How to tell if I have the L48 or L82 engine?

If you can decode the vin i think it should tell you .

Also, I believe the L82 had an L82 badge on the hood; L48s did not.

if the 5th number in your vin number is a L it is a L48 i belive it is a R four the L82 i have a 77 with the L48 my self

The 5th character on your vin will determine engine type. J for L48 and T for L82.

So I got a 73 impala thats swapped with the 75 corvette engine how would i tell which one it is

Look at the valve covers if there baby blue its a l48 l82 had fin then check the stamp code below the pass side valve cover the 5th diget is L its a l48.