Cam boy roulette
For gains this amazing, it must cost an arm and a leg right?!?
Well, the beauty of swapping in a new cam is the hp/dollar ratio.
As long as you pick a cam close to what might fit you (i.e.For cars that need to stay stock sounding and driving, but still want a kick in the pants for horsepower, something between a 214 and 220'ish duration would probably be best.For the majority of the cars out there, anything in the 221-227 range is probably a better selection, and for the guys that want all they can get 228 duration cam shafts are generally the minimum.The more extreme the lobe, the noisier your valvetrain will be and the harder it is on your valve springs...however, a more extreme lobe will generally idle better than a less extreme lobe with the same duration at 50 thousandths.
If your cam has very aggressive lobes and your cam lift is up there, I'd suggest you try to lighten your valvetrain by getting titanium retainers if possible.
Finally, the last number is the Lobe Separation Angle.