Geez. You made the statement that various addons to a truck would change the aerodynamics and possibly make the tailgate down reduce drage. Where is your proof on that? Fact is TBone, you completely took a wild guess with no basis.
Wind tunnel tests have been done on far more than just stock trucks. Tests have been done for effects of tonneau covers, campers, camper shells, and more. It's not proof you want. It's your defense to making statements that are just guesses.
Yep, that is exactly what it is and backed up be the numerous claims by many that dropping their tailgates improved mileage, despite your wind tunnel tests. Saying that simple wind tunnel tests of basically stock vehicles are the absolute answer is in a word, idiotic.
No matter how you spin it, wind tunnel tests are not real world and what happens in the perfect conditions of a wind tunnel are not what always happens in the real world and I doubt that they test these vehicles with non factory add-on like bug deflectors and rear mounted spare tires. But if you know that they do, please provide some links to these tests as I am curious as to the results and what exactly was tested.
People have claimed adding a tornado, magnets and other gizmos have increased their mpg as well. Think they really did? Doubtful. People will find what they are looking for.
BULL. Are you aware that new airplane designs are completely tested on computer models and partial structural wind tunnel testing? If they don't represent the real world then how the heck do they test new airplanes such as the new A380 that flew its first flight without trouble....after scores of wind tunnel testing to prove its airworthiness. Wind tunnels tests certainly can and do prove a vehicles drag coefficient.
While a wind tunnel can be used to calculate some drag, it cann work as accurately as it does for a aircraft because aircfat only suffers from aerodynamic drag anf lift losses while a car has more varible in the overall formula. Also a aircrafts motion is always into the wind as to relative motion once it is airborne (if in a cross wind it will drift with it and adjust course for it) while a vehicle can experiaince wind drag for all angles and some of which may produce increased drag vs pure frontal air flow.
----------------- The SnoMan
Who says wind tunnel testing on cars is only done from pure frontal air flow?
I am sure than in some of these cases, these things did work. The tornado has a valid design and if an intake system is not well designed, the vortex it creates could improve intake efficiency and cause an increase in HP and mileage. Will it happen in every vehicle, of course not but to say it will never happen is just being ignorant. Many of these gizmos will work in very specific situations and the builders of them try and make it look like it will work for all situations which is of course complete BS.
So what? Are you really comparing an airplane to a truck. That is one hell of a reach and completely incorrect. An airplane is always in the direct flow of air or it would fall out of the sky and most people who are still alive don't add things to the aircraft that will significantly change the aerodynamics of the aircraft. BTW, the computer models do most of that testing.
LOL, more like scores of computer model testing and again, an aircraft deals with airflow in a MUCH different mannor than a ground based vehicle. Ground based vehicles can drive through jet wash, shear winds, and turbulance with little more effect than being shaken a little. Can the same be said for your aircraft?
Sure it can and I never said anything different but then again, that is in line with the airflow, not counting turbulence, crosswinds, or changes to the airflow over the vehicle due to customer add-ons.
Hmm...how many cars has the tornado been proved effective at increasing mpg? I know of only ones that it has been proved ineffective. Know any examples with credible testing?
Those customer add-ons have been tested for their effects in wind tunnel testing.
LOL, I am far from an expert in airflow but with the infinite possibilities that the customer can come up with to alter the airflow from that of when the truck was built, it is silly to make a statement that the tailgate up will ALWAYS do better.
situations,
Nope, but then again, I have no desire to purchase one so why would I bother?
And you can prove this how and what exactly were they tested for? A bug for deflector for example is tested to make sure is creates enough airflow to keep the bugs off of the window and they could care less about if it would effect mileage with regards to the position of the tailgate. The same can probably be said for anything. The wind tunnel tests done on them, if any, are done to make sure that they will hold up and not cause the vehicle to become uncontrollable, not mileage with regards to the tailgate position.
Show me a test that shows a truck will do better with it down.
Roy
What complete bull. Wind Tunnels tests are routinely done on vehicles to measure drag coefficients along with a host of other issues. It depends on the market the manufacture is aiming for as to which issue is of more importance than another for a particular vehicle.
Yes, they are as they come from the factory, not with every consu,er add-on available and if you think they do, show me some.
On this we agree and the manufacturer of a bug deflector has a primary concern of keeping bugs off of the window, not mileage with regards to the tailgate and I doubt any wind tunnel tests are done at all for a rear mounted spare tire carrier or a roll bar.
Nope, don't have to.
I guess if that is your answer.....
IIRC, there was one done with a 94-02 Ram that showed it did better with the gate up.
What aftermarket items and modifications were done to the trucks? I already said that in most if not all cases, that a bone stock truck will do better with the tailgate up but not all trucks remain this way.
Screw Ford, *I* would like to see 20 MPG out of my V10.. :)
you can just shut the engine off and coast *grin*
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