Dimensions: Click here for dimensions. A separate window will open. Please check for clearance issues with firewalls, brake bosters, alternator, air conditioning brackets, and the like.
Finishes: Read about finishes and construction of PML parts.
These tall, 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.
- Traditional CORVETTE script 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
- No brake booster indent
- 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
Chevrolet big block engines include: 396, 427, 454, and the 502
These valve covers are a bit taller than stock without oil drippers and no brake booster relief 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 covers with a brake booster relief, see PML regular, standard height valve covers with CORVETTE script and fins, PML Part Number 9096.
General Motors Trademarks are 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.
- 1930 Ford
- 1963 Corvette
- 1966 Corvette (625 HP)
- 1966 Corvette
- 1969 Corvette
- 1970 Monte Carlos
- 1973 Corvette
Mike purchased PML valve covers for his big block engine on his 1930 Ford Five Window Coupe street rod. This street rod does not have have a hood or fenders, similar to the American Graffiti Deuce Coupe. He chose the CORVETTE script in the cast finish to be "slightly different". Our thanks to Mike for sharing his pictures and his comments.
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 uses 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.
These images show a restoration by Alloway's Hot Rod Shop. The engine is dressed up with these PML tall big block CORVETTE valve covers in the polish finish.
1966 Corvette (625 HP)
David in Barrington, Illinois, installed these valve covers in the polish finish on his 1966 Corvette with a Chevy big block 625 HP engine. He emailed us "I love my valve covers!!"
1966 Corvette, PML valve covers on Chevy big block engine, image shows passenger side
1966 Corvette, PML valve covers on Chevy big block engine, image shows driver side
Click on image to view larger in a new tab or window.
Lou Cardoza Enterprises in Hawaii/Guam (808-238-1374) built this 427 engine for a 1966 Corvette and finished it off with PML tall big block valve covers in the polish finish.
This Corvette belongs to PML's owner and president. His 427 engine does not have roller rockers. He decided on these tall PML big block valve covers because he did not need the brake booster relief and liked the look. He custom painted red between the fins and script to match his Vette.
1970 Monte Carlo
John Engle built a roller cam 454 topped with an MSD throttle body elecronic fuel injection unit, an American Billet belt drive kit, Vintage Air conditioning unit, and a Tremec TKO 600 5 speed transmission.
John wanted the CORVETTE script to pop so he painted the background black using an Eastwood two-part epoxy paint.
Our thanks to John for sharing the details of his build and pictures.
1970 Monte Carlo 427 with a Big Block Engine
Passenger side of 1970 Monte Carlo big block engine
Driver side of 1970 Monte Carlos big block engine
Click on image to view larger in a new tab or window.
Video slide show (short) has pictures of these PML valve covers, polish finish, installed on Chuck Younger's 1973 Corvette with a Chevrolet big block engine. Chuck's company is Walden and Younger Corvette Restorations out of Alabama.
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.
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.
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).
Because these covers are larger than stock, on some Corvette engines, you may need to remove the alternator to install these covers. Accessing some of the bolts may be difficult.
These valve covers do NOT have a relief for the brake booster. See are regular, standard height valve covers if a relief or indent for the brake booster is needed.
Inside of Valve Covers
Always check your engine configuration for clearance requirements before ordering.
These valve covers feature an open interior for clearance for many roller rocker systems. There are no old drippers or brake booster relief for maximum internal height and space.
The baffle for the PCV and breather holes is part of the casting. There are not any screws or plates to come loose.
Click to view or print PML Big Block Valve Covers PDF Flyer. A separate window will open and load the pdf file.