I recently bought a '72 Stage 1, it is missing its original engine and transmission. I've sourced a date code correct carb and I believe a correct 1112016 distributor. For cylinder heads, given the low numbers of Stage 1s produced in '72, I would think the casting dates for heads are limited to a few days during the production year. Are those dates well known?
Not that I am aware of, the only way to confirm any year Stage 1 heads is to actually see the valves, head castings are all the same for each prospective year application. And the easy way without having a way to measure is with a dime, it will not fit between the exhaust and intake valves, old school. And as a side note on your carb, date doesn’t indicate a Stage 1 carb, the # is 7042242 or 7042942 if memory serves. The Stage 1 registry site can help you out also with information
This thread discusses unshrouded valves. Head castings are the same as non-stage, but Stage1s would have a factory unshrouded area. https://www.v8buick.com/index.php?threads/stage-1-heads.252112/ Troy
Yes, when the heads that are currently in the car were pulled, they were not Stage 1 heads or converted as the valves were spaced apart. The reason I ask is I’m more familiar with Pontiac round port heads in particular Ram Air II cylinder heads, very different castings so they were cast on only certain dates and which dates tell you if they were made for production or as service replacements. Since the castings for the Stage 1 heads are the same as the normal heads, there may not be specific dates for the Stage 1s. However, the machining operations would be different to get the valves located correctly. Would this be done on any day? Or would they do 100 at a time so that the dates for all January cars would be a day in December? Yes, the carb I have is a 7042242 carb with a date code prior to the 1E build date on the cowl tag.
In speaking with a quality engineer who oversaw the cyl head line back in the day, I can confirm that the specific Stage 1 machine work and assembly was done in batches, though I don't know how many per batch or the frequency of the batches, sorry. Devon
Are they even date coded on Buick heads? I have never heard anyone ever ask that question or discussed. 1972 Year heads will have 72 cast on the #1 exhaust runner, but only seeing the valves can you tell is they are Stage 1 as I said before, and the un-shrouding as Troy discussed above.
I'm a bit surprised it hasn't come up before either. Perhaps because the numbers are hidden by the valve covers. Again, most of my experience is with Pontiacs where the numbers are readily visible with valve covers on and so verifying correctness is simple. There are 48 heads with a casting date of August 15th of 1968, and are correct for certain GTOs. Wouldn't this be the date code to matchup with a set of 1238148 heads? Of course any set of those can be modified to Stage 1 valve spacing. But only some would come from the factory as Stage 1 heads. Without the correct date codes, almost no way to tell.
Not really true on not being able to tell which have been converted to Stage 1 and which are factory, as stated before ALL factory being unshrouded and can easily be seen, almost never ever has there been a case of converted heads being UnShrouded.
I don't know what you're talking about. Stage 1 heads are the same as non stage, minus the machining, because that is how the factory did it. Took bare head castings and machined the appropriate valves to fit. Any decent machine shop can do this. They have the same casting numbers for a reason.
Not saying they are different other than the machining. But that is the point, the machining is different. They aren't custom building these cars/engines one at a time. These are production operations (even the machining); generally you do things in batches. Which is exactly what Devon said. This is the key piece of information. Buick isn't sending out a single set of bare castings down to the local machine shop, here put these 2.125 and 1.75 valves in with these springs. These are not custom built cars. They are sending 210 bare castings with casting dates of G8 through G10 with the correct valves and springs to their machine shop and expecting to get 105 sets of heads for the next 105 Stage 1 engines to be built. It appears we don't know how often this was done so would need to get the casting dates from as many cars as possible with known original Stage 1 heads along with production dates, plant codes, etc. to get a better understanding of batch size and frequency. Yes 210 is a made up number. In other words, this is easily faked, if my car currently doesn't have correct heads? I contrast this with the distributor situation, where Buick apparently told Delco a few weeks ahead of June 23rd of 1970, that they need 1,500 1112016 distributors to cover the rest of the '70 model year, the '71 model year, and much of the '72 model year production of Stage 1 cars. If Buick knew they were only going to produce no more than 853 Stage 1s in '72, why not make all the heads at one time? It is more efficient and likely better quality that way.
Because Buick ultimately wanted profits, and heads are expensive compared to distributors & carburators.
