Lanny Curlett

As you can see I have a high wing on my car. It certainly planted the a** end of the car. In e mail discussions with Mike Warner of IFC he stated that he didn't see the benefits to the "clean air" argument for high wings and pointed out so many factory hatchback type cars (959 etc) ran at very high speeds with much lower wing heights and some ran with a deck spoiler. He also stated the high wing thing came from the old Daytona Charger / Plymouth Superbird days and the only reason they ran them on those cars was clearance to open the trunk! (Which, ironically, I cannot do on my car. Open the hatch that is.) What are the thoughts from the racing crowd? High or low? Mike at IFC made my splitters and hoods and showed me someprojects he has worked on and is still working on. Smart guy! Innovative and a thinker. OK. Let's talk.

Willard Bridgham 3

How any wing works is a function of surface air pressures. Do you have a surface pressure plot?

gencollon2

I do not know of any CFD models of 944s, but flow visualization is helpful for this sort of thing.

look up yarn tufts if you haven't seen them. It wouldn't be that difficult to create a couple different height wing mounts, tuft the wing, and the hatch, and use a couple of GOPRO cameras to find the height where the turbulent flow off the roof makes the wing less effective.
Maybe somebody here has made a 3d model of a 944 and a CFD program, but again, I don't and haven't seen it yet.

333pg333

Lanny all I can say is that I'm pretty sure that wing would be creating almost as much drag at it is downforce. From the bit of research and advice that I've received by people imminently more qualified than me, they would suggest it sitting a little lower and a little more rearwards than what I 'think' I'm seeing in that pic. However this is tempered with the need to balance the front. You can't keep adding rear wing without it having a big effect on the front end. Little bit hard to tell from that pic just how far the splitter protrudes but the whole aero 'system' on that car looks pretty agricultural with all due respect. It also appears that you're running a lot of attack on the wing which would be creating more downforce but increased drag. Look to more modern cars with major aero on them like the DTM and Time Attack cars but also bear in mind that you need to check into your local rules. Many governing bodies have quite stringent restrictions and if you continue to win races they will come a knocking to check into your car with a fine toothed comb!

Duke

The angle of attack is too aggressive on the yellow car. Hardly any single element wing can do more than 12 degrees without stalling. Reduce the AOA and you will gain downforce.

The reason to have the wing high up is to put it in a clear airflow. This is a higher problem for sedans with a sharp downwards angle of the rear windscreen. That creates a whole lot of turbulence and separation. But with the long sloped shape of our rear hatch this is less of a problem, but the wing still needs to be a fair bit above the hatch for maximum effectiviness.

The reason we haven't seen that on all race cars is usually restrictions in the rules. But how wings looked and were positioned some 30 years ago is not really relevant today and what we "know" today.

Positioning the wing rearwards creates more leverage and if it's really rearwards you can benefit from the fast exit air from a rear diffusor to increase the wing downforce.
The rearwards position is usually also restricted by rules. However, the more rearwards it sits the more lift you get on the front due to the leverage.

The benefits with choosing a long and wide wing is that you can run it at a low AOA and still get lot's of downforce but with less drag.

Lanny Curlett

Thanks for the input all of which makes sense. My crew told me that my wing was visbly bending down in the middle on the straightaway so the AOA reduction comment is probably bang on. I have 4.5 inches of splitter protruding from the front. There are quite a few wings available for our cars and I would really like to hear from you guys which wing you use and why you chose it. This GT racing wing was chosen by myself basically because of ease of acquisition. Competition Engineering has a wing supposedly designed for these cars. I'll find a link and post it.

disasterman

GoodAero by Scott Good, you can check out the website for more information. These work very well, I am currently running a 4 degree angle of attack.

dizzyj

What splitter do you run with that? ^^

Lanny Curlett

I have a custom splitter manufactured by IFC. They sandwiched a sheet of thin aluminium on the leading edge and back 6.5 inches to accomodate turnbuckles and other strong attachments. Nice piece.

Lanny Curlett

The splitter.

disasterman

I am using a splitter designed by my fabricator that I manufacture and sell. You can also see it on the GoodAero site. My spitter utilizes a three piece bracket that bolts replaces the factory tie downs using the same bolts. The splitter board can be removed for loading onto a trailer via two bayonet mounts. The fascia extension is ABS plastic that attaches to the factory fascia batwing mounts. There are about 15 of them being raced around the midwest and greatlakes NASA region.