eng size

[thisismylife]

I have a 1981 sierra that im trying to figure out what eng it has I now it is a v8 but not sure what one any way of telling them apart thanks

[2000CAYukon]

You need to get the casting number off the block. See this page for locations and engine sizes based on casting numbers: http://www.mortec.com/location.htm

//2000CAYukon

[alexquade]

umm, i have a 1994 gmc, i was told from one person it has a 350 in it. but i found out later it has a 305 in it. my mom also had a 1983 chevy scottsdale, it had a 305 in it.