It wouldn't surprise me that it makes between 400 and 450 HP and more torque than HP at the flywheel, the rear wheel HP and torque will be influence greatly by the converter loss and drive train friction loss
It wont come remotely close to 450. Would bet any amount of money on that.
I would guess 380- 385 ish
How much money are you willing to loose?
I've made 430 HP with all NHRA legal parts twenty years ago on two different 1971 340 motors with two different pairs of iron stock J and X heads
If I can do that so can most other engine builders with similar parts
The OP has a lot better parts and more C.I. to start with, hence my guestimate
The last pump gas stroker 340 motor I did in SO CA made 525 HP with a mild set of race W2 iron heads with 9.4 to 1 compression using CA 91 octane pump swill, the new Eddy 340 aluminum heads are better than those heads where
