I recently bought a 67 Impala convertible and it happens to have a mystery engine. I was wondering where the serial number is located so i can confirm what it is. It is supposedly a 1970 GM 305, not to sure on that though. I know they are located at various points, but i would prefer if there was one without major dis assembly. Any help is appreciated, Willis

 

passenger side front of the block just under the hed mating surface is a ledge with the id numbers stamped on it .

 

thanks so much

 

the number stamped there is the actual serial number which would correspond to the vin number if the car had numbers matching. It would be more useful to look on the drivers side back there is a small flat spot where there is what the call the "cast number" cast into the block this will tell you approximately when it was manufactured.
Heres a websit to help http://www.mortec.com/castnum.htm