49 roadmaster, help identyfing engine

Hello. Im restoring 49 roadmaster with str8 fireball with dynaflow gearbox. i have problem with displacement of engine.

engine no. 1828965-3

 

my bad.

 

By the numbers and the location of the dipstick, it looks like it is a 1949 320 cu. in. out of a series 70, so it might well be the correct one for your Roadmaster.

 

I found it here.
https://www.buicks.net/shop/reference/engine_ident_52.php

Having played with a few of those engines, and having owned one or two, this leads me to believe it's a 320, they were usually painted black from the factory right after the war, it could be a factory or warranty replacement, I don't know.
Now I know immediately after the war the smaller engine (248) was offered in Super and eventually in Special. The Roadmaster was the only one that got the 320. According to the Buick books I have, the Super always got the smaller engine throughout the straight 8 era. It was only in 1953 that Super got the larger V-8 while the Special had to make do with the 263 straight 8.

Checking the "Standard Catalog for American Cars, 4th Edition ", (Gunnel, Krause publications, 2002) (OK, so it's a bit old, but so am I) it states that engine numbers 5220972-7 to 5548366-7 were used in Series 70 Roadmaster in 1949. This one reads 5322745-7 so that puts it squarely in the middle of the 1949 run.

The first number you were looking at was a casting number from the foundry. The second number (5322745-7) is the serial number. Count up the digits and it makes sense.

 

You're misreading the numbers. Count the digits; - there are 8 depicted there. Seven are the individual serial and the last one is the series number.

The bottom picture with the number starting 1828965-3 is a casting number. There were a number of blocks that would have this number on them.
The stamped number on the flat plate is an engraved serial number. There are seven characters in the number followed by "7". The book has it written as "-7" because all the engines in that series had a "7" in them. So the last individual number in this is a "5", not "7" and since there isn't enough room on the plate they omitted the dash.

My 46 Super had the "5" at the end of it's number and also didn't have the dash.

The serial number for the car was attached to the frame rail and on the body on the inside of the driver's side door pillar. The engine numbers were always stamped on the flat plate. The casting numbers were put on at the foundry and have nothing to do with the car's ID number. It corresponds more with the part number if anything. If you had a listing of the casting numbers you could theoretically date the block down to a shift, but I think that information is gone.

The car serial number and the engine number were different. Unless you had the actual build sheet, there is no telling exactly which block was in there from the factory, what most experts do is date the car using the data plate and if the engine serial is within an acceptable or plausible range it's considered "correct", unless of course you have the actual information.

This block is a 320 cu. in. and it belongs in a Roadmaster and it falls within the 1949 model range.