340 bored over 0.030 inch and stroked 4 inches

Ya it will be a 416 cid engine.
The hp is hard to guess with out all the details. One part can change the out come by 40hp.

Torque on the other hand is fairly easy most street or hot street engines are gonna be around 1.15-1.25 lbs-ft per cid so in your case 480-520. You can get more than that but where talking big heads, huge solid rollers, high cr and intake exhaust to handle it.

Hp on the other hand comes down to your heads and how much of the available cfm you are using. Again most street and hot street engines are gonna be 1.7-1.9 hp per cfm. So depending on your level of porting I'd say 425-475 hp. Depending on cam and combo.