First off, the police can not "take your car or license". They can only cite you and it is the courts to decree confiscation of the vehicle or suspension of license upon conviction. Legally, in a 65 mph zone, if you are going 66 the LEO can pull you over and issue a citation. A reckless driving stop, i.e., 20+ over the posted speed limit, will probably result in arrest and likely subsequent suspension of driving priviledges.
So, never go over the speed limit and you'll always be in good stead with the LEOs. The other road users that don't abide by that creed may not be too happy with you, though.
There are other reasons you can go to jail, besides speeding. For example, burning rubber at a green light can be called reckless driving or exhibition of speed and in some cities it's not a ticket but jail.
I found out first hand some years back. Picked up a Ducati 999 and the ignorant bug bit me bad. 147 MPH in a 70, excessive accelleration, wreckless driving and something else. Would have been fine if I wouldn't have ran out of gas. Needless to say, the bike was impouned, I was impounded and I almost lost my license. Let's see, $600 for lawyer, $225 to get bike back and my $550 bond fee.
In California, travelling in excess of 100 MPH, exhibition of speed, reckless driving (3 moving violations), speed contest (racing), and driving wrong way on a divided highway are just some of the offenses which are misdemeanors, and are arrestable violations and your vehicle would be impounded, and your license can be suspended.
Uh, you're in Colorado. Everyone speeds here. True that 20+ is most likely going to cause issues. Most local or CSP won't pull you over for under 5MPH over. I try not to push it though.
Last week I was driving up I-25 and the overhead annuciator board read (something like) "75mph means 75mph - no exceptions". Majority of the traffic was doing about 80 at the time. I guess they can only pull over those they can catch up with.