Bowtie73

Hi All,
Can anyone identify these cast valve covers for me?
They are on my NOM '58.
A quick check of engine bay images online shows the nearest similar type is the '69-era Camaro but the Corvette flags indicate perhaps otherwise?
Maybe its an aftermarket product or perhaps C3 era- I'm no expert on the '60-70's factory SBC's offerings.
Thanks in advance for any suggestions

Todd H.

I think the original valve covers on my '69 350/350 Corvette were like that.

Chuck Gongloff

I believe they are referred to as LT 1 valve covers. 69 and up Corvette and Camaro IIRC.

I had a set on my 37 Chevy hot rod.

Bowtie73

Cool, thanks for the quick reply!

Bowtie73

Ok, So I have checked the engine casting number (*****CKZ) and consulted the online decoder, and it looks like it could one of three possible versions with a 'CKZ' suffix:
A '72 LT-1 350 4 spd manual,
A '73 or '74 or '77 base-spec 350.
Any ideas on how I can tell which one or if it's something else (e.g. 327)?

KingRat

They are the valve covers that were put on the optional, high(er) performance small blocks from '68-'77. So if the buyer bought the L79 in '68, L46 in '69, LT-1 '70-72, L82 '73-'77 the factory dressed them up a bit from the painted orange valve covers. In '78-'82 they were painted black.

Mike C#2

You can't tell displacement from the outside. But you can pull a valve cover and figure out what cylinder heads you have. Casting dates would let you know the odds of it's displacement as well.

An LT-1 would have screw in studs and guide plates. Same would be true for an L-82 if that's the motor source. Base model motors would have press in studs. What is cylinder head casting #? This is assuming a long black was installed and not a short block with who knows what peripherals used.

What intake manifold is on the motor? Balancer diameter and width?

IME, you won't have a 327 with a 39270010 block casting. It could be possible but 99% will be 350. Large journal 327 were only in 68 and 69 and 69 model years, they turned into 307 around first of the year. 307 crank can be used to build a 327 using a 4" bore block.

I have a .030 4 bolt main 327 in my '72 Jimmy that was built from a '72 high nickel block and a '69 large journal 327 crank but it didn't leave GM at that displacement.

kobi67

Early covers had a push-in oil fill plug and the cuts to clear the intake runners on the one side were equal length. Early style bring more $$.

emccomas

The push in oil plug was 1971-1972 only for small block valve covers. This was true for the stamped steel valve covers as well as the optional engine aluminum covers.

BKarol

The shape of the engine pad will tell you part of the story. In mid 1977 they went to a squarish pad and if that is what you have then it is the 77. However it doesnt rule out an earlier 77 engine but only if it has this shape you can rule out the rest.

tuxnharley

What is the complete list of all characters on the engine block stamp pad, at the passenger side front of the block? Those characters will tell when the engine was assembled. The partial VIN will be a clue as well.

JohnZ

That's a popular misconception - there was no such thing as a "high-nickel block". The "010-020" cast into the bulkhead behind the timing cover doesn't refer to the level of nickel alloyed into the grey iron block - that never changed - it simply identifies the core section that formed that forward bulkhead, and indicates that it was used on both the 3970010 and 3970020 blocks in the core department.

Bowtie73

Thanks everyone for your help
John Z, great to see you back on the forum!

I think I have worked it out with the info CF members have supplied, the internet and an afternoon spent crawling over the car (and pressure washing the engine).

The Engine stamping is V0416CKZ and 13S421348.

So (if I have this correct?), based on the above stampings it looks to be from a St Louis-built 1973 Corvette with a 350-cid 190-hp V-8 with 8.5:1 compression ratio, manual transmission, and four-barrel carburettor. Production unit number 421348. Not sure what date the car rolled off line based on this?

The block was cast in Flint on 16th April, 1972 at around lunchtime.
The 'clock' cast shows it to be 1/2 way around from the start of the 10hr shift (06:00hrs).
The manual trans may also be the matching original (still to be confirmed).

It will be removed from my car in near future, would be great to make it available to return to the original owner if you know how I could find that out (I guess a long-shot)?

The engine itself runs great, also has LT1 valve covers and aftermarket headers, Edelbrock carby and intake.

I have posted the details under the 'Orphan' VIN parts page over in the C3 section, hopefully someone needs this one!

DZAUTO

The VERY FIRST usage of that style finned alum valve cover was NOT, repeat, NOT on a Corvette. Those covers were first installed on the 69 (NOT 68) Z/28 Camaro (302 cubic inches) engine, and continued on later Z/28 engines.
Then for 1970, the LT1 Corvette engines got them, and continued on with them for several years.
There are multiple versions of the 69-later finned alum covers, and a person has to be familiar with the subtle changes which occurred through the years. (such as the push-in rubber oil filler cap for 71-2 and the longer notches for the intake manifolds with EGR valves beginning in 73). OUTWARDLY, to those not familiar with them, they look the same.
There was NO, repeat, NO finned alum valve covers for small blocks in 68. BOTH the 68 Z28 (as well as the 67 Z28) and optional Corvette engines got CHROME valve covers for 68.
In my book, the VERY BEST versions are the 69-70 covers which used a twist-on chrome oil filler cap and the shorter notches for intake manifold clearance.
The covers used on both the Z28 and Corvette engines had the crossed flag emblems.

jrs 427

They have been mounted on many small block engines by owners they are quite common. Not a rare commodity, just another small block dress up item. I prefer painted, lean look, competition inspired examples. ( I forgot to get the L-79, L-72 lingo in there )

tuxnharley

Hmm, well, I think you are real close, but there are a couple of details left to clear up.

The V0416CKZ means the engine was assembled on April 16. That is not the block casting date. It would be outside the norm for a block to be cast and the engine assembled on the same day, especially if it was cast around noon time.

For a 1973 car - which the partial VIN shows it was - of a production sequence # 21348 out of a total of 30464 Corvettes made that year -the engine would have to be from April 1973, not 1972. (detail note: although the 1973 Corvette VINs ended in 34464, only 30464 were actually produced as VINs in the range from 24000 to 28000 were never used)

The CKZ means it was a L48 190 HP engine with a 4 speed transmission.

I think you may have misread the 1 in the first digit of the partial VIN you provided from the engine stamp pad, which is an engine designation code. For that to correspond to the CKZ engine designation it would have to be a J. The only characters used that year in that location were J for L48 350 190 HP, T for L82 350 250 HP, and Z for 454 275 HP.

I commend you for your efforts to reunite the engine with the car. I think that is a real long shot, as the L48s were real common - about roughly 20,300 of the 73 Corvettes - and many were wrecked, stolen, salvaged, etc. My guess is your engine likely came from a car that no longer exists.

Have you tried looking in the Corvette registry for that VIN 1973 Corvette?



PS - I just looked, it is not listed in the C3 registry.

emccomas

The 1973 Corvette (either coupe or convertible) is NOT listed in NMVTIS.

gbvette62

I'm going to disagree with you a little bit on this.

The 69 Z/28 was not alone as the first engine to use those covers. Both the 69 Z/28, and 69 Corvette L-46 350/350, came with the finned aluminum valve covers.

gbvette62

The OP has the VIN derivative correct.

In 73, the VIN derivative started with a "1" to indicate the Chevrolet Division, followed by "3" for the model year, "S" for St. Louis, and then the sequential serial number. The VIN engine identifiers of "J", "T" and "Z", only appear in the full VIN number attached to the a-pillar, they are not found anywhere on the engine.

toddalin

IIRC, there are "drippers" placed above the valve springs that are not found on the stamped steel covers.

Shown here on my '64 painted with "crinkle" paint and ribs are then "sanded" with an emery board.