Asked the same ? @ the morgue a few months back and got some interesting responses. It is in the general viper discussion area around the 1st of June, but here are a few:
John, I just put the #'s in my spread sheet and came up with two figures: With the hard top I remember RT/10's have a CD of about .45 and with top off a CD of .50.
For a CD of .45 you will need approximately 624 RWHP to go 200 MPH.(Hard top on)
For a CD of .50 you will need approximately 684 RWHP to go 200 MPH. Top off
Compare this to a GTS needing "Only" 514 RWHP to do the same 200 MPH.
I would agree you would need some aerodynamic modifications to be stable. I remember being in an RT/10 once going 170+ and it felt nothing like the stability the GTS has at 190+. You would also have to check your wheel bearings, have brand new tires that are Y-Rated, have a high speed alignment and maybe add some rake to your car to add to the downforce proportionally. Heffner and myself are planning to do some closed track high speed testing. If you wanted to attend, I am sure I could give you a 200+ MPH ride if you filled out all the necessary waivers.........LOL!
Assuming that drag forces are proportional to velocity squared, Drag is governed by the ricotti equation,
-m d/dt (v) = CA v^2
where m is the mass of the car, v is the speed and
CA is the drag coefficient
The drag coefficient is then
CA = (V2 - V1) * m / (V2 * V1 * t)
Say the mass is 3000 pounds giving
CA not CD = 0.56 (well say you have an RT with the top off and a fat girl in the passenger seat)
The power (HP) required to overcome drag is given by
HP = CA v^3.
Mike, I think the cd for a GTS is around .38, but not sure. This was based on my RT with the top off.