I just picked up what i told was a 403 from an 80 pontiac, but not quite sure it isnt a 350, it is painted blue not gold or black. it has 3x heads on it but i dont know how to identify what cubic inch motor i have. does anyone know where i can find the i.d. numbers at and what they mean? any help would be appreciated.
olds small block identification?
- Thread starter mastersativa
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Some blocks, before 1977, have their ID cast above the right hand center freeze plug, eg. D for 425, F for 455. Olds didn't cast the displacement into the side of the blocks until they went to the light weight design in 1977. The 1977 and newer blocks will have the cubic inches cast in large raised numbers right above the right hand center freeze plug, eg. 403. The 307 will be in liters (5L), and a diesel engine will have the letters "DX" on it. The engine VIN letter will also be cast into the side of the block. Note that the 260 blocks sometimed have the last 3 digits of the casting number cast there, "355", which is rather misleading
Found at: http://www.442.com/oldsfaq/ofblk.htm
Found at: http://www.442.com/oldsfaq/ofblk.htm
thanks, i was looking it over and found the numbers where you said, it has 350 cast on it, and they are 3a heads not 3x lol. which heads are better? my 307 has 5a heads on it, i would imagine these are worse than the 350s, correct? thanks again
mastersativa said:
The 3A heads were used on the 1977-1980 Olds 350 motors, though they COULD have been bolted to a 403. The block casting number is located on the small "shelf" above the water pump, next to the oil fill tube. Frequently you need to scrape all the crud away to read it. A 1968-76 350 block is 395558. The 1977-1980 350 is 557752. The 403 is 557265. I'm betting it's the newer 350.
yeah from what i can tell it is a 350. the block has 350 above the freeze plugs on the side of the block. the numbers on it are 557752, so i am pretty sure it is a 79 olds 350, because what i am finding is that 77-80 blocks have the 55772 casting numbers but 79 is with the 3a code and the others are 3b code. thanks for all the help you guys are great.
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