There is a lot that should goes in to your cam selection. For instance what will the vehicle be used for, what operating RPM range will be, other mods done, and one of the biggest will be if it needs a converter or not. If you look at the cam details for instance shown on Texas Speeds and Performance website. They list for instance if it needs a converter. Once you put a cam in a vehicle that requires a stall and you DO NOT put a stall in the vehicle it will run bad. If you have a bigger cam that requires a stall and do not put in a stall it will want to push through the brakes. It will also feel weak down low as most of these bigger cams operate at higher up RPM's. It can have issues idling correct as well. When selecting a cam make sure you pay attention to the details. If you are unsure talk with your tuner before spending money a cam.
When you buy a camshaft for your automatic car or truck please look with your recommended parts. When it calls for dual springs for 600+ lift and 3600+ stall to work correctly they are speaking about the drivability of this camshaft. When your changing the camshaft to something 20-30 degrees of duration more then stock you will need a stall converter to operate correctly