hye, im new here

im driving neo 1.6 auto & now thinking to install hi cam but not sure whether its a good idea or not since i heard auto car shudn't install hi cam or else ur car will face so many probs after that
if installing hi cam is a good idea, what degree shud i use?

i need opinion from u guys who knows best & have experience with it

if u ask me y im thinking to install hi cam?
i want my car to be fast

what i already did :

- full exhaust sys
- cam pulleys...