1972 LT1 engine piant sequence

[Jerome P.]

When was the aluminum LT1 intake manifold placed on the block? Was it before or after the block was painted? If it was before was the manifold masked to protect it from orange over spray? Did any over spray get on the manifold? In particular at the rear edges.

[Terry M.]

Re: 1972 LT1 engine piant sequence

When was the aluminum LT1 intake manifold placed on the block? Was it before or after the block was painted? If it was before was the manifold masked to protect it from orange over spray? Did any over spray get on the manifold? In particular at the rear edges.

Jerome,

The intake manifold, water pump, harmonic damper, and oil pan, but NOT exhaust manifolds or distributor, were on Flint built small blocks (ALL of them) in 1970-1972 when they were painted. There was a formed mask that fit over the aluminum intake on LT1 motors to shield the intake from the orange paint. The mask sometimes got blown a little bit to one side or the other during the orange paint operation, and a small band of overspray can sometimes be seen at the front or rear of the intake. Most of that overspray was subsequently covered by the aluminum paint that was applied to the intake manifold.

There were supposed to be "travel covers" that substituted for the cast rocker covers during the paint process, but I have seen numerous original LT1 valve springs and rockers covered in orange paint.

[Terry M.]

Re: 1972 LT1 engine piant sequence

When was the aluminum LT1 intake manifold placed on the block? Was it before or after the block was painted? If it was before was the manifold masked to protect it from orange over spray? Did any over spray get on the manifold? In particular at the rear edges.

Thanks to Ralph Spears, the photo below is of a (IIRC) 1972 LT1 head. Note the orange on the valve springs, and the mask for the spark plug holes and exhaust ports. This mask would be typical of ALL Flint built small blocks during the early C3 timeframe.

[Jerome P.]

Re: 1972 LT1 engine piant sequence

Thanks to Ralph Spears, the photo below is of a (IIRC) 1972 LT1 head. Note the orange on the valve springs, and the mask for the spark plug holes and exhaust ports. This mask would be typical of ALL Flint built small blocks during the early C3 timeframe.

Thanks Terry

[Lyndon S.]

Re: 1972 LT1 engine piant sequence

If one looks closely you can see what appears to be some chalk mark on the head. Great stuff thanks for posting it.

[Terry M.]

Re: 1972 LT1 engine piant sequence

If one looks closely you can see what appears to be some chalk mark on the head. Great stuff thanks for posting it.

Yep. Thanks be to Ralph. If I remember the story correctly those were new-car take offs by someone who thought angle plug heads would provide a power improvement. I think Ralph has a couple of other shots of those heads in his files. If you talk nice to him ....

Of course this just lights Mark Donnley's fire too.

[Mark D.]

Re: 1972 LT1 engine piant sequence

Of course this just lights Mark Donnley's fire too.

Oh, to accurately reproduce this quality would be a dream come true, for me.

Thanks Ralph and Terry!

[Jerome P.]

Re: 1972 LT1 engine piant sequence

Jerome,

The intake manifold, water pump, harmonic damper, and oil pan, but NOT exhaust manifolds or distributor, were on Flint built small blocks (ALL of them) in 1970-1972 when they were painted. There was a formed mask that fit over the aluminum intake on LT1 motors to shield the intake from the orange paint. The mask sometimes got blown a little bit to one side or the other during the orange paint operation, and a small band of overspray can sometimes be seen at the front or rear of the intake. Most of that overspray was subsequently covered by the aluminum paint that was applied to the intake manifold.

There were supposed to be "travel covers" that substituted for the cast rocker covers during the paint process, but I have seen numerous original LT1 valve springs and rockers covered in orange paint.

Terry, are you saying the aluminium intake was painted with aluminium paint subesquent to the block being painted? I always thought the intake had a natural finish.

[Sal C.]

Re: 1972 LT1 engine piant sequence

Hey Mark,

You're cars have too many valve cover bolts to have to worry about this detail. Unless you are holding out on me.

[Mark D.]

Re: 1972 LT1 engine piant sequence

Hey Mark,

You're cars have too many valve cover bolts to have to worry about this detail. Unless you are holding out on me.

No, No, I'm still in the 14 bolt club.

[Terry M.]

Re: 1972 LT1 engine piant sequence

Terry, are you saying the aluminium intake was painted with aluminium paint subesquent to the block being painted? I always thought the intake had a natural finish.

Yes that is what I am saying. 1970-72 LT1 aluminum intake was painted with a poor quality (soluble in gasoline from the leaking Holley) aluminum paint. The early 1970 LT1s were brush painted aluminum, but a couple months into production they used spray, and the aluminum spray application continued through the end of LT1 production in 1972. The aluminum paint was put on the intake after the bulk of the engine was painted orange.

Attached another shot of the other 1972 head from Ralph.

[Michael H.]

Re: 1972 LT1 engine piant sequence

Interesting! Of all of the original small block Chevrolet engines I've seen in my life, I don't recall ever seeing valve springs and misc other items under the covers that had orange paint from the factory.

[Terry M.]

Re: 1972 LT1 engine piant sequence

Interesting! Of all of the original small block Chevrolet engines I've seen in my life, I don't recall ever seeing valve springs and misc other items under the covers that had orange paint from the factory.

If those valve springs would have been under the covers they wouldn't have paint on them, Michael. Those, and the ones on my 1970, went through the paint line without any covers on them.

Restorers don't need to worry though. I doubt we will be asking owners to remove rocker covers any time soon.