Hi
Having been lucky enough to own a Skyline, and some other beasties, I have driven at over 185 mph more than a few times, both on a track and on the autobahn.
I am just curious to know what you want out of this experience, is it purely to ascertain your cars maximum speed or the thrill of speeding?
I am not being judgemental, I would just like to impart some experience on this matter. Depending on your car ( you dont say what it is ) I will assume its quite modern and will reach 150+ in relative safety.
And that's the problem, modern cars dont have the same exhilaration as older cars used to, the first time I went over 130 was in a ford capri with an unlimited ellard turbo which to this day is the scariest thing I have ever driven, proper mental and you really had to concentrate on driving all the time, as one mistake and it would fishtail before you knew it, with no second chances!
I also had a legend of a Starlet Gt with 225bhp some 10 years ago again you really had to drive the thing because of torque steer and wheelspin, so you would think that my Skyline with stupid BHP would be the best thing ever, but its not.....it accelerates and brakes in a straight line goes well over 175 but so safely I have never ever had a moments doubt about anything it is so solid a car.
My point is, you can drive your car to the maximum and see white lines disappear very quickly (really boring after a couple of miles ) but once you have done it then what? a) get caught and lose your licence and even face jail nowadays or possibly lose control and suffer untold circumstances or b) go to a track where you can really let rip and have more fun than a bag of fun things on a fun day its the corners and other stuff that give you a sense of excitement like no other, legally.
Whatever you decide, just do it as safely as possible for you and others and enjoy !