I am sure that everybody had seen spoilers on cars but I saw a spoiler in the bed of a pickup that was big enough to be a tail from a small plane,it could been the tail from a plane but look like a spoiler

 

I saw one on an old pickup made of 2 x 4 uprights with a plywood wing (unpainted). My opinion of it is not important if the owner likes it ..... his truck to do what he wants.

 

dino , you are right about [ his truck to do what he wanted] got another question ,at what speed do spoilers help 20-35, 35-50, above 50- , what effects do the wind had on spoilers,I talking about winds that will push a pickup off of the highway when driving 50 mph

 

The speed that spoilers start to effect things is highly dependent on the design of the wing. Is it a true wing (airfoil) or just a chunk of something stuck up there to deflect the air? What angle of attack is it? etc.

The thing a lot of people don't realize is that wings are a double-edged sword. Properly designed they will give you more downforce for better traction, but that comes at the expense of creating extra drag.

 

Excellent post! Alas, many wings (blings) sold to the ricers (sorry, that is what they call themselves) are generally for decoration and have zero wind tunnel testing. Yes, there are companies that make real, usable and tested wings for cars. Agree it all depends on the wing's span, angle of attack, etc. Aero and Fluid dynamics is not my forte so please don;t ask me for technical details. The basics are more angle of attack produced more downforce AND more drag = lower speeds in a straight BUT GAINS in cornering ability. Formula 1 enthusiasts are familiar with the delicate balance of time gained via more wing versus more speed is the straights. Choose your 'poison.'




In the car i use for SCCA races (pic), have different diffusers and wings (front and rear) for low downforce tracks and high downforce tracks. Of course the wings provide adjustments for angle of attack and have winglets above the main front wing to dial in more or less as needed while the rear has a secondary span....

This brings up the vehicle's weight and aero downforce balance. A rear wing might help yet how is the front? What is your goal/intention for improvement?

Ok, will stop here as am really getting off the mark.

Here is a good basic design imo for a car in a sane price range http://www.aprperformance.com/index....d=47&Itemid=44

 

good info. but pickup trucks is not mention on the
web site, will a spoiler that is mounted above the
truck bed help to control fish-tail? what height above
the cab would be best for a spoiler ? do wind
deflecters on semi trucks function as a spoiler ?

 

The wings on the top of the cabs that you'll see here and there are to deflect the oncoming air upward to make it flow over the trailer instead of into the front of it. Anywhere else on the truck is for decoration.


So, if the wing's main purpose is to cause down force for better traction and control.......................what good is it ever gonna do on a front wheel drive vehicle when on the rear?


I have my personal opinion on it- if ya aint racin ***** to the wall at high speeds(for the vehicle) leave the crap on the shelf and save your money for a better vehicle.

 

that is a good point but how many 2 wheel drive pickups do you see that is front-wheel drive

 

I think they are just plain silly, but concede that it is the owner's prerogative to do as they please with their vehicle.

 

Excellent posts. Agree a wing for the back, as mounted on the rear of the bed, needs to be designed for street use and so this means a large main span and secondary upper span that will probably need to be angled a high degree to achieve a decent amount of downforce at 50mph on up. Of course this would also cause high(ish) drag, thereby lowering gas mileage and forcing the engine to work harder to achieve the same speed sans wing.

As for what height, you want the wing to be in the maximum airflow and the further back (behind the plane of the rear axle) the better due to leverage. So the further back you can go the less angle of attack and drag would be needed for the same downforce if the wing was more forward. Of course the wing mounting SHOULD be connected to the FRAME of the truck if you want to do it right.

ag30265 make a great point about a rear wing being... well... pretty much pointless for normal street use. Above the cab like we see on 18-wheelers is another story and great for deflection to reduce drag. This is why my Cargopro enclosed trailer has a V-nose AND ALSO an incline on the V section to reduce wind drag (see Cargopro website for pics).

Like bling, spinners, and neon lights, ckal704 is right in that it is his truck and if he wants mud flaps with silhouette of naked women, Yosemite Sam, or a sticker of Calvin pi$$ing on a Chevy emblem so be it. Still shake my head at pure street guys who raise their trucks up high, as this means higher center of gravity and increases the possibility of roll over (then they add huge tires that kill the towing abilility...). But hey, some people love that Big Bad Truck look and there is a multi-million dollar industry that serves their desires. Some people love Fords, others love their Chevys.. and the wheel turns round and round.

 

[QUOTE=enjoythetrack]Excellent post! Alas, many wings (blings) sold to the ricers (sorry, that is what they call themselves) are generally for decoration and have zero wind tunnel testing.=QUOTE]

i will never understand when i see one of those japmobiles rolling along with a spoiler mounted on the decklid, and yet the car is FWD, so any downforce obtained by the wing would actually raise the front of the car and hurt traction... i tryed to explain this to a kid with a honda at a car show once and he had no concept as to what i was talking about.

now if you want a damn effective spoiler, check out 1969 Dodge Daytona, or 1970 Plymouth Superbird.

took hundreds of man hours in the windtunnel to devellop those cars. (did i ever mention my other hobby besides ford trucks is musclecars...)

 

Some spoilers, such as the one that came with my wife's '04 Taurus SES is decoration only.

 

Well the thing you're missing is that traction doesn't just apply to the forward motion. In the case of a FWD car, depending on how it's setup, a rear wing would be used to gain more traction on the rear wheels for cornering. We used to race a VW Rabbit on a road course and the backend would always try to come around on hard corners (Over-steer). a little extra traction in the back would have been helpful.

Now, you're right though, for 90% of the "ricers" and the street drags, a rear wing on a FWD is just stupid and is actually hurting you.

 

good point, i could see that being useful on a road course

 

[QUOTE=godblessmud]I'll bet that Superbird wing doesn't do much of anything under 100 mph. Good place to set your beer down onto during cruise night (while parked).