Aluminum 7-Fin Valve Covers

[Michael H.]

I need for my early '65 the 7-fin valve covers WITHOUT the casting flaw line through the letter "o". From my search of the Archives here, I understand that the original valve cover molds were obtained at some point in the past by Paragon. In its parts catalogue, Paragon states that it refinishes valve covers manufactured off the O.E.M. tooling licensed to Paragon and that "The casting flaw, which passes through the 'o' in 'Corvette', has been removed in this process. If you require NCRS quality ask for a tech person before ordering."

In my research on this topic, I saw that there are a number of folks who restore (or "re-skin"--but apparently not literally) these valve covers. If I'm trying to pass NCRS judging, would I be better off buying an early set of original covers without the casting flaw and then having someone refinish them? Or would it be better to purchase the new Paragon covers that have apparently been refinished to remove the casting flaw? Has anyone here passed NCRS judging using the new Paragon covers? (Sorry, I looked, but didn't really find answers to these questions in the Archives.) Thanks in advance. Mike H.

[Larry M.]

Re: Aluminum 7-Fin Valve Covers

Mike:

I my opinion refurbished original is almost always preferred to new reproduction or replacement. I would first try and find a set of originals, and then if needed get them re-skinned. There are three or four folks that do this work now. If you cannot find/get the originals, then I would buy the ones from Paragon.

In previous days, the Paragon valve covers were quite rough compared to GM originals. To make it better, Paragon then offered a "polished" version, which also removed the casting flaw. Not certain if they have improved on this setup or not. Let's see what others say.

Larry

[Jerry P.]

Re: Aluminum 7-Fin Valve Covers

Mike...... when do you think the "flaw" first appeared ?

[Paul J.]

Re: Aluminum 7-Fin Valve Covers

Mike...... when do you think the "flaw" first appeared ?

That information is in the archives.

https://www.forums.ncrs.org/showthre...t=casting+flaw

I believe that it was first found in 66 production after March. It also became more pronounced as time went on.

Mike, buy a set of used covers and call John DeGregory or Jerry MacNeish.

Paul

[Michael S.]

Re: Aluminum 7-Fin Valve Covers


Thanks,
Mike

[Russ S.]

Re: Aluminum 7-Fin Valve Covers

Thanks,
Mike

And your point is...? It seems you are agreeing with the above posting.

[Michael S.]

Re: Aluminum 7-Fin Valve Covers

When I read the post in the attached link, I got the impression that it is common belief that the flaws did not appear until Mach of '66. Am I mistaken?

[Scott S.]

Re: Aluminum 7-Fin Valve Covers

When I read the post in the attached link, I got the impression that it is common belief that the flaws did not appear until Mach of '66. Am I mistaken?

Michael,

It has been my understanding that the casting flaw FIRST appeared around March of 1966, the mold was not repaired, so the casting flaw in the aluminum valve covers would remain through the end of the 1966 model year (June 1966) and be found on nearly all 1967 model year production (September 1966 through June 1967).

Regarding the March 1966 date, it is mentioned in the 1966 Judging Guide (p. 92). The current '67 Judging Guide mentions the flaw, saying most '67s have the line through the letter "o", but some early production cars may not exhibit the casting flaw on the valve covers (p. 73).

[Rob V.]

Re: Aluminum 7-Fin Valve Covers

Hi Michael--

What model year was the 350 hp red/red Corvette convertible that you mentioned in your posting?? That information might be relevant with regard to the point you were making...

Best Regards

[Paul J.]

Re: Aluminum 7-Fin Valve Covers

When I read the post in the attached link, I got the impression that it is common belief that the flaws did not appear until Mach of '66. Am I mistaken?

You are not mistaken. So what is your point and why are you arguing with this. We're always interested in new facts, especially those that disprove all written and understood beliefs.

I suggest that you consult the references that Scott made. You've been a member here a long time, so you should understand the efforts that go into the JG, and that most of it is well researched and substanciated. And yes, errors are found from time to time, hence my above comment about new facts.

[Bruce B.]

Re: Aluminum 7-Fin Valve Covers

Larry,
Concerning the rough surface condition on Paragon valve covers; The GM valve covers were also very rough.
I bought numerous sets in the late 1990's
I believe they all exhibited the same roughness since the Paragon valve covers were (are) die cast in the old GM tooling.
I'm sure processing variables had some affect, although the surface appearence was essentially the same.

[Scott S.]

Re: Aluminum 7-Fin Valve Covers

I'm not sure where the idea came from that the externally visible casting flaw through the "O" in the seven fin valve covers did not appear until March of 66, but I will argue the point. In 1967 I bought a 350 hp. red/red convertible.

Michael,

Was the red convertible you bought in 1967 a 1966 Corvette, or a '67 model year?

If your car was a 1966 (that you purchased in 1967), was the production date of your car earlier than March 1966?

Was the entire intake manifold painted orange, or were you referring to orange overspray around the base of the intake manifold?

[Scott S.]

Re: Aluminum 7-Fin Valve Covers

All,

For a photo reference, there is a nice pair of NOS pre-flaw valve covers in boxes with the old black and yellow GM label that Crane Corvettes has on the auction site right now: LINK

[Michael S.]

Re: Aluminum 7-Fin Valve Covers

I apologize; I left out one apparently very major fact about the red/red bought in 1967. This fact will now raise far more questions than it will answer. The car I bought was a 1965 350 hp. red/red convertible with both tops A/C, radio, heater and tinted glass. It was almost new with less than 10,000 miles.
The orange I was referring to was orange overspray on the aluminum intake that I tried desperately to remove with lacquer thinner.

[Michael S.]

Re: Aluminum 7-Fin Valve Covers