I have a bit of a newbie quesiton I suppose. I was wondering how exactly aftermarket camshafts would creat more horespower. Correct me if I'm wrong, but the camshafts are put into motion via the crank through belts, chains, vvt, etc...Once the camshafts are in rotational motion, the 'nubs' open and close the intake and exhaust valves allowing for internal combustion to take place. So, how exactly would aftermarket cams increase hp? The only thing that I would assume is that there are more 'nubs' and/or they are placed at more aggressive angles so that the intake valves can squeeze in a little more air/fuel mix...I'm not really sure...Just want to be correctly educated on the issue.

 

Not really an expert or anything but the way I always thought it worked was aftermarket cams have different shaped lobes enabling the valves to stay open longer, allowing more fuel/air in.



Here's the article

http://auto.howstuffworks.com/camshaft.htm

 

http://auto.howstuffworks.com/camshaft.htm

 

You will see aftermarket cams list features such as "valve lift" and "duration" both key to more HP/TQ