No VIN on factory installed block?
 

Hi, I was wondering if anyone here had ever found a factory installed motor from the early 70s without a partial VIN stamped in the usual location? I am trying to help a friend determine if his motor is the born with unit. Thanks for your help.

Only time I've seen that is with a SR (Service Replacement block). Are you looking in the correct location(s)? Most common area is along the side of the timing cover about halfway down between the top and bottom of it on the passenger side. Another location is toward the top of the timing cover farther toward the outside of the block

I should have mentioned it doesn’t have an SR # either. It does have casting and date numbers, the two letter engine code and EUN(?) number, just no VIN.

I believe the EUN number is on PHS paperwork, if you have that.

We've seen three different STILL INSTALLED engine blocks with no VIN.........
 

First one was a 428/370hp in a 1969 Grand Prix that we bought from the original owner. It was rusted beyond belief and we parted it out. This was in about 1985 - before GPs became somewhat collectible.

Second was a couple years later and was a 1971 GTO 400 engine that came out of a rolled and burnt GTO that we found in a wrecking yard in Tooele Utah. We bought the engine and transmission, then resold the engine about a year later. I think we still have the T400 somewhere.

Third one was a 455 in a 1973 Bonneville that was owned by a friend here in Las Vega$. We helped him change out the timing chain shortly after he bought it from somewhere back east. He drove it around for about three or four years and then sold it to someone out in California.

All of these had EUNS and correct matching date codes and engine codes. Just no partial VIN anywhere at all on the front surface.

Maybe we were just lucky enough to go through enough Pontiacs to stumble across these. I've gotta believe that there are/were more.

The EUN wasn't on the PHS starting in either 1969 or 1970.
 

I think that they stopped putting the EUN on the billing sheets in 1968 or 1969.

Quite possible this car's engine has one of them -- no VIN on it -- but dang oh so period correct and all. Not like 455HO blocks grow on trees. Never say never is what I say


https://bringatrailer.com/listing/19...ird-formula-2/

If the car was built at the California Fremont Plant (Z in the VIN) the partial stamp may be high on the engine block.
https://forums.maxperformanceinc.com...d.php?t=736578

Some blocks may have partial vin over below passenger head on front of block .

Recently bought 69 GTO WT 400 with vin stamped there . Atlanta plant car .

Some later Trans Ams were stamped there also.

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Some engines did not get stamped with a VIN......I've run into that a couple of times.

There is an older thread that is much longer that goes into this. I had a 1971 YE 455HO with EUN, but there was no VIN stamped into the block. It had been vatted and was totally clean, not even a trace where one was stamped. I believe the explanation that someone gave was that if the engine failed during run-in, it was pulled off to the side and a different engine was installed off the manufacturing line. That line typically didn't stamp the VIN.

I have seen a total of three engines without VINs that I'm aware of. One was the 1971 YE 455HO, another was a 1970 YZ Ram III, and the third was a 1970 Grand Prix 455 XF code. There may have been more because I rarely looked at VINs on the block.

I want to say that on the YZ block, I became curious because the engine was much later than the cowl tag. When I went looking for the VIN, I couldn't find it.

Yes stopped after 68

If you can disclose more exact data
- the block casting date and the block code and the EUN stamped above the 2 digit code
- the last 7 digits of car VIN , and Body Date from Trim Tag
I can check those parameters against the data base and let you know if it is possibly original to the car.


If its a 73 Catalina , its just an anomaly .
If its a GTO or Trans Am - it will come under deep scrutiny

Yes, I’ve seen it more than a few times late 60s and early 70s not common, but it did happen

I remember reading somewhere that the 455HO motors were “hand fitted” at the factory. I can imagine other high performance engines having the same treatment, but I am only speculating. So, maybe its possible that during the extra attention the stamping was overlooked. Also, I have a friend who worked in the Fremont, Ca. factory, his father before him, who tells stories of things that didn’t go the way they were supposed to, to put it mildly.

All Pontiac engines were cast , machined , stamped , assembled , test run momentarily on a propane fixture - at PMD in Michigan.

Then shipped by rail cars to the various plants.
The various plants stamped only the VIN's on the engines.

I recently sold a Van Nuys built '70 Trans Am that did not have a vin on the block. Engine appeared original to the car. All dates.. etc lined up with everything else. I applied muriatic acid to the area and nothing surfaced.

I am very suspicious of them, as i've seen plenty with very faded stamps, multiple attempted stamps (pic attached), machined faces that hindered the stamp, but I really haven't come across a block that has no stamp at all on 70's Firebirds.

A friend was sold a "bandit" '77 4-speed T/A and was told it had a numbers matching block. There was no stamp at all on the face by the water pump, but there was the EUN. The date and cast codes showed it was impossible to be numbers matching, as it was the 418988* cast block, not a 500577. Upon further investigation, it was determined the face of that block had been machined down in the past for a rebuild, and the motor had been replaced decades ago.

Canadian "PHS" (Vintage Vehicle Services )documents show EUN after 68.

I am not sure how to reply, but I have had four different VVS packets;
None had the EUN listed.
Maybe you have some inside knowledge which might permit me to confirm this?

VVS / GM of Canada reports have had EUN listed on 1970 models .
Never seen one for 1969 Pontiac. So I wouldn't know.

Inquired to an owner of a 71 TA sold new in Canada this week , his VVS did not list EUN .

Edit -
All the 1970 reports I have seen have been for GTO or Judge.
Can't say for certain if have ever seen one for an Fbody 1970.

Don't know why, this one is listed...
https://forums.maxperformanceinc.com...d.php?t=833860

In that thread , the 70 Judge lists EUN
The 70 Formula does not.
Owch , what a letdown
Shame on Norwood , maybe that's why the 71 TA from Canada did not list it either.

although this may be resolved;
the three I have here are all for 1970 Firebirds (2x Formula, 1x Trans Am).
The fourth one I gave with the car when I gave the car back to my brother.

I should have quantified my statement by saying that VVS documents I have held in my hands showed an EUN. This is a very small sampling (maybe 5). All were GTOs. Don't recall the years but if I had to guess I'd say 69 to 71. Don't recall the assembly plants either.

I was incorrect to assume that all VSS documents show an EUN. My apologies for the confusion. You learn something every day.

I have copies that seem to have the eun not shown on later copies.
That is the early copies had them, but at some point in time they dropped them. Also the dealers have been dropped a lot of time.


:confused:

Johnta1, on the versions you have without EUN , are any of them 70 GTO/Judge ?
If they have started omitting the EUN from those - then there is definitely something to make a fuss about.

BVZ, I may have been wrong.
:eek:


I looked at a few and they had the eun.
I may have been thinking of the sheets from Canada that were not Canada built? (had Baltimore, Pontiac, etc VIN or imported basically)


Example:

Except this one:

I really cannot remember for sure now ...
Was thinking they had EUN on all their 70 A-body Reports in the past.
Regardless of build plant.

However now , I'm thinking it was just if it was an Oshawa plant car.
Probably more logical .
If all my files weren't still trapped I could confirm that , pfft

Believe we might all be due for a refresher course on GM of Canada documents.

I did start a thread in 70-73 Bird section to see if anyone has Canadian docs for any Bird that shows an EUN on the docs.

Might have to do one in Judge section too.

It’s the 71 T/A selling now on BaT.

It’s the 71 T/A selling now on BaT.

Hope he and the high bidder can work out a deal on it.