# how to determine original engine



## gijoe (Apr 17, 2011)

I'm new to GTO's, replaced my 66 vette with a 65 GTO 4 spd convertible. The man I bought car from was not original owner and did not know if engine was original. Car build date is 4th week July, 65, engine build date is D 2 5, I believe April 2nd 65, engine code is WS 349540 and engine cast number 9778729. The car matches the PHS data but since there is no vin on 64-65 GTO's how would one determine if it is original to the car? Thanks, Joe


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## geeteeohguy (Feb 2, 2008)

You should order the PHS (Pontiac Historical Society) paperwork on the car. The PHS will include the build sheet with the options the car came with. It will tell you the engine code for the car, but not the EUN (Engine Unit Number). If you find that the PHS states that your car should have a WS coded engine, all is well. The only way I know of to verify if the car has its "born with" engine still in place is to have a copy of the Protect-O-Plate, which has the engine code and EUN stamped on it. I have the POP for my own '65.....which shows my original WS block to be long gone! Good luck, have fun, and welcome aboard.


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## gijoe (Apr 17, 2011)

I have the PHS paperwork, the paperwork calls for the WS code 389 tripower which is what is in the car. The intake manifold is correct sacting number and the tranny is the a correctly cast 3885010 muncie with a build date of May 12,65. No POP.


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## Thumpin455 (Feb 17, 2010)

Did the 65 engines have the VIN stamp near the front cover? That would make it easy to tell.


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## geeteeohguy (Feb 2, 2008)

No VIN stamped on engines until the '68 model year, unfortunately. Gijoe, it sounds like you have the "correct" engine in your car. Unless you have the POP, it will be impossible to determine if it was there from day one. If I were you, I'd be pretty happy!


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## gijoe (Apr 17, 2011)

I love this car, it has way more power than my 327 vette had and even more than my 409 Chevy!


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## geeteeohguy (Feb 2, 2008)

Gijoe, that's the thing about Pontiacs that most folks don't know....they're super powerful and fast. You have to drive one to appreciate it, and once you do, you're glad you did. I like all classic and musclecars, but there's a good reason I drive GTO's!!


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## 68greengoat (Sep 15, 2005)

I'm with GTOguy, it sounds like you have the correct engine. The casting number you provided is for a '65 GTO with a tri-power. You have the tri-power, date code is right along with the correct casting number and engine code. On my PHS, it does list the engine unit number. If you can find that number in your doc and it matches the engine, you're golden...


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## gijoe (Apr 17, 2011)

where on the PHS documets does it list the EUN?


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## geeteeohguy (Feb 2, 2008)

GI, The EUN is not listed on the PHS documents for a '65. The ONLY place I know of where you'd find it is on the POP.


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## 68greengoat (Sep 15, 2005)

My mistake. I thought all PHS had for the most part the same info. I was quoting from a piece of doc that showed the vin, invoice#, date, invoice amount, trans#, option codes, EUN, zone, dealer#.... etc. Also says "Car Billing History" on it.


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