A few years ago, myself and some fellow students built an active aerodynamics prototype wing for an engineering design project. We installed it on my Fiero for testing and I had posted a few videos:
The project was donated to our university where its been sitting for a few years. Recently, some new students decided to continue on with our project and contacted myself and my former group members for any information we had pertaining to the project. It turns out that they were able to secure some wind tunnel testing time at the GM facility on the campus and they need a car for the testing...
I volunteered my Fiero so in the next few weeks you may see a Fiero in a state of the art wind tunnel facility! I will of course be attending and I'll try and take some video. I'm hoping I can also see the effect of my headlight upgrade + hood vent.
Is there anything you guys are interested in seeing? I'm not sure how much time we'll have in the wind tunnel but maybe they'll be able to test a few things. Post your suggestions below! ------------------ Check out my build and my website! https://www.fiero.nl/forum/Forum3/HTML/000100.html Embrace Racing
[This message has been edited by doublec4 (edited 03-22-2016).]
One of the things that seems to come up at least once a year is the effectiveness of the stock wing. There's the claimed 80 lbs of down force at highway speed, but it would be nice to finally put that one to bed with some hard data. It would also be interesting to see how changing the height of the wing affects down force, etc.
As for roof scoops, I don't have any so it's probably not going to be something I can test. Also, just by look at them I would venture a guess that they are doing more harm than good.
Stock spoiler is something else I don't have. I have an IMSA wing on my notchie that I may be able to use as a bench mark.
Keep in mind there probably won't be enough time to install/uninstall a ton of parts. I think what I'm after here is to get any suggestions of specific areas that may be of interest.
I saw the numbers from the stock nose car and know first hand you can even feel the lift start around 90 MPH. The hood vents are very effective as well the air damn.
The hood vent may shoe your best improvement.
As for the factory wing even GM stated there was no down force back in the day. There will be nothing real to find other than it it lowers drag count as GM did claim.
Now if you do use a wing that adds down force it would be interesting to see how much it adds to the drag count and how much HP it requires to use it. This is why the factory never wanted down force. One it was not needed and when you are pushing only 140 HP the last thing you want to do is add drag to a car needing all the HP they can use.
Might also try wider and skinnier tires. I have always seen tires are a big aero factor on race cars and even street cars. It would be interesting to see how much change it would be to go from the factory size to wider aftermarket.
Also the wrap around spoiler. It would be interesting to see if it holds any effect and just how much. The real race wings has a little larger area and I always wondered if the street had much effect.
Probably not feasible with what the OP is doing, but I'd like to see side by side tests in the same wind tunnel of a Notchie, Notchie with the Indy nose and a GT. We all have our preferences from a 'looks' perspective, but I'd like to know the difference performance wise.
Probably not feasible with what the OP is doing, but I'd like to see side by side tests in the same wind tunnel of a Notchie, Notchie with the Indy nose and a GT. We all have our preferences from a 'looks' perspective, but I'd like to know the difference performance wise.
Also, a test of Headlights UP compared to Down.
As per GM's own wind tunnel testing, base notchback has the highest cD of the three, aero notchie a little less, fastback a little less, and adding the OEM wing reduces it another 0.01.
Headlights UP significantly increases drag and distrubs air flow. See the video I posted earlier in the thread.
I'm very surprised they were able to secure any time in GM's Wind Tunnel, it's generally booked up way in advance and very expensive. Could this mean GM doesn't have a lot going on in new design ?
Since GM has all baseline numbers, the group should focus on testing changes that they feel will make the most improvement and test in that order.
I'm very surprised they were able to secure any time in GM's Wind Tunnel, it's generally booked up way in advance and very expensive. Could this mean GM doesn't have a lot going on in new design ?
Since GM has all baseline numbers, the group should focus on testing changes that they feel will make the most improvement and test in that order.
I'm sure they have quite a bit going on, since it's not a GM exclusive wind tunnel. I'm sure it's one of many that they use but it was largely funded by GM so I believe they have priority when it comes time to booking. It is part of the university campus and I'm not sure how allotted time was set aside for a student project. However, I'm not going to ask too many questions
Does the add on deflector for the door mirrors do anything? /other.
Now that would be cool,I can send a set off of my 87 to you to test...not hard to put on and then take right back off.Want cost a thing to ya just shoot me your addy.
[This message has been edited by fireboss (edited 03-24-2016).]
As per GM's own wind tunnel testing, base notchback has the highest cD of the three, aero notchie a little less, fastback a little less, and adding the OEM wing reduces it another 0.01.
Headlights UP significantly increases drag and distrubs air flow. See the video I posted earlier in the thread.
I always though the car with the lowest cD was with the aero nose, but a notchback rear (i.e. 84 pace car, 85 GT, 86 SE). Specifically, I thought the fastback cD was .36 while the 85 GT body was .34.
I always though the car with the lowest cD was with the aero nose, but a notchback rear (i.e. 84 pace car, 85 GT, 86 SE). Specifically, I thought the fastback cD was .36 while the 85 GT body was .34.
Does anyone have a hard authoritative source?
quote
From https://www.fiero.nl/forum/A...710-2-047951.html#p5 (Autocar Mar 13th 85) The base fiero (4 cyl coupe (with 13 inch wheels) is 0.377 The Coupe (with wider 14 inch wheels and tires) is 0.406 GT notchback without spoiler is 0.370 (Car & Driver Nov 84) The GT notchback (includes Indy) with rear spoiler is 0.350
(Sports and GT cars, Dec 87) Fastback GT with spoiler 0.340
Fastback is least drag. Makes sense from a laypersons point of view the longer side sails probably make the wind go around smoother, the wing keeps it up out of the "pocket" better.
[This message has been edited by 2.5 (edited 03-24-2016).]
Fastback is least drag. Makes sense from a laypersons point of view the longer side sails probably make the wind go around smoother, the wing keeps it up out of the "pocket" better.
The so called Wing is really a Spoiler that prevents/minimizes "backdraft air from crawling up over the rear decklid (going forward and up) and getting into air stream that has come over the roof (if it gets in that air stream zone it cause causes shock waves forward disturbing air stream causing resistance/drag. It is the most mis-understood parts of the aero package.
There been talk about the airflow through the engine vents. Can that be proof tested that the air does go up through them and not down?
I wanted to test that myself, but didn't have access to a wind tunnel. So I attached a bunch of pieces of string to the decklid vent and drove the car around. I did the test in 2 parts, first with a stock decklid vent and then with a modified one (for more airflow). Here is the result:
As you can see in the video, the stock vent doesn't flow much air at all. There's hardly enough airflow to move the strings. But remove the airflow restrictions and you get a strong updraft at speed.
Here's another one, showing how the pop-up headlights disturb airflow over the hood:
I know having a hood vent will help, especially if you remove the front tub. I want to see that. Also I want to see a hatchback 350z glass Fiero.
The hatch on the fastback will give a decent reduction in cD, perhaps as much as 0.03, which, with the factory wing, would bring the cD down to about 0.32, which is where the 300ZX was. A choptop with hatch would bring it even lower, perhaps down to 0.30 or 0.29, which is where the 350Z is.
Given the structure of the front end, I would expect removing the plastic tub to negate much of the effects of adding a hood vent, in terms of aerodynamics. Perhaps some more interesting channeling could be built with carbon fiber or similar instead, to be able to retain the aerodynamic (and storage) benefits of the tub, while forcing the excess heat out above the car, without obstructing the flow of cool dense air underneath.
Okay so thanks to Canadian Border Services Agency I will not be making the deadline for this weekend. I was waiting on two packages from ZZP performance to arrive sometime last week... instead they sat in the CBSA sorting facility for over a week with no progress and no ability to contact them and inquire about the status of my shipment. One of them arrived today and the other is supposed to arrive by the end of the week which doesn't give me enough time to get my car back on the road by Sunday.
However, the good news is that I spoke with the group member who spoke with the director of the wind tunnel... it sounds like he would be happy to allow further testing some point in the summer... so until then... I should plan a few more aero "upgrades" and see what actually happens in the wind tunnel a few months from now!
if you can, painters tape, the good stuff, and tape up the turn signal holes, and test and then the grill opening..
I'm willing to bet, blocking off the cooling hole in the areo nose will bring the best areo, an added lower airdam would add to this, and making the car a bottom breather like the 3rd gen f body, and the hood vent in the fiero hood will cool it more than enough..
Just to follow up... I never got my car in the wind tunnel, but a Fiero did get to go, along with the original wing that we built a few years back:
As the focus was on their project, and time was very valuable, only the wing was tested. It actually worked and did what it was intended to do. The drag penalty seemed high to me, but I don't have any other wings to compare it to so I'm not sure. Either way, if someone wanted to create something like this, they can just pick a different airfoil.
.....
I'll see what I can do!
