TCKT B8

I pulled this valve cover off my 65 327. It has a casting line on it that goes vertically through the O in Corvette. Both covers have this line. Is this original or is it a aftermarket valve cover?

jimh_1962

Original 1966 later.

Nowhere Man

jet-tech

I believe the word "LESTER" will be on the inside of original valve covers. Like these covers I purchased from another member last week. Someone please correct me if I'm wrong. And sorry about the large size.

63 340HP

Was 1966 when the mold crack line appeared, or when the mold crack became so bad that the "o" started filling in?

Nowhere Man

Brian Kotula

My March4th 1966 build doesn't have the casting flaw, but like Nowhere Man said it happened sometime in 1966.

JLSmith

My April 19th built '66 does not have the flaw.
- Jeff

Powershift

There is really no "reproduction" of this valve cover. When GM stopped making them, they sold the mold to Paragon. Paragon continued to produce the valve cover using the original mold(s). So all would have the vertical crack and the word LESTER. Paragon continues to produce them to this day, but quality is poor due to age/condition of the original mold(s).

Larry

63 340HP

Is the flaw the faint crack line, or the debris closing part of the "o"?

68hemi

As others have stated correct for some time in 1966. They are NOT correct for your 1965 and the aluminum covers are only correct for 350 h.p. or higher h.p. in 1965.

Kerrmudgeon

No way to tell the original, later GM, or original Paragon covers from the originals.

6T7L71CPE

My covers have an offset PR next to the LESTER. I read these are Paragon made covers.

GUSTO14

One of the first purchases I made for my '63 327/250hp Corvette in 1969, was a set of the Corvette valve covers from my local Chevrolet dealer. $11 a piece , and they not only cured the leaking oil problem of the original tin covers, they added 25 more hp... according to my buddies.

The covers had the flaw in them which consisted of the casting line from the crack in the mold, but the "o" in Corvette was fully open as in the earlier covers. With a little work the casting flaw could be smoothed over and became invisible or nearly so.

Over the years, the "o" has become more flawed and on the most recent set I purchased they were fully filled and the crack could not be removed without removing too much material, leaving a visible, depressed line. I gave up and bought a set of PML's...

Good luck... GUSTO

leif.anderson93

This is what I know to be true, also, about the Paragon made aluminum valve covers.

GUSTO14

Here is a current picture of the remaining valve cover from the set I purchased in 1969 from Chevrolet. Unfortunately the other cover 'died' a horrible death in a small fire in the shop where we were doing a restoration in 2008. That along with a 900 cfm Holley 3-barrel carburetor.
Fortunately the engine was out at a machine shop being refreshed.


The casting flaw was fully raised (back then) and could have been removed leaving no visible flaw. Had I known then what I know now regarding this, I probably would have removed the flaw as others probably did. Had I done this, the same covers today could easily pass as original pre-flawed covers. Today it is good for wall-art in my garage.

JohnZ

I have a couple of sets of the C1-era 7-fin offset-hole, notched inboard flange 3726086 covers with the cast-in Hoover logo (yup, the vacuum cleaner people) on the inside.