[A Schab]

This kind of reminds me of a guy named Jeromy and a certain test car.

[necdb3]

This shows how you must do your homework when buying a car from someone. There are so many people who would be willing to misrepresent a car for their financial gain.

The bottom line is, If he (thews) sells this car someday as numbers matching and a buyer takes him to court, He (thews)will find himself on the losing side of the law.

I think you guys are wasting your time trying to convince him of that.

[The Boss]

Originally Posted by A Schab

This kind of reminds me of a guy named Jeromy and a certain test car.

^ This ^

[Bet Winner]

The numbers that match another number on a car are the VIN's on the block and transmission (and frame I believe) matching the VIN plate on that same car. If these do not match each other, the answer should be self-explanatory.

[The Boss]

Originally Posted by Bet Winner

The numbers that match another number on a car are the VIN's on the block and transmission (and frame I believe) matching the VIN plate on that same car. If these do not match each other, the answer should be self-explanatory.

YOU said I believe!!! Are you making this up??? Where is your proof??? Does that mean in your opinion... ???? What a gigantic load of BS.

[John V.]

Originally Posted by thews

...you're nothing more than owners of low mileage originals that have nary a clue what it's like to actually build a car. Where is the damn line? If your radiator cap is incorrect, is your car then not numbers matching? Please answer the question asked without a load of conjecture based on your opinion.

1. My car, a '64 GTO convert, is not low mileage, is not even close to "all original", and I have the utmost respect for everybody who enjoys the old car hobby, regardless of the make or model of car and/or whether they built or bought it and/or whether it is mostly original, restored to factory correct, mildly modified, or a radical custom.

2. Your question about the radiator cap illustrates your ignorance about the term "numbers matching". For fear that you will not understand the meaning of ignorance, it is not intended as an epithet, it simply means you are showing a lack of understanding.

As I explained in my previous post, "numbers matching" is a broad descriptor. It means different things to people in different parts of the old car hobby. In the 1st gen Firebird segment of the hobby, if you say "numbers matching engine", I would expect the block to be original with all identifying codes whether cast or stamped to match the original without any indication of being tampered with so that it would be accepted by the vast majority of 1st gen Firebird enthusiasts as being the original block. But if you claim "engine" and not just the "block", I would expect every other component that was part of the original engine assembly as produced at the Pontiac Engine Assembly Plant for that car to pass muster with respect to p/n, date code, and any other distinguishing feature so as to convince the vast majority of first gen Firebird hobbyists that the parts were likely original to the engine assembly or close enough substitutes for the original pieces. I would also expect all items that were added at the final assembly plant during engine dress-out to be original or again, close enough substitutes. For example, fan, pulleys, alternator, bracketry. spark plugs, plug wires, coil, and so on.

This article echoes what I am trying to explain to you:

http://www.newsday.com/classifieds/c...sals-1.6154213

Usually nobody would describe an entire car as "numbers matching".

So your radiator cap question is flawed.

The radiator cap can be described as "original" if it is. Or it can be described as "correct". If "correct", that is taken to mean what is believed to match what was "original" within the first gen Firebird hobby. There can be disagreement within the hobby. There can be variation. There can be running changes. Certain details reach a point where nobody is 100% sure and there may be no consensus. In judging, there may be acceptable alternates. Sometimes there are cases where an original owner claims a component was original to his car but judging considers it wrong. Just the way it is.

If the radiator cap is obviously incorrect, in concours judging, a deduct would be assessed.

An incorrect radiator cap would have nothing to do with whether a block, an engine, or a drivetrain can be described as "numbers matching".

You want a hard and fast rule.

This has been repeatedly answered.

Specific to whether a '69 Firebird block can be described as a "numbers matching block". The definition that the majority in the first gen Firebird hobby would adhere to is that the block must be stamped with the VIN matched to the car.

For the block you have, it would not be accepted as a "numbers matching block" because it does not have the matching VIN stamp.

As I mentioned, it is probably not a good date code match for your build date either.

And I would want to investigate the lack of the 7 digit EUN stamp further. This might indicate a restamp which would make the WN engine manifest code stamp suspect.

Assuming the original VIN stamp is on the block, it would be possible to pull the PHS invoice record to see if that VIN was built with the man trans 350HO option. That seems silly to me because the 350 blocks were all the same (until late year anyway) but you could do it. Whether the block was originally part of a WN engine assembly isn't very important to me, but if you wanted to document it, you could.

But I'd still like to resolve the lack of 7 digit EUN. That shouldn't be too hard to do.

You can argue all you want about the definition of "numbers matching block" for a '69 Firebird.

What you are being told is that the block you are calling "numbers matching" does not carry the value that an "original" block would carry. The "original" block is what the majority of first gen Firebird enthusiasts would refer to as the "numbers matching block".

As I mentioned in the previous thread, it is this difference in valuation that has given rise to the practice of restamping.

You could restamp your block with the matching VIN. If it was done very well, it would be virtually undetectable.

But you should know that many hobbyists consider this highly unethical.

It is also illegal in most or all states. The likelihood of being caught is pretty slim but people have gone to jail for VIN tampering on old collector cars.

And it is being widely done according to what I read. That is why when I research nos., I have learned to put little stock in what is represented by restored vehicles.

To illustrate, if you restamped the VIN on your block, it would appear that an early Oct block was used in a January built '69 Firebird. But if I studied 100 unrestored January built 350 Firebirds and every one of them had a December or January cast block, I would look at your block as an outlier that was most likely a restamp.

Worse yet would be if you had documentation by P-O-P or other means that showed the original EUN and you restamped the block to match that EUN too.

And if I then studied EUNs close to yours from all Pontiacs including many 350s and they all had December or January cast blocks but yours was early October, again, I would chalk it up as a likely restamp and not useful to my study of EUNs.

Others aren't as fanatical and would never dig so deep into the numbers. That's okay by me.

My hot button has always been "factory correct". That is what I enjoy most in the old car hobby.

So I admire most when anybody makes extraordinary efforts to represent a car as "factory correct".

This includes "numbers matching" engine and drivetrain components, date code correct glass, and, yes, correct radiator caps.

Some guys like original low mileage "survivors". Some like restomods.

So it takes all kinds.

I don't know why you won't accept that a block with the wrong VIN is not called a "numbers matching block" in the first gen Firebird hobby.

It sounds like you are trying to replicate the original engine as close as possible. I would call what you are aiming for as being as close to factory correct as possible.

I applaud that and I appreciate the difficulty especially when you are also trying to come up with reasonable date code pieces.

I don't know what cast dates are available for the 48 heads or what would be a reasonable date code for your car.

But I suspect a January build 350HO car would have had December or January cast dates on the heads of the original engine assembly.

IMO, later cast dates won't be a good match to the early October cast block but if it was me, given the choice, I'd opt for heads that were more likely a close date code match to the originals based on the build date of the car vs. attempting to date match the heads to the non-original block.

Especially since I get the impression that your October cast heads might still have been cast too late to have been original to the EUN on the block.

The 6 digit EUN remains problematic.

[Bet Winner]

Originally Posted by The Boss

YOU said I believe!!! Are you making this up??? Where is your proof??? Does that mean in your opinion... ???? What a gigantic load of BS.

Well, that's how I do it...........................lol

[RamAir]

John V, I commend you for taking the "High Road" on this topic/thread.


Sent from my iPhone using Tapatalk

[68bird400HO]

John Vs comments are spot on except I disagree with his opinion on what an appropriate date code spread should be for this car. On high production cars like your standard lemans, firebird or even GTOs where 10s of thousands were made, I agree that the date codes should be pretty close as the parts were going out the door as fast as they were coming in. However, on lower production cars, like a 350HO, or esp any RP car, the date code spread is likely longer. I don't think you can analyze date code spread patterns of high production cars and just apply those rules to all.

[jinxd68]

i agree with what John V has said in his comments. Can we throw my 68 400 convert up for discussion? The car was built 12D( december 4th week). the block is has the vin stamped on the pass side lower that matches the vin on the dash as does the transmission(turbo 400 if it matters). The block is coded YT and has a date code of L207(december 20 1967). the intake manifold is 9790140 date code L137. carb is correct 7028264(no julian date). now here is the kicker on this car. the heads are casting #15 BUT the date codes are L067. To me the heads are incorrect casting numbers for this car. the exhaust manifolds have also been changed to a mismatched set of 69 gto and firebird as well. I have located a correct casting number 16 set of heads with a date code of L017. Is my car now "numbers matching" and "date code correct"? In my opinion yes. I don't understand the EUN if someone can please explain how that works i'd appreciate it. Now I also have a WZ block(4spd bird) with a date code of L017(bought with the heads for the auto car). IF I was to put this engine in my convert, found a date coded and application code correct trans, would this now be considered "numbers matching" and a "date code" correct "RECREATION" if i had all the correctly numbered parts?

[John V.]

I agree with you in general. However, the 4 bbl small motors (326 or 350) were always slow sellers. I mentioned the '64 326 anomaly, 10 week spread, it was a 4 bbl. But other '64 326 HOs were close.

I think you would find the same thing for '69 too.

Since they were slow sellers, they didn't produce a lot of them for inventory either. Somehow they managed to align engine assembly production with the demand for that engine at each plant. Consequently, they might show a spread on one build but not on others. Example, maybe the Plant received 10 350 HOs for inventory. They built 7 350 HO cars within 3 weeks of receiving them. Those cars would have relatively close date matches. But then they hit a lull, building 1 every other week. Would be 6 more weeks before the last of that inventory got installed. And since they didn't use first in, first out inventory control, they may have received 6 more engines before the last one was built and those newer engines might have been installed before the last of the old batch was given a home.

You say the spread was "likely longer" for the less common engine codes. I can only say that based on the research I have done for '64 Pontiac engines, that isn't true.

It might be true that less common engine codes were more likely to be the ones that have the longer date spreads when a large date spread is found, but they aren't generally longer.

'69 was different from '64 in that there was a greater proliferation of "less common" engine codes. RAIVs, unique 'bird engines, all of which didn't exist in '64.

Total Pontiac production had also increased by about 1/3 vs. '64. Don't know if that helped or hurt.

So there really aren't any hard and fast rules for date code spreads. For years I have listened to guys try to make claims about what was common. And it was never borne out for '64. Most had no idea how close the dates were for most builds in '64.

I have not studied '69 engine dating vs. Time Built codes as I have for '64. So you may be correct. I just think unless somebody undertakes that research, safer to stay closer.

I noted the spread for your original engine. Doesn't surprise me.

And it probably can be attributed to the relative low production of your engine option, perhaps also where it was final assembled. But I'd bet that others with the same engine, final assembled around the same time and at the same plant would have a much tighter date "match".

Assuming that was the case and if you DIDN'T have the original engine or any info about it (such as the EUN), I just think you would be better off choosing a closer date rather than assume an unusual outlier.

I qualify this by saying, we can be certain that a March assembled engine was not the original engine in a car built 4 months earlier. But as long as the engine was assembled prior to the moment the car was built, nobody can prove it wasn't possible based on the assembly dates alone.

I also admit I'm basing my opinion on '64 data. There may very well be differences that would be found in a study of '69 EUNs vs. Time Built codes.

It also just occurred to me another factor, don't know if this applies to your car.

Van Nuys was hit by a strike in May. When they returned to production, they completed orders in progress but did not resume new production. That happened around early July.

So if your car was completed in July at Van Nuys, the engine in it was likely "old" as it sat in inventory until the strike ended.

The Time Built code however will show May so when you say a 6 month spread, not sure if you mean compared to the Invoice date or to the Data Plate Time Built code.

Point of this is to say that production disruptions at the final plant can affect the date spread. These disruptions aren't always obvious to many in the hobby.

The transfer of production in March from Lordstown to Norwood may also have created some anomalies.

But at least thru January, those factors were not yet in play.

No disagreement, just pointing out that there are lots of factors in play, relative rarity of certain engine codes is just one to consider.

Longer is possible for all sorts of reasons.

[Keith Seymore]

John - you missed one....

Originally Posted by jinxd68

I don't understand the EUN if someone can please explain how that works i'd appreciate it.

EUN = "engine unit number" (sometimes referred to as the MUN = "motor unit number").

All Pontiac engines were cast, machined and assembled in Pontiac Michigan. Near the end of each engine's completion, and before it left the engine plant, it was assigned a sequential identification number which was stamped on the block.

The EUN is shown on the protecto-plate and can be used to verify the original engine to that specific vehicle. The EUN is also captured in the PHS build information but it not always released to the public when purchasing a PHS packet.

K

[68bird400HO]

Just as a note, my 68 is a Lordstown car, ordered in late June with an 07C build date on the cowl tag. My block, heads, and intake are all dated early January. VIN matchs and the EUN also matches the billing sheet.

Another date code spread anomaly is with my 71 TA. It is a 12C Van Nuys car. Again is a vin #s match car with the block being the '70 455 carryover with May cast date. I have another 455HO motor out of another van nuys 71 TA built 400 units EARLIER than my car (probably a 12C or 12B build) and that car had an August cast block. There was a strike from Sept 70 to Nov 70 so that may have messed things up a bit.

[John V.]

Geez, '68! I knew that but confused my self.

Assuming 07C is a very late build, late year is when "build out" came into play. They would try to use up inventory.

As far as engine assemblies, I believe it was also a time when engines that had been "buried" in inventory finally came out of the back of the pile as inventories were drawn down. I bet a lot of earlier 400 HOs got built between the time that engine assembly was received at Lordstown and when your 'bird was built with those 'birds getting "newer" engines. I suspect your engine was one that had gotten buried. Finally it got pulled for your build, just luck of the draw.

Things started to get really squirrelly in the '70s as to block date codes. It's as if they purposely tried to install the engines in a random order. The VIN stamps really help at that point.

Keith, thanks for lending a hand, ha!

jinxd68, years ago I studied the heads on the '68 & '69 engines because there was a lot of misinformation floating around. I really don't remember everything I knew back then. Somewhere I have a copy of the Service Bulletin which identified the usage of the 061 head by '67 engine code and the head usage for the '68 engine codes. IIRC, even it contained some errors and/or was being misinterpreted.

But I don't recall any evidence that the 15 head was used on any '68 'bird engine.

You mention the exhaust manifolds. What are the p/ns?

Without continuing the word games, if the YT was known to get 16 heads and especially if you have no reason to believe the 15 heads were original to your engine, I would say it would definitely be more correct to put the 16 heads on the engine and L017 sounds like a reasonable date code.

Changing over an auto trans car to man trans, the only thing that would thwart you would be the PHS document since the '67 engines do not have a VIN stamp.

It is questionable whether this would raise the value. 4 spds tend to be in greater demand than auto trans so I suspect for a driver, it would be a plus. For a high end restoration, I'm not so sure.

Ask yourself why you would say "numbers matching" rather than describe exactly what you had done.

Rather than me answer your question about what you would call it, I'd recommend you reading the article I linked and judge for yourself.

[Greg Reid]

John V., as a point of interest, my '68 GTO (a very high production year by the way) has a 7 month spread between block/head casting dates and the build date.
The block and heads were cast in Oct/Nov.of '67. Build date is May '68.
VIN matches and is stamped on the framerail as well. EUN matches the billing history sheet.

[jinxd68]

The exhaust manifold codes are 9796992 dated J258 which i researched out as a 69 GTO according to Wallace racing. The other is 9796155 dated J168 which from same source was 69 Firebird. I am, according to story i was told when i bought the car, was i was the third owner. Car was in a garage from 82 until i purchased it from a salvage yard in 2000. Car was never "salvaged" as the yard felt it was to nice and old to part out. Car was resprayed blue but still retains all date code correct side bird glass and HG steel wheels and wire spoke hubcaps and 3.08 open rear. My thinking on car was that somewhere along the line someone swapped the heads for lower compression and just by dumb luck got the dates right. I have never seen any 400 bird in 68 with the 15 code. The PHS says 16 also. When they did this they probably just threw on manifolds they found would work. Now the 4spd scenario i was making a hypothetical situation. This car is and will be as close as i can to factory original except for a few upgrades like the radio and tires (keeping the steel wheels though). This car has been a fun one to have for reference due to how original it is.

[The Boss]

Originally Posted by Greg Reid

John V., as a point of interest, my '68 GTO (a very high production year by the way) has a 7 month spread between block/head casting dates and the build date.
The block and heads were cast in Oct/Nov.of '67. Build date is May '68.
VIN matches and is stamped on the framerail as well. EUN matches the billing history sheet.

What plant Greg? I'm going to guess it wasn't the Pontiac, MI assembly plant.

[carbking]

About 40 years ago, at my first AACA meet, I was listening to bearded old-timers (about my current age, but without the beards) talking about "original" and "non-original".

One of the old-timers said to the other: "Well, in my opinion, if they replaced the air in the tires, its no longer original"!

With no offense meant to anyone, this thread has become comical. However, there are a lot of really good points made. My opinion, for what its worth, is it is all about the money.

I currently have 1 mostly original (the oil, belts, tires, fuel, camshaft [the original failed], etc. have been changed); and 2 that are certainly not original (customized to my tastes).

Yall have a nice day!

Jon.

[John V.]

Jon, good points.

Greg, just to rule out a restamp, you would also want to confirm that the EUN is correct for a November assembled engine. Since the EUN is on the PHS doc, that makes it easy to restamp matching numbers. But there will be a big difference between an EUN from November and an EUN from later. May assembled '68 engines will mostly have EUNs around 700000. A November assembled '68 engine will be around 300000 or lower.

I have no doubt that such a spread is possible, just pointing out that there is another way to corroborate the evidence.

Unless you are talking about a Ram Air motor? I believe the special block and head castings used for it were infrequently cast. So assembly could happen well after the parts were cast.

A 350 HO isn't nearly so special.

jinxd68, 9796992 is a RH log manifold. It was first used for '69 but it was used for the 'bird as well as all other Pontiacs. It was a design WITHOUT the RH manifold mounted Heat Riser Valve.

The problematic HRV was eliminated late in the '68 Model Year.

This is another topic I researched years ago and forget details. I have the PMD announcement around here somewhere announcing the late year elimination of the HRV. (except for engines with HO manifolds).

Prior to that running change, the RH manifold was 9779328 which included the HRV.

After the change, I believe the standard log manifold was 9794320. It may have gotten some usage into '69 but the much more common '69 RH manifold was the 9796992.

The 9796155 is a center outlet LH log manifold that was commonly used on '69 big Pontiacs and '69 'birds.

My notes show that 9777756 was also used for the '69 bird.

It had been used in prior years, although the other common LH center outlet log manifold was 9779033 during those years.

It was never clear to me why two different p/ns existed (9777756 and 9779033) although one possibility was that they were cast with different iron at different foundries, allowing for an alternate vendor.

And while my notes say 9796155 was the more common one for '69 'bird engines, wouldn't surprise me if either of the other 2 versions were also used on some '69 'bird engines.

Since the later manifolds did have cast date codes, it should be possible to date match them to the engine assembly.

You might be right about the heads being date matched by dumb luck. But '68 was a tough year with the emissions changes. PMD produced the early heads (16 included) with a cast in A.I.R. rail, obvious evidence that they considered the possibility they were going to need A.I.R. After the success with the new open chambers in reducing emissions, they were able to avoid A.I.R. and after a couple months, removed the A.I.R. rail from the head castings.

It might also be that the early YT was intentionally assembled with 15 heads. Or maybe an assembler made a mistake. Afterall, there were big Pontiac 4 bbl 400 codes that were spec'd with the 15 heads.

The 15 heads were small valve but they had nearly the same chamber volume as the 16, so compression was barely different. Hard to imagine anybody going to all that trouble to swap heads for the negligible compression difference they would have made.

Could be somebody snagged the "better" 16 heads while car sat and the 15 heads were swapped in to make it "whole" again. But the likelihood of having the dates match just defies logic for me. Any evidence to show the heads were ever removed?

I guess the swapped out exhaust manifolds indicate something was going on. Hard to know all these years later.

[Greg Reid]

Boss, it's an Arlington car.
John, the EUN is in the 88000 range.
It's a base model auto with very few options. The original owner had this car until he died in his 80s in the early 2000s. The guy I bought it from was an aquaintance of the guy's mechaning. He was a Chevy guy who thought the EUN was the number to look at, so he told me it was a non original engine. I went underneath and found the partial VIN.