1969 L88 question

[J W.]

Should the intake manifold on a 1969 L88 be painted silver or natural aluminum (or either)? The Judging Guide says natural but a NCRS judge told me most L88s came with silver painted intake manifolds. My inspection of several unrestored low-mileage L88s seem to support that as they appeared to silver painted manifolds. Also, should the thermostat housing and spacer be painted silver? Those low-mileage cars looked like the cast iron thermostat housing was painted silver as well.

[Michael H.]

Re: 1969 L88 question

Should the intake manifold on a 1969 L88 be painted silver or natural aluminum (or either)? The Judging Guide says natural but a NCRS judge told me most L88s came with silver painted intake manifolds. My inspection of several unrestored low-mileage L88s seem to support that as they appeared to silver painted manifolds. Also, should the thermostat housing and spacer be painted silver? Those low-mileage cars looked like the cast iron thermostat housing was painted silver as well.

I don't think any big block Corvette aluminum intake manifolds were painted dull aluminum.

[Joe L.]

Re: 1969 L88 question

Should the intake manifold on a 1969 L88 be painted silver or natural aluminum (or either)? The Judging Guide says natural but a NCRS judge told me most L88s came with silver painted intake manifolds. My inspection of several unrestored low-mileage L88s seem to support that as they appeared to silver painted manifolds. Also, should the thermostat housing and spacer be painted silver? Those low-mileage cars looked like the cast iron thermostat housing was painted silver as well.

Michael-----


I've seen many original Chevrolet aluminum manifolds that were painted with what appeared to be a more-or-less "dull" aluminum paint. Also, I once owned a 1968 Chevelle SS 396 with L-78 that I factory-ordered and purchased new. I'm 100% sure the aluminum manifold on that engine was painted with "dull" aluminum paint. I recall being somewhat upset about it because, at the time, I thought that aluminum manifolds were supposed to be "natural". However, I later observed many more that were painted, too. I don't know that all were painted, though. What I SUSPECT occurred was that any aluminum manifolds that were somehow "stained" in the manufacturing process (i.e. from the foundry, during machining, handling, or during assembly) were painted to make them look "factory new". Trying to clean an aluminum manifold, once "stained", to look factory new would have been virtually impossible so I believe painting was used. I suspect a large percentage of the manifolds would have gotten "stained" and required painting.

Considering the visibility of the manifold with the hood up, having it look factory-new would likely have been a lot more important than maintaining a "natural finish". And, if the manifold had been only partially painted (i.e. just to cover the "stains") that wouldn't have looked right, either.

The cast iron thermostat housings used on aluminum manifolds (e.g. L-88) were also painted with the same "dull" aluminum paint. I'm not 100% sure about the spacer but I think it was painted.

[Michael H.]

Re: 1969 L88 question

Michael-----


I've seen many original Chevrolet aluminum manifolds that were painted with what appeared to be a more-or-less "dull" aluminum paint. Also, I once owned a 1968 Chevelle SS 396 with L-78 that I factory-ordered and purchased new. I'm 100% sure the aluminum manifold on that engine was painted with "dull" aluminum paint. I recall being somewhat upset about it because, at the time, I thought that aluminum manifolds were supposed to be "natural". However, I later observed many more that were painted, too. I don't know that all were painted, though. What I SUSPECT occurred was that any aluminum manifolds that were somehow "stained" in the manufacturing process (i.e. from the foundry, during machining, handling, or during assembly) were painted to make them look "factory new". Trying to clean an aluminum manifold, once "stained", to look factory new would have been virtually impossible so I believe painting was used. I suspect a large percentage of the manifolds would have gotten "stained" and required painting.

Considering the visibility of the manifold with the hood up, having it look factory-new would likely have been a lot more important than maintaining a "natural finish". And, if the manifold had been only partially painted (i.e. just to cover the "stains") that wouldn't have looked right, either.

The cast iron thermostat housings used on aluminum manifolds (e.g. L-88) were also painted with the same "dull" aluminum paint. I'm not 100% sure about the spacer but I think it was painted.

Kinda funny that about 30 years ago, I was the guy that started the "dull aluminum paint theory" on small blocks and no one believed me then. Now, suddenly, it's the opposite. Most people now think all the aluminum manifolds were covered in silver paint.

Although I've never seen a big block manifold painted dull aluminum, or never noticed it, it's entirely possible that some were, just as you describe. I know that this process was used at the Flint engine plant in the 60's on small blocks to cover the area between the valve cover and the intake manifold on the cyl head, and also covered the thermostat housing and bolts.

For 65-67 Corvette big block with aluminum intake manifolds, there would have been no reason to paint the area of the cyl head between the intake manifold and valve cover because that area would have been painted orange. (along with some of the outer part of the intake manifold)
I don't know how that area was protected on 68 and newer engines, or earlier big blocks in Chevelles/Camaros etc because those cars would have had chrome valve covers and the head surface wouldn't have had the orange coating.

[Dick W.]

Re: 1969 L88 question

While anything might be possible (never say never) I have never seen what I thought was an original big block including a L/88 that I thought was painted. I have restored a couple of mid year small blocks, mostly untouched, that definitely had aluminum paint on the intakes.

[J W.]

Re: 1969 L88 question

Thank you everyone for replying. It seems as though L88s could have come with natural aluminum or painted intake manifolds.

[Clem Z.]

Re: 1969 L88 question

i think that they were painted to keep the cast iron heads intake surface from showing rust and since the L-88 had aluminum heads there would be no need for the aluminum paint. JMHO