1965 Buick 225

in 1965, the Electra could have had either a 401 or 425.

http://www.teambuick.com/reference/years/65/65_engine_number.php



GM vins didn't code specific engines until 1972, so that isn't much help for your question:
4 8? 37 5 H I 62091
4 = Buick
8? = digit missing, '82' would be an Electra, '84' would be an Electra Custom
37 = 2dr hardtop coupe
5 = 1965
H = Flint, MI
I = should be a "1", not the letter i
62091 = sequential production number, should be six digits
 
65 225 engine

I have a 1965 Buick 225 which I'm trying to find out what engine came in it everything is original vin # is 48375HI62091 can any help me

There are two letters stamped in the top of the block in front of the valley cover, it will be LT (401) LW (425 single carb) or LX (2 carb) forget about the numbers, look for the letters. It may not have the original engine but still should be a 401 or 425.. FYI the air cleaner with 445 is a 401 and the 465 is a 425.. Those are torque numbers.
 
I didn't find those numbers but it was a writing on the engine that said engine with a arrow pointing to the # 5H162091 can you find out what those # mean
 
engine ID

H would mean the block is a 61, that is not and easy swap into a 65.. The 61 block is a one year only, it had a different oil pump that only works on a rear sump pan, your car has a center sump oil pan and oil pump with a different bolt pattern. It is possible to drill a hole in the block and bolt a 62-66 oil pump on a 61 block and use the 66 oil pan.. The next problem would be the crank, the 61 had a crank for a dynaflow trans, yours is the ST400 so either the crank was modified correctly or incorrectly or the later crank installed. What is the block casting number, it is on the bell housing flange.
 
The engine is a 1965 not a 1961. 5H162091 is the engine number which matches the last 8 digits of the VIN. This means it is the original numbers matching engine. It decodes just like the VIN, as shown above:

484395H162091

4 = Buick
84 = Electra 225 Custom
39 = 4-door hardtop sedan
5 = 1965
H = built at Flint, MI
162091 = sequential production number, range was 100,001 to 343,884 for Flint built cars excluding the Riviera and Wildcat.

Look on the engine in the same spot you found the number 5H162091, but on the passenger side not the driver side to find the production code. This shows where:

http://www.teambuick.com/forums/view.php?pg=indent_engine_where

1965 reference section:

http://www.teambuick.com/reference/years/65.php
 
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There must be two letters on the top of the block you are not telling me about, they are on the passenger side top of the block, near the vin number you gave me. Those two letters maybe stamped upside down or not even next to each other. FYI anyone can stamp a different vin # on a block. call me 530-272-1564.. Russ
 
Yes, anyone can restamp the VIN. They could also restamp the production code or change the air cleaner sticker. However, 5H162091 is not a valid 1961 VIN or production code.
 
block ID

We have built over a 100 nailheads, maybe closer to 150, last year we built 20, every one of the 57-66 engines have numbers and letters stamped on them, the second digit in the vin stamp is a letter and tells you the year except the 65 model, for some reason they used H again, I have a 65 425 with an H .. The 64 we have in the shop has a K , my 65 401 in my roadster is also an H so that was my mistake. 95% of the time I go by the other letter stamps to the passenger side and yours will be an LT (401) or LW (425).. I am sure you have the original engine, the question you asked was which engine, the std 401 or optional 425, is that correct? There is also a lump behind the drivers side on the bell housing flange that only the 425's have. The block casting on all the 425's end in 704 although people claim the "705" block is a 401-425 I have sonic tested them and that rumor is false..
 
The difference is that the VIN number format for 1954-1964 is 9 digits and for 1957-1964 all 9 digits were stamped on the engine. VIN number format for 1965-1980 was 13 digits and only the last 8 of the VIN were stamped on the engine. The 1965 VIN format uses a number for the model year and a letter for the plant code while the 1954-1964 VIN format uses a letter for the model year and a number for the plant code.
 
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Ok, that makes sense, I am still learning and every now and then new info .. But the question still is what are the other two letters on this engine so it can be ID?
 
My manifold

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1965 Buick 225
 
Steven 1196914 is the head casting number, which indicates 1959-1966 364-401/425 (not very precise). Attached is the type of picture we need. In the attached photo the stamped engine production code is LR (visible just behind the thermostat housing), we need to find out the same letters on your engine.


Nailhead casting numbers:
http://www.teambuick.com/reference/casting_numbers_nailhead.php
 

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What can I do to give me more horse power with out really messing with the original engine cause it's already pretty fast I'm just a speed head any suggestions
 
Lr??

That is really strange, the LR is a 65 Gran Sport 400 (401) the only other time the R was used was on the 66 Gran Sport and the 62-63 Two barrel LeSabre.
 
hopping up the nailhead

What can I do to give me more horse power with out really messing with the original engine cause it's already pretty fast I'm just a speed head any suggestions

I have all kinds of free tech info on building and modifying these engines in my website.. nailheadbuick.com
 
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