What motor do i have?

[Thelittlecutlassthatcould]

So I've got an 87 cutlass supreme and i cant figure out what motor I've got. I have run the vin and it was built in pontiac michigan but didn't tell me the motor. It also has vortec heads which i know aren't factory so that has confused me more. Obviously if i looked at the casting number i would know right then what it was but i cant for the life of me get to it.

 

[pontiacgp]

if it is a 5.7 you'll find it on the ledge at the back of the engine, driver's side

 

[lilbowtie]

I'm assuming a SBC the casting # will be where pontiacgp said and to find the specifics of what it was born as you need to get the stamped numbers from the front of the block
just in front of the LB head