DOHC has the ability to retard/advance separately to create a certain desired powerband - oily ek9 made a good point. If you do NOT know what the limit is for valve to valve contact, be aware that they may hit.
we've had decent success with settings like +2 intake and -1 exhaust..but it really varies between motors and ecu remapping overall. Cam gears are usually adjusted last after the AFR is safely tuned and monitored on the dyno and then cleaned up once more once the desired powerband (via cam gears) is achieved.