[poncho-mike]

I have a question regarding relative value.

Let's say you have four standard bore 455 4-bolt main blocks. Say one is a 71 YE, one is a 71 WC, the third is a SR block with cast dates that mirror a 1971 production year, and the fourth block is a 1973. Assuming all are in equivalent condition (none are SD blocks), I'm trying to rank these from most desirable to least desirable, and estimate the difference in price between these blocks.

I have my opinion, but I'd like to hear other opinions.

Mike

[77 Canamman]

1.WC
2. YE
3. 1973
4 1971 SR

[weranc55]

WC 2k to 2500
SR 2k
YE 1500 to 1800
73 ?

[poncho-mike]

Originally Posted by 77 Canamman

1.WC
2. YE
3. 1973
4 1971 SR

Why would you value the 1973 4-bolt SR block higher than the 1971 4-bolt SR block?

['ol Pinion head]

Mike, Are both of the SR 455's std bore will go .030? Thx, Roger

[77 Canamman]

Originally Posted by poncho-mike

Why would you value the 1973 4-bolt SR block higher than the 1971 4-bolt SR block?

In your original post, you never clearly indicated that the 73 was a service replacement...

[poncho-mike]

Originally Posted by 'ol Pinion head

Mike, Are both of the SR 455's std bore will go .030? Thx, Roger

Assume all are 4-bolt standard bores, and will go .030" over.

Here is the reason for the question. I have a B121 YE 4-bolt 455HO block with a crack in one bore. It was replaced by the dealer and is low miles. The VIN is so badly stamped you can only make out the first few digits, the stamp was not square with the face when the VIN was applied. There are some pictures of it in a different thread..

I have someone interested in the block for a 71 Trans Am they own. He has a standard bore 455 4-bolt SR block with 1973 cast dates that he wants to trade for my YE. I'm not sure of the value of a 73 455 4-bolt standard bore block, since the cast dates are too late for a 71 or 72 Trans Am/GTO 455HO. I already have a couple of late calendar year 1972 and 1973 4-bolt 455 SR blocks in my basement.

The question also covers my 72 Lemans Sport convertible 455HO 4-spd. My car was shipped on April 15, 1972. I have a B292 WM block, which I'm beginning to think is too late for my car. I think I need a block dated closer to January or early February 1972. I have a 455 4-bolt SR block that I think is dated in December 1971. It's under a shelf and not very easy to get to. Which would be the better choice for my convertible? A SR block dated a little early, or a WM dated a little late? What would be the optimum date SR block for a mid-April built 72 455HO Lemans?

Any thoughts on what a 73 455 4-bolt standard bore block would be worth. My price needs to be adjusted for the sleeve needed, but I don't know what the value of his SR block is.

[Judge273]

I always thought SR blocks are to be later?

Correct blocks before?

WM is a block for M-22 72 455HO with unitized. B292 is Feb 29 1971 before April 1972 is correct?

I usually go by data plate for build...just me

As usual I'm confused on all this that and the other things...

NOM is NOM in my book anyways. Run those dogs as hard as you can or sell to people who want to pay....

[poncho-mike]

It's been my experience that most people want a service block with cast dates similar to what their original block would have been dated.

I think I have confused the issue by talking about two different but similar situations. I wrote the original post because I had a question regarding the difference in value between a 1973 455-bolt SR block and a YE 455HO block, assuming the blocks were similar. I have someone wanting to work a trade between my 1971 YE and his 1973 4-bolt SR block.

There have been recent posts discussing the typical amount of time between the cowl date, ship date, and cast date on engines. I bought a WM block before I bought the convertible, and there was a chance it was the original block. Several months back, I checked the VIN on my 1972 WM and found it was not the original block for my 72 HO convertible. My WM is dated B292 (leap day, 1972) and my 72 convertible shipped on April 15, 1972. So now I am wondering which block I should use in my 72 convertible with a April 15 ship date. My choices are a Dec 1971 SR 455 4-bolt, a B292 WM block, or a Feb 1973 cast date 1973 455 4-bolt SR block.

Mike

Two different topics, same concept.

[skunkwerks]

Mike,
I would use the 73 SR block for the Vert. This is assuming you do not have the NOM motor for this car. SR motors were warrantee motors and usually have a date code later than the trim tag date on the car. Replaced at the dealer under warrantee work. Only thing better would be the NOM or a WM block with no VIN stamp with the correct date before the trim tag build date. JMO.

Originally Posted by poncho-mike

It's been my experience that most people want a service block with cast dates similar to what their original block would have been dated.

I think I have confused the issue by talking about two different but similar situations. I wrote the original post because I had a question regarding the difference in value between a 1973 455-bolt SR block and a YE 455HO block, assuming the blocks were similar. I have someone wanting to work a trade between my 1971 YE and his 1973 4-bolt SR block.

There have been recent posts discussing the typical amount of time between the cowl date, ship date, and cast date on engines. I bought a WM block before I bought the convertible, and there was a chance it was the original block. Several months back, I checked the VIN on my 1972 WM and found it was not the original block for my 72 HO convertible. My WM is dated B292 (leap day, 1972) and my 72 convertible shipped on April 15, 1972. So now I am wondering which block I should use in my 72 convertible with a April 15 ship date. My choices are a Dec 1971 SR 455 4-bolt, a B292 WM block, or a Feb 1973 cast date 1973 455 4-bolt SR block.

Mike

Two different topics, same concept.

[eaglesan13]

I would use the WM block in the vert if that is the correct block code for the car. The block was cast six weeks before the car was built, and that's just fine (in my opinion). I personally would rather have the correct block code as opposed to an SR block, but that's just me.

[The Boss]

I would use the WM block as well. Convertible was built at the Pontiac Plant and the foundry & engine lines were right there on property. That date range wouldn't bother me at all.

[John V.]

SR cylinder block assemblies were Service Replacement, they weren't only for Warranty installs. Meaning a car out of warranty could still be serviced using a SR cylinder block assembly. You had to buy the part from the dealer, but you didn't have to pay for the dealer to do the work. Anybody could buy one, no different from buying a Water Pump Assembly from the dealer. They are associated with Warranty repair because by the time the original engine wore out on most cars, people didn't usually buy a new SR cylinder block assembly, they went to the salvage yard for a good running replacement or junked the car. Usually only if PMD was paying the bill under warranty would a cylinder block assembly be supplied.

Many times, the block that was part of the SR cylinder block assembly was not even the same casting p/n as the original block as PMD could use a current production block to produce a SR cylinder block assembly. For reasons unclear to me, PMD would sometimes (or always) grind off some or all of the current production block casting p/n and stamp a p/n to duplicate the original block casting p/n. The only reason I can think for why they did this was so that the purchaser would not think he got the wrong block. Also conceivable that it was to indicate that the block was machined according to the original block p/n if somehow the current production block p/n was using some different machining. This is just guesswork to try to explain why PMD bothered to stamp a particular p/n on a block made part of a cylinder block assembly. It seemed totally unnecessary to do so to me.

Note, PMD did not ever sell bare blocks for Service Replacement to my knowledge.

From a value standpoint, my opinion has been that a SR block devalues a car same as any other replacement block would. Neither would be original. I agree with Judge273, a Not Original Motor (NOM) is a NOM. If the original Work Order paperwork documenting a specific SR block by its stamped nos. that replaced the original engine block was retained with the car, I would add value for that, but still consider the car to be devalued relative to a nos. matching engine.

As an aside, that is why I am suspicious of any claim of a nos. matching engine. If it increases value, as I believe it does among the vast majority of hobbyists, it must hold up to close scrutiny.

In my view, it makes no sense for the SR to have a similar cast date as the original block.

In most cases, the SR under warranty would have been made as a last resort after exhausting all other attempts to remedy the problem. High oil consumption as example would first require sufficient ring break-in time before deciding a cylinder block assembly under warranty was needed.

And obviously, an out of warranty SR would figure to have a block cast long after the original.

I would much rather have the correct Engine Manifest Code on the block with a reasonably possible cast date than any SR block by a WIDE margin. Only exception would be the SR block fully documented as having been installed in or out of warranty when the car was much newer with complete dealer service work invoice papers, etc. Putting a SR block in a 45 year old car to make it appear as if it was the recipient of a long ago SR under warranty without documentation makes no sense to me and would carry same value as any other block that had no rhyme or reason for being there, ie., wrong Engine Manifest Code, impossibly wrong cast date, and wrong casting p/n.

Things began to change during the '70s and I know a whole lot less about the relationship between block cast date and vehicle Time Built code for a '72 than I do for a '64, but a B292 date for an April '72 built car if anything seems too early, not too late.

I assume it was April built. Ship date is irrelevant. The Date Shipped for Zone Stock builds could be days, weeks, or even months after the car was final assembled and originally shipped into the Zone. Such Zone Stock builds will show a "Date Shipped" on the dealer invoice when the car was first wholesaled to the retailing dealer after having sat for whatever amount of time in a Zone storage facility. In such cases, the VIN and Time Built code must be correlated to establish when the car was actually produced.

For production in the '60s, it was not unusual for Engine Assemblies to go from the Engine Assembly Plant to install in a build on the Final Line with just days between the block cast date and the date of final assembly. This was relatively true even at the remote assembly plants, didn't take long for engine assemblies to be shipped from Pontiac, Mich to the remote Final Plants and get installed. This tended to be the norm, while the exceptions are less common where several weeks or even months went by before a long completed Engine Assembly finally went into a build.

I'm with eaglean13, if the original Engine Manifest Code for your convert was WM, I would rather see it installed than one of the SR blocks. If the original was not a WM, then it really doesn't matter in my eyes, I'd use the one in best condition.

If you want to get an idea of whether the cast date of the WM is plausible for the build date of your convert, check the VIN stamp and then determine when THAT car was built.

You may be surprised to learn how close to the build date of your convert that it turns out to be. The fact that the WM was a unitized K65 option Dist Engine Manifest Code might skew the result, I don't know how rare that code is. Sometimes (not always), rare Engine Codes would languish in a Final Plant engine assembly inventory for longer periods because they were so rarely ordered.

But the VIN on it will give you an idea of what was possible for lag time.

[poncho-mike]

John V,

Thanks for the detailed response. The April 15 date is earliest date shown on the PHS. The car is stored 120 miles away, and I can't seem to remember to check the cowl tag and see what the trim tag shows as the body build date.

Mike

[John V.]

Mike, look at the Identification No. on the Dealer Invoice PHS record.

If the first character is a "P", the car was sold and invoiced to the Ship To Dealer essentially at the moment it rolled off the Final Assembly line.

If the first character is a "Z", then it was not immediately sold to a Dealer. In that case, the car was initially shipped to and "owned" by the Zone for a period of time before being sold to the Ship To Dealer. In this case, you will need to check the VIN and Time Built code to know when it actually rolled off the Final Line.

[Formulabruce]

Originally Posted by poncho-mike

It's been my experience that most people want a service block with cast dates similar to what their original block would have been dated. .

While I do agree, this makes Zero sense. Maybe they will choose the words "period correct " as a choice when selling? Having installed these, I have seen SR Short blocks dated in 1977 for a 1973 455, or 400, or even a SR 350 dated 73 for a 71 and that "73" SR had serious dust on the bag/ box when it arrived.
There were NO SR Blocks that Fit a Production date unless it failed at Final, and was sent to the unfinished car lot, Youll see a VIN stamped on it then. Date could be closer.
"Period correct" in Reality, for an SR Block would be its warranty period.
Never saw a bare block at parts, due to Pontiac dealerships didnt have balancing equipment. SR blocks were short blocks usually., Bare crate blocks were usually well after warranty and left over supply, OR RA V stuff .

[unruhjonny]

I have understood, as has been my approach, that when an original engine is missing, the order of desirability looks something like this:

1) correct code, correct model year, correct date range
2) correct code, correct model year
3) SR; correct model year casting number
4) SR; later model year casting number
5a) wrong engine code, correct model year, correct application (eg: 455HO block for original 455HO car)
5b) correct engine code, wrong model year (eg: 1969 YZ vs 1970 YZ)
6) wrong engine code, wrong model year, correct application (eg: 455HO block for original 455HO car)
7) wrong engine code, wrong model year, correct configuration (eg: 4 bolt main block, in original 4 bolt main application)
8) correct displacement only

With all that being said, my opinion as to which engine might be worth the most (order of desirability):

1) 1971 WC (455HO/4 speed)
2) 1971 YE (455HO/auto)
3) 1971 SR (ideally suited for a 1971 car; but also correct for a 1970 car)
4) 1973 SR (ideally suited for a 1973 car, but also correct for a 1970-1972 car)

I too agree that NOM is a NOM, but I would also assert in the same thought that a 100% correct would be ideal - and the closer to correct, the smaller the overall depreciated value of the car.

[unruhjonny]

Originally Posted by John V.

... In my view, it makes no sense for the SR to have a similar cast date as the original block.

...

I wholly agree.

[poncho-mike]

I suspect that the people looking for a correct cast date SR block may be intending to re-stamp their VIN and engine code.

I have a January dated 1973 SD455 block with no SR or VIN numbers anywhere on the block. I have someone who wants to buy it very badly for their 73 Trans Am. I also think they have the original SD455 motor but it is damaged beyond repair. I suspect my block would become the numbers matching block for that car if I should sell.

I'm still not sure what the approximate difference in value between a 73 4-bolt SR block vs a 71 YE block.

Mike

[Judge273]

Just asking Mike,

See lots of your threads asking prices on parts, and lots of people lined up to buy your blocks.

Do you ever sell these things.