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Technical Big Block 396 ID Help

Discussion in 'The Hokey Ass Message Board' started by freeflynstl, Apr 9, 2017.

  1. freeflynstl
    Joined: Jul 16, 2009
    Posts: 278

    freeflynstl
    Member

    My dad has been trying to liquidate some of his 50 plus years of hot rod hoarding. He's retired, lives on a fixed income and could use the money for other things. I told him I'd help him try and sell some of it. One of the items is a big block 396 that came from a 69 Chevelle SS396 4-speed car. I've identified the following numbers from it.

    Block - 3955272
    Heads - 3964291

    Using the resources I have the heads look like the L78 heads but other than that I'm at a loss. I don't know much about Chevy big blocks but I'd like to get him a fair price for the motor. It was running in a 28 Plymouth about 4 years ago and I pulled it from the car and sat it in the corner of the shop. I've kept it turned over every few months and now he needs a little scratch.

    Can anyone help me ID the motor or tell me where to look and what to look for to tell if it is indeed a real 375 horse L78 from a Chevelle?

    Any help would be appreciated.

    Thanks in advance,

    Andy from STL


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  2. Black Panther
    Joined: Jan 6, 2010
    Posts: 1,767

    Black Panther
    Member
    from SoCal

    Andy...anything stamped on the front pad? Tell us what the casting dates are on the heads and block. Should look like this A169...that is January 16th of 1969.
    Might be able to tell if the stuff has always been together by the dates. If it is a 375 HP motor...it'll be a 4 bolt main...hope that helps..
     
  3. freeflynstl
    Joined: Jul 16, 2009
    Posts: 278

    freeflynstl
    Member

    I've had the pan off. It's a 4bolt main. I'll have to get over there and pipe the valve covers off.


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  4. mgtstumpy
    Joined: Jul 20, 2006
    Posts: 8,839

    mgtstumpy
    Member

    3955272
    1969 396 or 402. 265, 325, 350 or 375hp 2&4 bolt

    3964291
    1969-70 396 or 402 375hp L-78, Intake Port 325cc
    427 425 or 435hp L-71/L-72
    454 Closed 450hp LS-6, 108.0c

    You need the suffix code numbers stamped on the engine pad to specifically identify what it came from
     

  5. squirrel
    Joined: Sep 23, 2004
    Posts: 49,315

    squirrel
    Member

    It's probably a 1969 375 hp engine. It should be worth a bit.

    The stamped numbers will tell.

    btw I sold a pair of those heads for about a grand a few years ago.
     
  6. Black Panther
    Joined: Jan 6, 2010
    Posts: 1,767

    Black Panther
    Member
    from SoCal

    Andy..almost by definition...if it is a 4 bolt main...it was a L78 motor....375 HP. Knowing the dates would confirm that and show whether the parts have been together since day one. Check the front pad for stampings....unless it's been decked during a rebuild...
     
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  7. freeflynstl
    Joined: Jul 16, 2009
    Posts: 278

    freeflynstl
    Member

    Just getting back to where I can look at this motor some more. Looks like the front pad stamping reads:

    T0625JD
    If my resources are right that was built June 25th in Tonawanda and Is from a 69 Chevelle 375HP.

    Serial number is too hard to make out. I can make out s few numbers but is the VIN portion. The first three digits I can't make out and those are prob the most important. Looks like

    353136

    As for the heads and their casting date I can't find squat. Just the previously mentioned number and the words HI-Perf and what looks like I9 a dot then another 9. If u red it upside down they'd look like 6s. Picture attached.

    Any other help is appreciated. Thanks for the help.

    Andy from STL


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  8. squirrel
    Joined: Sep 23, 2004
    Posts: 49,315

    squirrel
    Member

    I 9 9 is Sept 9th, 1969.

    neat!
     
  9. freeflynstl
    Joined: Jul 16, 2009
    Posts: 278

    freeflynstl
    Member

    So I assume that's mystery solved. 69 Chevelle L78 396 375HP. Next question would be what's a fair price for this motor. Does not have original intake. Does have Mallory dist and fuel pump. Edelebrock water pump, etc. mocked it up once in my Chevy II

    Like I said previously...was in a 28 Plymouth about 4 years ago. I rode in it, drove it. No smoke, no noise. Ran good and hard in that little coupe.


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  10. Black Panther
    Joined: Jan 6, 2010
    Posts: 1,767

    Black Panther
    Member
    from SoCal

    Andy..if the heads are I99....September 9th of 1969...then they aren't original to the shortblock...the shortblock was assembled June 25th. Make sure the dates you gave us are correct....the stamping where the JD code is might be T0825 or T0925....then the heads would be cast before the shortblock was assembled. As it stands...if your dates are correct...I'd split up the shortblock and the heads to maximize $$$...since they aren't original to each other...
     

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