If a head cam car with lid and cutout after dual magnaflow cats make 405rwhp then would the following get at least 420rwhp?

Ported throttle body=5-8 rwhp +
electric cut out before relocated single cat in the I pipe= 8-10rwhp + underdrive pulley 4-5rwhp
180 degree stat.

I'm totalling 422 to 428. Does this sound right.

 

yes, it should hit about 420.