[TRADERMIKE 2012]

See:The list That I provided " 1967 " Pontiac engine production!" Note: that the last 4 428 ci are HO and have "special equipment" , the 4 above them are 428 ci with " special equipment" but they are not HO. Why?

Note: All are 4bbl.

Thus: If Y-Branch Exhaust is the "special equipment" then what makes the 428 ci an HO? I can speculate , there is that word again, the first 4 in the list are 2 bolt mains and the last 4 are 4 bolt mains. All blocks were prepped for 4 bolt mains but not all got drilled for 4 bolt mains? Let me know the answer to this one too.

[TRADERMIKE 2012]

Originally Posted by steve25

Ok, I’am out !
I am not reading thru all of this!

MIKES ANSWER TO THIS :Come on back after you have slept and try Microsoft Edge it reads back to you , I find it helpful after reading other people long ass posts. Big atta- boy to the one with the answers to what I seek.

[grandam1979]

This will help you out,

[Baron Von Zeppelin]

Those additional stampings are from a rebuilder/machine shop.
Not factory stampings or any type of installation data.
Have had numerous virgin 67 428 engines in the past, no such stampings on them.
I sold used Pontiac parts full time in 80's - mid 90's and specialized in HiPo Pontiac engines mainly.
Shipped them all across the USA.

It has obviously been apart and rebuilt before.
They even painted it the wrong color when they rebuilt it, and then more recently someone has resprayed it the correct color.
So its virgin authenticity left a long time ago.

Engine isnt factory paint, or factory timing chain/gears, the cam in question was probably used in the rebuild. The Tripower could have hopped onto it at any point between 1967 and last week.
People were even putting TriPower on 69-70 Judges back in the days.

67 car production would have started around early Sept 1966
Your April 67 engine is way on past anything that would entertain an early orphan that might have squeezed in between the non-multi-carburetor edict.
538897 means that 538,896 V8 blocks were cast before yours for the 1967 production year. The date and the math throw that speculation down the drain.

All 1967 and 1968 428 engines were 4 Bolt Main Cap
The 428 HO got a better air cleaner and better exhaust manifolds
The HO was not standard in any 67 Pontiac
428 was only standard in a 2+2 for 1967 - and that was the 360hp

Numerous various items get penned as "special equipment" on order forms.
Sometimes engines, sometimes transmissions, sometimes axles.
They were usually mechanical items that were not standard equipment for the masses of general production.
Don't get hung up on special equipment as listed on an order form.

Special Equipment only becomes more noteworthy when it shows up as a memo on a buildsheet or a 9D memo on an invoice.
Those are items that are not on the order forms at all.

You have a great engine, but it seems like you might be trying to overthink some parts of its history. Engines get rebuilt and upgraded all the time over the course of 54 years. Some have been rebuilt several times in that timespan.

A couple years ago a guy on here found a 67 4door Catalina 428 HO with front disc brakes.
Untouched virgin in so-so condition. Ultra-Rarity / OddBall 100% complete and running.
He took the engine and parted the car out.
So add 4door Cat to the list of prospects of where the engine might have came from.
Any full-size 2door, 4door, Wagon or Convt could have been ordered with 428 HO

[TRADERMIKE 2012]

Originally Posted by grandam1979

This will help you out,

Mikes ans: Good find , years ago I came across this info. but It is lost in my archives and you saved me from looking for it. Thank you very much, I too have a wealth of Pontiac information to share with the forum and will give it up as we go.

[TRADERMIKE 2012]

Originally Posted by Baron Von Zeppelin

Those additional stamping's are from a re-builder / machine shop.
Not factory stamping's or any type of installation data.
Have had numerous virgin 67 428 engines in the past, no such stamping's on them.
I sold used Pontiac parts full time in 80's - mid 90's and specialized in Hi Po Pontiac engines mainly.
Shipped them all across the USA.

It has obviously been apart and rebuilt before.
They even painted it the wrong color when they rebuilt it, and then more recently someone has re-sprayed it the correct color.
So its virgin authenticity left a long time ago.

Engine isn't factory paint, or factory timing chain/gears, the cam in question was probably used in the rebuild. The Tri-power could have hopped onto it at any point between 1967 and last week.
People were even putting Tri-Power on 69-70 Judges back in the days.

67 car production would have started around early Sept 1966
Your April 67 engine is way on past anything that would entertain an early orphan that might have squeezed in between the non-multi-carburetor edict.
538897 means that 538,896 V8 blocks were cast before yours for the 1967 production year. The date and the math throw that speculation down the drain.

All 1967 and 1968 428 engines were 4 Bolt Main Cap
The 428 HO got a better air cleaner and better exhaust manifolds
The HO was not standard in any 67 Pontiac
428 was only standard in a 2+2 for 1967 - and that was the 360 hp

Numerous various items get penned as "special equipment" on order forms.
Sometimes engines, sometimes transmissions, sometimes axles.
They were usually mechanical items that were not standard equipment for the masses of general production.
Don't get hung up on special equipment as listed on an order form.

Special Equipment only becomes more noteworthy when it shows up as a memo on a build sheet or a 9D memo on an invoice.
Those are items that are not on the order forms at all.

You have a great engine, but it seems like you might be trying to overthink some parts of its history. Engines get rebuilt and upgraded all the time over the course of 54 years. Some have been rebuilt several times in that time span.

A couple years ago a guy on here found a 67 4door Catalina 428 HO with front disc brakes.
Untouched virgin in so-so condition. Ultra-Rarity / Odd Ball 100% complete and running.
He took the engine and parted the car out.
So add 4 door Cat to the list of prospects of where the engine might have came from.
Any full-size 2 door, 4 door, Wagon or Convt. could have been ordered with 428 HO

MIKE ANSWER TO THIS : Thank you for your input, if all is true then my search is over . You can't make a silk purse out of a sower's ear , now can you?

[tekuhn]

Originally Posted by TRADERMIKE 2012

MIKE ANSWER TO THIS : Thank you for your input, if all is true then my search is over . You can't make a silk purse out of a sower's ear , now can you?

You have far from a "sows ear". You possess the highest horsepower engine that Pontiac produced in 1967. Unfortunately, there's no reason to believe that the '66 tri-power, or the late '50's camshaft were installed by the factory. Pontiac did not stamp dates of installation on engine blocks.

I say enjoy your engine and be proud of what you have. It's still a rare piece that anyone would love to have. I certainly would.

[TRADERMIKE 2012]

Question came up in my mind," what did say Royal Pontiac stamp on the 428 ci motors that they installed in Pontiac Firebirds and GTO'S to make them into Royal Pontiac's and how did they stamp the upgraded motors for this up grade". Please, true answers from anyone who truly has the information I seek? My 428 ci motor is stamped upside down under the passenger side head with 2288. I am told from forum members that this is a date a mechanic installed the Tri-power carbs. and #524886 Tri-power cam in a vehicle. Someone must have one of the Royal Pontiac upgrade YK 428 ci HO engines Installed in there Royal Pontiac." Is your motor stamped like mine in the same place and upside down and Did any dealership like Motion in Baldwin Long Island or Dana in Cal. do this to there upgrades?"

[Tom Vaught]

You need to PM Keith Seymore. He uses his real name on the board.

Keith's dad campaigned a 64 GTO and a 65 GTO under the Royal Banner in Royal Oak Michigan. Keith obviously has been around the Royal Dealership for many years and his Fathers car's would have the engines stamped as you say IF that stamping info was correct. I have my doubts about that story.

He should be posting here again once he finishes Racing this coming week-end.

Tom V.

[tom s]

58 years or so ago!Chasing windmills.Tom

[TRADERMIKE 2012]

Originally Posted by tom s

58 years or so ago!Chasing windmills.Tom

Mikes answer to this , I still would like to learn if Royal Pontiac stamped there blocks in this way because they installed 428 ci blocks as an up grade into there vehicles using crate engines from the factory. Shot in the wind -Yes- but if a forum is for conversation lets talk.

[TRADERMIKE 2012]

Originally Posted by Tom Vaught

You need to PM Keith Seymore. He uses his real name on the board.

Keith's dad campaigned a 64 GTO and a 65 GTO under the Royal Banner in Royal Oak Michigan. Keith obviously has been around the Royal Dealership for many years and his Fathers car's would have the engines stamped as you say IF that stamping info was correct. I have my doubts about that story.

He should be posting here again once he finishes Racing this coming week-end.

Tom V.

I am speculating this is not a factual Question.There are only 1045 428 ci YK HO blocks ever produced in 1967 despite the half a million engines produced in 1967 total prier to mine . Lets see were this quest goes.The story is this motor was used in Moon shinning in the Carolina's and went off the road being chased while installed in a truck and latter retrieved and sold to the man I bought my car from. Perhaps that moon shiner is on your forum . This engine has 1966 Tri-power Rochester carbs. and a # 524886 cam and the YK EUN # is 538897 check your records please. The #2288 is "Not" factory looking stamped upside down in the upper passenger side of the block directly under the Head. The letter " P" running from side to side on the Head and is factory stamped under the upside down #2288 also . What is the meaning of that letter "P"? Nobody has come up with that answer yet.The man I bought this 1979 Pontiac Trans Am from is dead now and his name is Randy Minic ,perhaps some one remembers selling him this 1967 428 ci HO motor, the vehicle was Randy's with a 403 Olds.

[tekuhn]

I have no information about whether and how Royal might have stamped engines they transplanted or modified in customer vehicles, but I did have an engine that was blueprinted by George DeLorean’s Leader Automotive which was the continuation of Royal’s high performance service department. They did stamp the block in the same location with the name LEADER and the service ticket number. Nothing else. I can’t say how Royal did it, but might have been similar.

[TRADERMIKE 2012]

GOOD INFO. THANK YOU, MIKE

[tekuhn]

Looking back through this thread, I'm not sure you have ever answered the question if the block is still standard bore (4.120"). Checking that could go a long way to determining if the engine has ever been in the hands of a machine shop. As several have stated, the most likely scenario is that the foreign stampings were placed there by a machine shop while the engine was being rebuilt. There is no standard for how a shop does this, but I assume it it mostly done to protect themselves so nobody tries to claim an engine has a problem that they never worked on. So far, nobody has come forward with any similar stampings on any of their engines to support this being the work of some mysterious special order team within Pontiac, or from Royal Pontiac either. If the modifications were made by a dealer, it seems much more likely to have happened in the part of the country where the car/engine was originally sold.

Bottom line, unless you can find another person with a block similarly marked who knows who made those markings and what they represent, you will never know what they mean. Any shade tree mechanic could have installed the tri-power and cam, and it happens all the time.

[TRADERMIKE 2012]

We have one Motor Block photo that shows a shop will stamp the Engine Block after they work on the Block . Lets see were the trail ends up. Not that my Motor is special but I want to see more Block Stamps to compare mine to . When we find the upside down Stamp in the same place as mine we may have a clue to who performed the work on my Engine. Perhaps I don't find a match but it's worth a try. By the way I have never removed the Heads off this motor, I can believe she has 10.75:1 CR from the factory . My roommate said "the man I bought the vehicle from changed the upper Head gasket when he replaced the timing Gear and chain, the Head Gasket looked to fresh to be 50 years old". The man I bought the vehicle from said "the motor is stock". However, how stock is the question? We already know the cam and Tri-power is "not" stock. I myself installed Johnson Lifters and 16 Chromemolly HD Push Rods. This is the second new Timing gear set, with more adjustment then the first one.The first set only had 7,000 miles on it when I just replaced it. I installed the "041" cam after the original Cam proved faulty. Then we added Air Induction. So you can say this Engine has a light build on it. I added a new Oil Pump and Oil Pan too. Under the Valve Covers I added the Oil Drip Rails,a stock part plus the new 7/16" Screw in Studs with Nuts and Washers. I use MSD Ignition and Headers. Tri-power carbs. are Rebuilt and up jetted. New Power Piston and Power Valve. Filter Screens in the carb. Bowl area . I added discharge tube Anti- Peculation vented device with holes and AC vent Valve in the carbs . I forget the the exact names of them. The bottom end is strong with the 4 bolt mains and when we changed the Oil Pan the Stock Crank was Armor- steel. Since I have not removed the Heads I would not know if the Exhaust valve Seats were replaced. When I replaced the old warn out Cam I found a cracked nut on # 1 rocker arm Stud. I bent 2 push Rods, one after the other, while Testing and Tuning before I Found out why the stock push rods were bending at 130 miles per hour. We are painting the Engine , Engine compartment ,Trans.,Gear Vendors and under the Body . We also Painted the Brake Calipers and Wheel Wells. I have to install the Wire loom and finish the Engine compartment Electrical wiring Professionally. We have the new rear Brake lines and a Proportioning valve on its way. Soon I will install the new Torque Converter.We are replacing carb. Gaskets and I am thinking how to finish the Tri-power Carbs . It seems that just keeping up with this project as I drive it keeps me from finishing the project. I have all the Options available installed on this vehicle but the Cruise Control. Even that is painted and ready to be installed ,some day, if I ever get there. Then there is the wish list. Michael out.

[TRADERMIKE 2012]

Mike here , I recently found in the 1961 Pontiac shop Manual General Information section this: Engine Serial number and Engine code on Right hand upper Block. Motor Vehicle Identification number right hand front Block about half way down and that is were my side ways "P" is . What doe's "P" mean? This is what I red : " The MFG Vehicle Identification # is located on a machined pad on the front of the right hand bank of the block.The production Engine # is used for production control purposes during MFG. So my MVI # is a letter not a number on my 1967 428 ci Block and that adds to the confusion.Plus the letter "P" is stamped side to side ?

[mgarblik]

Originally Posted by TRADERMIKE 2012

The 428 HO motors with a 4 speed behind them also had a special valve spring package. ANS: to this: Mine is automatic PC code TH 400. YK means automatic 4bbl most of the time or so I have red. I have dual springs 670 D -port Heads. . How do the manual vs auto springs differ? ANS. 2 Pontiac did not make the Corrvette nor the Corvair so I have no idea what your taking about with that other then it's true that Chevy with the 427 motor kept the tripower thing going thru 1969. GM stopped all Divisions in 1967 from using Tri-power so I red.Called an "edict".

When GM issued an "Edict", Pontiac, unlike Chevrolet, Oldsmobile and to some extent, Buick, followed the rules. Chevrolet completely ignored them, and it seems Oldsmobile was generally slow to respond. An example would be the Oldsmobile 3x2 barrel engines they ran through 1967 and the Chevy stuff through 1969.

[tekuhn]

Attached are two pictures showing the block pad of my 1961 engine. The area near the intake has the block code and the production number. The area near the exhaust has additional stampings that I don’t know if they’re factory or something else. I will say that this engine HAS been rebuilt by a machine shop prior to my purchase. You will notice a P stamped there. It doesn’t line up very well with the numbers and might well have been stamped at a different time. There is nothing special about this engine, except they left half the cylinders off. .

[Tom Vaught]

Numbers in the second picture were not from the factory.
Number in the first picture was. Not sure about the large Letters Stamp
in second picture. Most times those letters are about the same size as the numbers stamp.

Tom V.