinding a bit off the roller rockers on #1 intake and #6 intake (one intake rocker on each side of engine). He did not remove any material from the valve covers. He was told later by an engine machinist that this procedure is virtually always necessary when you try to put roller rockers on a big block chevy.
Loaner Program
We want to make sure you get valve covers that will work on your engine and you love looking at. With that in mind we have a program for borrowing a PML valve cover to test fit on an engine. Learn more about the PML Loaner Program.
Our thanks to our customers who have shared pictures of their installations.
Super Chevy Magazine chose these tall height PML Big Block Valve Covers for their 1967 Chevelle build. See their on-line article: Roller vs. Flat Tappet Cams
- 1955 Bel Air
- 1955 Chevrolet Bel Air with 454
- 1955 Chevrolet with 520 Engine
- 1955 Chevy 210 Sedan
- 1957 Bel Air
- 1965 Impala
- 1966 Chevelle
- 1970 Chevelle Ss
- 1972 Chevy Truck
- Miss Merion Bluegrass Hydroplane
- 502 Engine
- 502 Engine with Thumpr Comp Cam
1955 Bel Air
Tim Ruddick of Texas installed PML tall big block Chevy valve covers on his 1955 Bel Air with a 454 engine.
He emailed us to let us know that the covers fit perfectly and he had at least an inch of firewall clearance. He also said "I think they look awesome and went well with the old school theme in my engine compartment. The quality, fit and finish were first rate." Thank you Tim for sharing your pictures and letting us know.
Click on images to view larger.
1955 Chevrolet Bel Air with 454 Engine
Jay installed these valve covers on his 1955 Chevy Bel Air with a 454.
1955 Bel Air
1955 Bel Air with a 454 motor
Passenger side view of PML valve covers on the 454
454 engine, PML covers installed
Click on image to view larger in a new tab or window.
1955 Chevrolet with 540 Engine
John installed PML's tall big block valve covers on his 1955 Chevrolet with a 540 cu in engine. The covers have the polish finish. John also installed a PML transmission pan on his Chevy.
1955 Chevy 210 Sedan
We saw Shawn Fetter's beautiful 210 Sedan at the Grand National Roadster Show in January 2018. It won the Outstanding Overall Award in the Competiton Vehicle class. We'd like to think our valve covers had something to do with that!
Click on an image to view larger image in a new tab or window.
1957 Bel Air
Lance dressed up his 1957 Bel Air 496 big block with these PML valve covers. The engine features Pro Comp heads, roller cam and rockers, and .621 valve lift with 1.72 rocker arms. The engine is moved forward 1.75 inch.
1957 Bel Air, 496 Big Block
Pro Comp .621 valve lift with 1.72 rocker arms
PML valve cover on passenger side of 496 engine
PML valve cover on driver side of engine, 1957 Bel Air, 496 Chevy Big Block
Click on image to view larger in a new tab or window.
1965 Impala
Richard just finished his 1965 Impala SS with a 496 stroker when he sent us these pictures. His email noted that the engine got several compliments at the Impala's first car show.
1965 Impala SS
Stock valve covers on the Impala
Driver side of the 1965 Impala SS 496 stroker engine, PML valve covers installed
PML valve covers installed, passenger side view,
1965 Impala SS
Click on image to view larger in a new tab or window.
1966 Chevelle
Robert installed these PML big block valve covers in polish finish on his 1966 Chevrolet Chevelle with a 502 big block motor.
1966 Chevelle
original 502 motor valve covers
PML valve covers in polish finish
Click on image to view larger in a new tab or window.
1970 Chevelle SS
Billy installed these valve covers on his 1970 Chevy Chevelle SS with a 396 big block. He also purchase PML gaskets to go with the valve covers. The cast finish covers look great with the orange engine block and cast intake manifold.
Click on image to view larger.
1972 Chevy Truck
Jeff chose PML tall height big block valve covers in the orange powder coat finish for his 1972 Chevy pick up truck.
He purchased RM Specialties wire looms and oval shaped the holes with a dremel tool. The fit around the hole on the PML valve covers was too tight for the wire looms to work without modification. PML does not recommend grinding on the valve covers. Removing material from wire looms to fit the valve covers is usually a better option.
Click on an image to view larger.
Vintage Hydroplane, Miss Merion Bluegrass
Kirk installed PML valve covers on his Vintage Hydroplane, Miss Merion Bluegrass. Miss Merion Bluegrass has a 427 engine, Hilborn fuel injection and Dart Heads.
Click on image to view larger in a new tab or window.
502 Engine
Click on image to view larger.
PML polish finish valve covers installed on a Chevy 502 engine.
Thank you to our customer Jeff for providing the picture.
283 Grind Thumpr Comp Cams
Mike purchased PML valve covers for his big block engine on his 1930 Ford Coupe street rod. He also upgraded his Cam and roller rockers. His cam is a 283 grind Thumpr from Comp Cams and the roller rockers are a generic kind, gold in color and very squared off. He used a standard gaskets, not extra thick.
To get the PML covers to fit, he rounded off the left side corners on two of the roller rockers. The valve covers fit great after grinding a bit off the roller rockers on #1 intake and #6 intake (one intake rocker on each side of engine). He did not remove any material from the valve covers. He was told later by an engine machinist that this procedure is virtually always necessary when you try to put roller rockers on a big block chevy.
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.
The grommet for the breather is for any a breather cap with a 1 inch outer diameter tube.
Close up view showing that the PML Big Block Chevy valve cover has a
good fit with grommet and chrome push-in breather cap installed
PML Big Block Chevy valve cover, breather grommet, and chrome breather cap
PML Big Block Chevy valve cover, breather grommet and chrome
breather cap installed, top view
Click on small image to view larger image in a new tab or window.
Oil Fill
Either the PCV or breather hole can be used for oil fill. A separate oil fill hole and cap is not needed.
To add oil, PML suggests this procedure:
- Remove the PCV valve
- Remove the PCV grommet
- Put the PCV grommet on a funnel
- Cut off the end of the funnel so the bottom of the funnel is at the bottom of the PCV grommet
- Put the PCV grommet back in the valve cover
- Put the funnel the PCV grommet
- Add oil
- Remove funnel and put in PCV valve
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. This cover is approximately 3/8 to 1/2 inch taller than the stock cover. PML tall covers are approximately 3/8 inch taller than our standard height covers.
Some customers have reported that their roller rockers contact the inside of these PML valve covers at corners. PML has heard that grinding a bit off the roller rockers on #1 intake and #6 intake, one intake rocker on each side of engine, can add enough clearance (but this is not something we have tried or endorse).
Inside of Valve Covers
These valve covers have an open interior without oil drippers so that there is clearance for many roller rocker systems.
The baffle is cast into the covers. (It is the square feature between the bolt holes.)
Click on image to view larger in a new tab or window.
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
Click on image to view larger in a new tab or window.
