What is a 361 big Block ?

I have a '62 361 out in the yard. It still has its original 4 bbl intake and carb. The block is stamped HP. I guess that was the last year for hipo 361s. I've thought of installing it in my new '65 Coronet 440 wagon. It currently has a 318 2 bbl with a TF. It appears they can be made to run well. Would the Purple Stripe cam be a waste of money?