Dont remove the flip over headlights. Its what makes a GT a GT.
Yes they do make you go faster if you are geared for it.Okay, if that's true, then if you go out on the highway and drive at 80mph with the headlights down, then flip them up, you should detect a speed decrease. I assure that you will not. Your speedo needle won't budge a mm. Of far, far, more consequence and air drag is the massive mouth of our grills, bumpers, the pile of silverware sitting on our windshields that they call wipers, flat round side view mirrors, license plates, the big hollows in the wheel wells behind our wheels, etc.. Our headlights flipped down just look cool.....to some people.....but they don't make you go faster.
Ho Lee Chit!!! That widebody and modern tail light set up!!!! Where... How...??? Kieth??Just a suggestion, you may want to do a search for Eurotreffen. This is a large gathering of Opel GT's across the pond each year. Could be a source of inspiration, some of those shown are highly modified. This site does have some purist but for the most part understand a desire to create your own thing. I am not someone who would like a Lowrider but respect the work that goes into the Build. Also you may want to join the Opel Motorsport Club. The most recent issue of the club magazine shows an exploded view of t View attachment 430271 View attachment 430264 View attachment 430265 View attachment 430266 View attachment 430267 View attachment 430268 View attachment 430269
If you are talking about the Aqua and Black colored GT's. I think those are later model Fiberglass production GT's made by a company who's name starts with a K. Only sold in Europe.The only 2 that look good in Gordons pics are the blue one and the black one. The rest look like regular cars now.
Modern pickups actually have the same drag coefficient as our GT lol. The frontal area is much higher though. Almost double for most pickups. My same formula gives 158.95HP required for my Toyota Tacoma to reach 100mph which is about right.You're assuming that a straight wedge is the optimal shape for that part of a car. For all you know, the bow wave coming off the bumper may be causing a vortex to form and, like a spoiler, the headlights up disrupts the vortex. Using all your equations, a pickup truck shouldn't even be able to start rolling 'cuz it's dead flat to the wind. I've done the speed change test countless times and you don't notice any change. You can quote formulas all you want, but if you can't replicate their results by actually driving and performing the test, then they aren't 100% valid in this example. We can argue back and forth all we want, but only a wind tunnel test at the mild speed of 80mph will tell the tale.
YepIf you are talking about the Aqua and Black colored GT's. I think those are later model Fiberglass production GT's made by a company who's name starts with a K. Only sold in Europe.
They say that speed doubled requires HP squared. So it takes 4 times the power to go 200 mph for a given vehicle than it does to go 100 mph.Also remember that speed is an exponential factor in these equations. The HP required to maintain speed shoots up really fast above highway speed and beyond.
That is exactly true. The formula above confirms that since speed is squared.They say that speed doubled requires HP squared. So it takes 4 times the power to go 200 mph for a given vehicle than it does to go 100 mph.
Yes frontal area is a huge advantage for the GT. One of my aerodynamics books shows that, for example, that a first generation VW Scirocco has nearly the same CD as an Opel GT, even though their appearances are vastly different. But the frontal area is much greater on the VW. So for the same HP and gearing, the GT would have a higher top speed.
I would have sworn those were done by grafting GT sheetmetal onto a Miata....Yep
Did some Googling after I saw a note posted in the German Yahoo group about a KEINATH GT GT/R that was for sale in Germany. More photos: http://retractable.free.fr/uk/index.html http://www.ractif.com/~cpittet/voitures/_g_z/keinath_gt_r/ Some details: Horst Keinath first repaired Opels and...www.opelgt.com
Cubed, IIRC. (Force is squared, power is cubed because it includes velocity).They say that speed doubled requires HP squared.
8x.So it takes 4 times the power to go 200 mph for a given vehicle than it does to go 100 mph.
I think, technically no. It goes up as cubic, not an exponential.Knorm65 said:Also remember that speed is an exponential factor in these equations.
Fair, could a mod split the topic into "GT Aerodynamics"? Even just this much is kind of cluttery to a build thread. :/Folks, great discussion but respect this is Witness's GT build thread so careful not to hijack it. Suggest a new thread on aero effects of headlights and modifications.