The notchback did not get "extended B pillars" nor are fastbacks the only Fieros that ever had spoilers. Actually read the thread if you want quantifiable evidence. It's been presented multiple times:
As you can see, very small reduction in CD can make some quite important benefits to the fuel economy of the vehicle. The "stability" I mentioned, is perhaps a little confusing. I wasn't talking about down force, but the spoiler does help stabilize some air flow at the rear of the vehicle, which reduces the CD, which in turn does help stabilize the vehicle a tiny bit. None of this is going to make any noticeable difference in stop and go city traffic, no, but it does help at speeds in excess of 45 MPH (aka highway speeds).
The weight loss from the spoiler only is going to make no difference at all. What does it weigh? 5lbs? One's body weight can fluctuate that much throughout the day. You'll get that 0.01 CD back, and your car won't accelerate any faster.
Tell you what. Drive your Fiero as you normally would for one week and note the MPG. Now remove the spoiler and repeat the previous weeks driving habits as close as you can. While this wont be a perfect "test", I can pretty much guarantee you wont notice jack monkey squat of a difference. Wanna bet?
GM should hire you to solve all their aerodynamics needs. Your overwhelming superior knowledge of fluid weights and viscosities is vastly greater than all the wind tunnel testing they pay for.
Well what he says is accurate, so whats the problem ? We all know lots of crap automotive engineers design is worthless. ie/ who thinks plastic door handles were a good idea ? Who thinks having to disassemble a whole front of a car to change a light bulb was smart ?
You asked for quantifiable data and Dobey gave it. You want the sources of the data? I listed it for my post. You want the source for the data that Tinkrr posted? It's here: Road & Track Nov '84
quote
Originally posted by BV MotorSports: You should note the claimed reduction in cd was due to the combination of the extension of the B pillars and rear spoiler. As to the extent of how much each change affected the overall cd, I'm betting it was primarily the B pillars.
You would lose the bet. According to Car & Driver Feb '86, the drop from Cd 0.35 to 0.34 was the difference between a fastback without the wing vs one with the wing.
quote
Originally posted by BV MotorSports: So I will say it again, the rear spoiler does jack monkey squat. There is NOTHING to be gained as it relates to vehicle stability, economy etc with the addition of the factory spoiler.
You can believe whatever you want, and but the specs don't lie. The wing does have a positive effect.
Originally posted by rogergarrison: Well what he says is accurate, so whats the problem ? We all know lots of crap automotive engineers design is worthless. ie/ who thinks plastic door handles were a good idea ? Who thinks having to disassemble a whole front of a car to change a light bulb was smart ?
What he said is not accurate at all. It's a statement of complete ignorance about how air flows around and through the Fiero, and how the spoiler works.
What he said is not accurate at all. It's a statement of complete ignorance about how air flows around and through the Fiero, and how the spoiler works.
You want to cling to the belief that the stock spoiler has a "positive effect", "improves vehicle stability" and "increases MPG" thats one thing. The effects that you so diligently defend, while insulting your fellow forum members, (me specifically) is down right pathetic. You are going to set there and tell the members of PFF, and any visitor that stumbles across this thread, that the stock GT spoiler provides a MEASURABLE difference? BS!!! Hey you can believe what you want, but you will not insult me if I disagree.
Originally posted by BV MotorSports: You want to cling to the belief that the stock spoiler has a "positive effect", "improves vehicle stability" and "increases MPG" thats one thing. The effects that you so diligently defend, while insulting your fellow forum members, (me specifically) is down right pathetic. You are going to set there and tell the members of PFF, and any visitor that stumbles across this thread, that the stock GT spoiler provides a MEASURABLE difference? BS!!! Hey you can believe what you want, but you will not insult me if I disagree.
/thread
It's not a belief. It's a proven fact. I am not clinging to anything. If you don't want a spoiler on your car then go rip it off. And I haven't insulted anyone. You are ignorant of how the spoiler works, and you refuse to look at the facts. I could have insulted you if I wanted to, but I didn't. I simply pointed out your ignorance, and pointed at the facts you keep ignoring.
You can disagree all you want. It doesn't make you correct. The facts very clearly show that you are wrong.
Also, you do not get to choose when a thread is done. If you want to stop commenting in a thread, that's fine. But just because you want to get the last word doesn't change any facts.
The facts are plain and simple. Reducing CD increases fuel economy and vehicle stability (this is only aerodynamic stability). The stock spoiler reduces CD. Therefore the stock spoiler increases fuel economy and vehicle stability. Yes, the change in CD is measurable (as evidenced by it being measured by multiple parties 30 years ago), as is the change in fuel economy (but very few people apparently know how to use the scientific method to test and measure such things).
If you just want to wax your ego, go to your room and lock the door first.
If you just want to wax your ego, go to your room and lock the door first.
And that means what, exactly? You and I both know what you elude to there... yeah, real "family friendly" there buddy. Lets see what Cliff thinks about that. If I were to judge by your ratings, I would say it is safe to assume you aren't one to hold your tongue and your peers have judged you as much. Talk about being blind to the facts. If you want to cling to this alledged .01%, go ahead. I don't drive in a controlled environment or wind tunnel. If you are too ignorant to acknowledge the fact that there is NO measurable real world effect on having that bit of GM decoration nailed to the back of a Fiero, that's your problem. Bury your head in the sand or come in here and thump your chest all ya want.
What would be in a list of things that the typical driver would notice affecting Fiero performance & handling?
Here's a start, in the order I would suggest: Engine Tires Suspension Alignment Brakes
I'm not sure the typical driver would detect any effect provided by 'measurably improved' aerodynamics. For example, I don't notice my '84SE being unstable with the up-force of the front fascia compared to my '88 Formula. Maybe I'm just not going fast enough...
I'm not sure the typical driver would detect any effect provided by 'measurably improved' aerodynamics. For example, I don't notice my '84SE being unstable with the up-force of the front fascia compared to my '88 Formula. Maybe I'm just not going fast enough...
David, you are absolutely correct of the above quote, people who don't push the upper limits won't notice anything that means much. However, those who do push the extremes realize the benefits of the aerodynamics. Case in point is that Pontiac wanted to campaign this car in racing, so they did the work to improve the aerodynamics to keep the car more stable. The main reason for the Aero Nose, is that when they were testing Fiero's without it, with higher horsepower engines at GM's Milford Provings, the cars almost flipped over backwards - at speeds above about 125 mph. That lead to very extensive Wind Tunnel testing for front fascia and development of spoilers.
The "OP" wanted to know if it makes a difference, he/or she didn't specify conditions. Ask anyone who runs their car really hard on a road course if they'd remove their aero nose, or spoilers !
[This message has been edited by California Kid (edited 01-17-2014).]
What he said is not accurate at all. It's a statement of complete ignorance about how air flows around and through the Fiero, and how the spoiler works.
I read BV Motorsports statement as wax your car so the water beads up, watch how water on it does during a drive. Ive seen the water set on the spoiler and when it moved at all , it went off the front edge. You only show your own ignorance. Test it for yourself. Id do it and post a video of it, but I dont have a winged Fiero on hand.
[This message has been edited by rogergarrison (edited 01-17-2014).]
Originally posted by BV MotorSports: And that means what, exactly? You and I both know what you elude to there... yeah, real "family friendly" there buddy. Lets see what Cliff thinks about that. If I were to judge by your ratings, I would say it is safe to assume you aren't one to hold your tongue and your peers have judged you as much. Talk about being blind to the facts. If you want to cling to this alledged .01%, go ahead. I don't drive in a controlled environment or wind tunnel. If you are too ignorant to acknowledge the fact that there is NO measurable real world effect on having that bit of GM decoration nailed to the back of a Fiero, that's your problem. Bury your head in the sand or come in here and thump your chest all ya want.
Who is the one insulting whom now?
If you are too ignorant to acknowledge the fact that external factors change your measurements, then that's your problem. Your willing your own ignorance has nothing to do with what the facts are. The facts are the difference is measurable, and has been measured by MULTIPLE parties. Those facts have been pointed to by multiple people in this thread. Your choice to ignore them is your problem. It doesn't make your wishful thinking correct.
The facts are there, and they are real. But your obvious emotional propensity can also affect the MPG you get by "measuring" at the pump. Weather also affects it. A lot of things affect it. But in the world of science, each of those effects must be measured separately. You cannot state that one of them has no effect, when all the others change arbitrarily, and you saw a number very similar to the last number you saw.
Originally posted by David Hambleton: What would be in a list of things that the typical driver would notice affecting Fiero performance & handling?
Typical humans only notice large and immediate changes. They can't think far enough ahead to consider how small changes can add up to large benefits further down the road.
Originally posted by rogergarrison: I read BV Motorsports statement as wax your car so the water beads up, watch how water on it does during a drive. Ive seen the water set on the spoiler and when it moved at all , it went off the front edge. You only show your own ignorance. Test it for yourself. Id do it and post a video of it, but I dont have a winged Fiero on hand.
His statement was "do this, and you'll notice the water stays on the wing, so therefore there is no effect."
He made an assumption by not understanding what is happening. That is ignorance. He is assuming that air must be interacting with all surfaces of the spoiler, and that the water beads aren't moving away by gravity or inertia.
And you seem to be making the same assumptions, based on what you think you see.
If anyone wants to see actual numbers and air flow visualizations of a fiero with and without a rear wing, find me a good 3d model preferably in Parasolid (.x_t) or something that can be opened in Solidworks.
Hmmm... water 'beads' on a well waxed car. I've noticed that after a brief rainfall, even at highway speeds the surface tension of water droplets 'sticks' them to most surfaces. I still have to wipe them off to avoid water spots. Even the windshield (subject maybe to the highest velocity of airflow) needs wipers.
Maybe if the car is thoroughly 'Rain-X' treated the path of the beads would show the airflow more readily.
Smoke seems to be the best indicator of airflow in a wind tunnel, since that's what's used.
First, lets settle up with the confusion everyone seems to have about spoilers being misidentified as air-foils.
A spoiler is designed to reshape the turbulent air coming from the rear of a vehicle to push it further back increasing the stability of the surrounding air flow. It will affect drag and improve mileage, although you won't notice the pennies you save unless it's over an extended test period. They are not, nor were they ever designed to improve down-force.
An air-foil is another matter entirely. It's shape produces noticeable high and low pressure zones that create lift. This isn't speculation or opinion, every plane that defies gravity does so using this principle. A proper air-foil mounted to a car is upside down compared to the shape of an airplane's wings, so it creates down force. The faster you go, the more force is created. Ever see a plane taxi down a runway? Now this doesn't include the tanning beds I see on most of the tuner cars, those tear drop shaped end caps do jack monkey squat.
RESULT: The spoiler on a Fiero will do "something" but it won't make it stick to the road any better. You can expect to save a few pennies at the pump if it's your daily driver over the course of a year or so of use.
To frick and frack : the term ignorant is really what you two are arguing about. Give the OP back his post and realize that you can't read the tone of someone's voice though a keyboard and that "Ignorant" is what you both have been by carrying on like you have been over a word that has multiple meanings.
[This message has been edited by eldervampire (edited 01-17-2014).]
When I picked up my 87 GT it had the spoiler (reference to what the OP called it) but had been taken off by the previous owner because one of the stantions had broken (probably caught it on something and pulled it.) I was so happy to be driving a Fiero again I didn't mind too much and drove it for several months without a spoiler. Since the car has been sitting for so long ALL the suspension's rubber bushing are pretty mushy as I can feel it going down the freeway. Not uncontrollable but the thing had a lot of roll back and forth even a little bit while accelerating - the thing flexes. So I'm driving it to work a couple of days a week, gathering various parts for the engine, suspension and so on and just rather preferred the aesthetics of a spoiler on a GT. Had it on my 85 GT and I enjoy just seeing it in the rearview mirror. I finally get a replacement stantion for the wing and put it on, very pleased with how it looks.
My surprise was how much it improved the stabilty of the Fiero. It still has slop but I would say there was maybe a 20-30 percent improvement on how well the Fiero drove on the freeway in a straight line. I'm still gathering parts to urethane the cradle and bushings but I was very impressed at the little bit that wing does. I bought my first Fiero in 1990 and have been involved with them and driving them pretty consistently since. I feel I know how an 84-87 is supposed to feel like.
My first Fiero was an 87 coupe without a wing and my Fieros West members can attest I didn't drive slow. The 85 GT was the first one I had with a wing and I wouldn't have said I could feel any difference handling wise from the view point of a wing. If it wasn't for the sloppy suspension of this 87 GT I doubt I would have felt any difference with or without the wing either. Like I said, I'm just in it for the looks.
BTW Witzenberg mentions in his book that the wing was the biggest in production at the time which I believe would have been true until the Supras came out with their Superbird like wings.
Photo of IMSA Coupe in Wind Tunnel, photo clearing shows the rear spoiler is not intended to take advantage of air coming off the roof, it is there to manage rear end air turbulence that comes up the back and moves forward onto deck lid on non-spoiler Fiero's.
Edit to add: While I don't have any photo's of it, both factory and IMSA spoilers manage air turbulence better to reduce rear end lift. This in effect does result in improved down force, as it reduces the amount of negative pressure across the rear deck lid creating the lift at high speed. The IMSA type does a little better job than Factory Spoiler because it closes out the air gap you see under the Factory spoiler. In my opinion GM didn't want to fill this gap on Production Cars with Spoiler, as it does increase vision blind spot, and it was easier to offer as an option with spoiler stanchions. So in general there are minor improvements to CD, Mileage, and Down Force Lift with both spoilers. Proof that they perform as described would be directly related to how well the Pontiac Racing Team did when competing these cars, if those spoilers didn't have any benefit, they sure as heck wouldn't have been on the cars they campaigned, as it's the little differences that separate the winners from the loser's.
Just had to give PIP a try.
[This message has been edited by California Kid (edited 01-18-2014).]
Photo of IMSA Coupe in Wind Tunnel, photo clearing shows the rear spoiler is not intended to take advantage of air coming off the roof, it is there to manage rear end air turbulence that comes up the back and moves forward onto deck lid on non-spoiler Fiero's.
Just had to give PIP a try.
Isn't that what I said?
quote
Originally posted by carbon:
From my reading the Fiero spoiler serves mostly to assist the detached air coming off the roof over the deck-lid, reducing drag by splicing the updraft from the rear surface with the air flowing over the top...
It's an easy thing to get confused about, as the spoiler works different than what most people expect it to do. That's why they spend a great deal of time in the Wind Tunnels to actually see what going on with smoke screens. There are plenty of dynamics going on, and as you increase speed they have a dramatic affect.
GM should hire you to solve all their aerodynamics needs. Your overwhelming superior knowledge of fluid weights and viscosities is vastly greater than all the wind tunnel testing they pay for.
It's an easy thing to get confused about, as the spoiler works different than what most people expect it to do. That's why they spend a great deal of time in the Wind Tunnels to actually see what going on with smoke screens. There are plenty of dynamics going on, and as you increase speed they have a dramatic affect.
When I picked up my 87 GT it had the spoiler (reference to what the OP called it) but had been taken off by the previous owner because one of the stantions had broken (probably caught it on something and pulled it.) I was so happy to be driving a Fiero again I didn't mind too much and drove it for several months without a spoiler. Since the car has been sitting for so long ALL the suspension's rubber bushing are pretty mushy as I can feel it going down the freeway. Not uncontrollable but the thing had a lot of roll back and forth even a little bit while accelerating - the thing flexes. So I'm driving it to work a couple of days a week, gathering various parts for the engine, suspension and so on and just rather preferred the aesthetics of a spoiler on a GT. Had it on my 85 GT and I enjoy just seeing it in the rearview mirror. I finally get a replacement stantion for the wing and put it on, very pleased with how it looks.
My surprise was how much it improved the stabilty of the Fiero. It still has slop but I would say there was maybe a 20-30 percent improvement on how well the Fiero drove on the freeway in a straight line. I'm still gathering parts to urethane the cradle and bushings but I was very impressed at the little bit that wing does. I bought my first Fiero in 1990 and have been involved with them and driving them pretty consistently since. I feel I know how an 84-87 is supposed to feel like.
My first Fiero was an 87 coupe without a wing and my Fieros West members can attest I didn't drive slow. The 85 GT was the first one I had with a wing and I wouldn't have said I could feel any difference handling wise from the view point of a wing. If it wasn't for the sloppy suspension of this 87 GT I doubt I would have felt any difference with or without the wing either. Like I said, I'm just in it for the looks.
BTW Witzenberg mentions in his book that the wing was the biggest in production at the time which I believe would have been true until the Supras came out with their Superbird like wings.
Thats what I call the ' clean effect '. You noticed it handling better because you wanted to. I name it that because have you ever noticed that your car runs better after you wash and polish it it. A clean, shiny car always runs better than a dull, dirty one. Its exactly what always comes to my mind when someone says my car handles so much better after I put a spoiler/ wing on it. You cant help but laugh. None of the factory parts have any effect driving a car at legal speeds. You wouldnt have any real difference in performance if you took off the whole front bumper cover and drove it. Even Super Birds and Daytonas dont have any difference you could feel at legal speeds. * you 'might' feel some side sway driving in very hard wind conditions over 50,60 mph like a truck, or bus would.
Originally posted by rogergarrison: Thats what I call the ' clean effect '. You noticed it handling better because you wanted to. I name it that because have you ever noticed that your car runs better after you wash and polish it it. A clean, shiny car always runs better than a dull, dirty one. Its exactly what always comes to my mind when someone says my car handles so much better after I put a spoiler/ wing on it. You cant help but laugh. None of the factory parts have any effect driving a car at legal speeds. You wouldnt have any real difference in performance if you took off the whole front bumper cover and drove it. Even Super Birds and Daytonas dont have any difference you could feel at legal speeds. * you 'might' feel some side sway driving in very hard wind conditions over 50,60 mph like a truck, or bus would.
And you have credible references to support your claims, I presume?
Yes. Drive any box truck, semi or motorhome on the freeway in 60 mph wind and you will find out. Ive driven Superbirds and Daytonas and you can feel the rear pushed sideways when a semi or bus passes you. Its not dangerously swaying, but def feelable. Its more extreme on my motorhome where you have to steer into it to keep going straight.
This wing is the biggest Ive ever seen on a street car and Ill even bet you dont feel much from it till your over 150 mph, if anything then. Its 6' x7'. Its on a 1987 Porsche Gembella slant-nose.
Yes. Drive any box truck, semi or motorhome on the freeway in 60 mph wind and you will find out. Ive driven Superbirds and Daytonas and you can feel the rear pushed sideways when a semi or bus passes you. Its not dangerously swaying, but def feelable. Its more extreme on my motorhome where you have to steer into it to keep going straight.
This wing is the biggest Ive ever seen on a street car and Ill even bet you dont feel much from it till your over 150 mph, if anything then. Its 6' x7'. Its on a 1987 Porsche Gembella slant-nose.
LOL. So, no, of course you don't have any credible references to point to. You only have poor assumptions from the experience of driving. Any car is going to sway a bit in a 60 MPH wind. You're basically driving in a tornado at that point. And any car that doesn't have extremely good suspension and aerodynamics, is going to sway a bit when a tractor trailer passes you at interstate or autobahn speeds; even when there is absolutely no wind at all. The sheer force of a giant semi truck passing through the air at 60-70 MPH creates a huge disruption to the air around it. A stock Fiero of any type is going to experience some sway being passed by a tractor trailer at those speeds, especially one with 25 year old suspension components.
The Superbird/Daytona wing did nothing for reducing drag coefficient. They were sold as options on the production cars so people could basically buy the exact same thing that was being run on the track, at the time. The wing on those cars was made to increase down force at speed. The design is vastly different to what is on the Fiero.
As for that Porsche spoiler, surface area is only a very small part of the puzzle. Do you have any actual wind tunnel testing data for anything?
LOL. So, no, of course you don't have any credible references to point to. You only have poor assumptions from the experience of driving. Any car is going to sway a bit in a 60 MPH wind. You're basically driving in a tornado at that point. And any car that doesn't have extremely good suspension and aerodynamics, is going to sway a bit when a tractor trailer passes you at interstate or autobahn speeds; even when there is absolutely no wind at all. The sheer force of a giant semi truck passing through the air at 60-70 MPH creates a huge disruption to the air around it. A stock Fiero of any type is going to experience some sway being passed by a tractor trailer at those speeds, especially one with 25 year old suspension components.
The Superbird/Daytona wing did nothing for reducing drag coefficient. They were sold as options on the production cars so people could basically buy the exact same thing that was being run on the track, at the time. The wing on those cars was made to increase down force at speed. The design is vastly different to what is on the Fiero.
As for that Porsche spoiler, surface area is only a very small part of the puzzle. Do you have any actual wind tunnel testing data for anything?
Roger posted his opinion about what he thought WKDFIRO was experiencing. WKDFIRO did not post any testing data and I couldn't help notice that there were no links in your explanation of the Superbird wing.
Have we gotten to the point that our own experiences and knowledge mean nothing? I think Roger may be onto something. There is nothing in the wind tunnel data that supports WKDFIRO's experience or his seat-of-his-pants evaluation of it. Sometimes we just need to have guys posting what happened to them and what their thoughts about it are.
And I will tell you right now, that GM wouldn't have put it on there if it was only functional at 165 MPH... It is there to reduce the coefficient of drag, not create a significant down force. It was measured and reported by R&T. A picture of a wide-bodied race car with a whale tail doesn't mean much of anything to the owner of a stock bodied Fiero with it's little wing...
There is a great article out there that I wish I could find that examined the effect of different OE spoilers and lips on the aero of sedans and coupes... I wish I could remember where I found it. It wasn't Fiero specific, but there were quite a few examples that were very similar and what the goal was for the different types of design.
And no... with 25" tires, a top gear of 1.0 and final drive ratio of 3.33... not to mention the fact that the TCC unlocks at WOT... I have not had it up to 165 MPH.
Originally posted by Boostdreamer: Roger posted his opinion about what he thought WKDFIRO was experiencing. WKDFIRO did not post any testing data and I couldn't help notice that there were no links in your explanation of the Superbird wing.
Have we gotten to the point that our own experiences and knowledge mean nothing? I think Roger may be onto something. There is nothing in the wind tunnel data that supports WKDFIRO's experience or his seat-of-his-pants evaluation of it. Sometimes we just need to have guys posting what happened to them and what their thoughts about it are.
In the video you can clearly see the smoke flowing over the rear glass and never touching the wing.
Posting experience and documenting what you feel is fine. But claiming it as undeniable fact with no references is not. Wind tunnel testing will never support WKDFIRO's comments, because it requires the vehicle to be moving with appropriate suspension loading, to test, and that doesn't happen in wind tunnels. Even on a dyno in a wind tunnel would not be sufficient, as inconsistencies in the road surface contribute to instability in the rear suspension. However, the design of the Fiero spoiler does make his claim plausible, as it acts more like a diffuser than a typical wing/spoiler.
Removing the front fascia completely having no effect at legal speeds, as rogergarrison claims, however, is just nonsense. Removing the fascia would result in a fairly large CD increase, as the front of the Fiero chassis is a flat steel panel. It would have an immediately measurable impact on fuel economy. The impact of the spoiler on fuel economy however, is not immediately measurable. It would take months, or even years, of extremely consistent driving, to show tangible results, outside of strict numbers as tested in a controlled environment, like a wind tunnel. People think a CD reduction of 0.01 is insignificant, because they can't "feel" it, or won't notice it immediately.
Originally posted by carbon: A picture of a wide-bodied race car with a whale tail doesn't mean much of anything to the owner of a stock bodied Fiero with it's little wing...
I know Cali was goading you with the 165 MPH thing, but I thought it was interesting that you made this statement.
It should matter. It's hard to understand, but the vapor in that picture would be in the exact same position on a stock bodied Fiero GT, with a stock spoiler. The IMSA might be a widebody with a whale tale, but the IMSA has the aero nose, which has the same angle as the stock nose, and it has the stock windshield rake, and the roof line is exactly the same. The whale tale spoiler on the IMSA is very similar to the stock spoiler in the effect it has on air flow. It's just a bit more of the same effect, and over a wider area, given it's a wide body.
A clean, shiny car always runs better than a dull, dirty one. Its exactly what always comes to my mind when someone says my car handles so much better after I put a spoiler/ wing on it. You cant help but laugh. None of the factory parts have any effect driving a car at legal speeds. You wouldnt have any real difference in performance if you took off the whole front bumper cover and drove it. Even Super Birds and Daytonas dont have any difference you could feel at legal speeds. * you 'might' feel some side sway driving in very hard wind conditions over 50,60 mph like a truck, or bus would.
