1969 Camaro SB Exhaust Manifold Bolts

[Edgemontvillage]

When I purchased my '69 Z it had a few Day 2 parts installed including headers.  I located a set of date coded, original exhaust manifolds (and smog system) to replace the headers however I used new, commonly available replacement bolts. I have not been able to locate a photo showing close-up head details of assembly line correct SB exhaust manifold bolts and recently came across the photos below.  The head detail on these early bolts is similar to the reproductions however they do differ somewhat. Note a single ring and N stamping which I assume identifies the manufacturer (National?).

 - Has anyone come across these early bolts, are they assembly line correct or incorrect service replacements?

 - Does anyone have close up photos of original, assembly line installed exhaust manifold bolts?  

Reproduction SB Exhaust Manifold Bolts


Early Manifold Bolts - Original?

[1968 Z28]

Lloyd....don't know for sure about the '69 but my original '68 Z28 has two different manufacturers for the exhaust manifold bolts.  One side had the raised circle bolts with a "RSC" inside the circle.  The other side had a flatter circle on the head with a squiggly "X" inside the circle.  My computer that has my camera software on it is down right now so I can't send a photo at present.  Will try later tonight when I get it back up, that is if your interested.

[Edgemontvillage]

Lloyd....don't know for sure about the '69 but my original '68 Z28 has two different manufacturers for the exhaust manifold bolts.  One side had the raised circle bolts with a "RSC" inside the circle.  The other side had a flatter circle on the head with a squiggly "X" inside the circle.  My computer that has my camera software on it is down right now so I can't send a photo at present.  Will try later tonight when I get it back up, that is if your interested.

Yes, I'm interested Jerry, please post photos when you can.  I would like to see examples of head markings from a few known original cars as well determine if the photos of the bolts I posted are correct.

[JohnZ]

Lloyd....don't know for sure about the '69 but my original '68 Z28 has two different manufacturers for the exhaust manifold bolts.  One side had the raised circle bolts with a "RSC" inside the circle.  The other side had a flatter circle on the head with a squiggly "X" inside the circle.  My computer that has my camera software on it is down right now so I can't send a photo at present.  Will try later tonight when I get it back up, that is if your interested.

Yes, I'm interested Jerry, please post photos when you can.  I would like to see examples of head markings from a few known original cars as well determine if the photos of the bolts I posted are correct.

Each engine plant used 66,000 exhaust manifold bolts every single day, and you can bet they didn't all come from the same supplier; this is recognized in NCRS Corvette Flight Judging.

[1968 Z28]

Lloyd....two different manifold bolts on same engine....

     

[Edgemontvillage]

Interesting head marking detail, thanks Jerry.