i didn't even know they madce a 405... i thought 404 was their largest.
for a street application, i'd say its too big.
b16s will give you about 11:1. with a huge cam, you're going to want more compression....
11:1 for 403's
12:1 for 404's
12.5:1 + for 405's
would be my best estimate for a good compression ratio for the cam