GT4 Aero Adjustment
#47
He's posted something about Bahrain International previously
#49
Rennlist Member
I tried removing the slats when I brought the car home. It looked like there were 4 Torx screws but when I removed them, the flap was still connected. From the picture posted previously, there are two metal tabs what appear to be behind the flap. How do you release the flap?
Thanks!
Thanks!
#50
Burning Brakes
So, I decided to do a little testing on the whole wing thing.
I wanted to do the adjustment but was wondering if there was any real adjustability based on comments from those that have tried, and was also concerned about the brake light warning and generally err on the side of caution.
Adjustability
I loosened the rear bolts with a T30 Torx mini-wrench and a T30 Torx screwdriver. First realization was that - although the torque specs are something like 6lbs there is thread lock on the bolts and they take a hell of a twist to initially loosen (definitely recommend a mini-wrench and taking your watch off in case your hand slips and scratches the paint on the trunk).
I couldn't verify the wing angle per se as I have no idea what reference point they used for calculating the angle of a curved wing, so I did the next best thing.
I placed a Wixey Angle Gauge on the wing and zeroed it out, so that my reference point for the factory wing setting was zero. I kept the angle gauge in exactly the same spot while adjusting the wing, which as others have stated requires a complete removal of the bolts. After adjustment you can see that the difference reads as 2.5 degrees. I've seen different readings for the wing angles (Jalopnik said 4.5 and 7 whereas Ian Kuah's article said 5 and 7) but what I can say is that I'm definitely reading a 2.5 degree difference based on my simple test. Now that's hardly like activating an air brake, but it is consistent with the largest supposed difference I've seen so I feel like they gave us exactly what they said they gave us.
Before - 0
After - 2.5
Brake Light Visibility
This is very much a laymans's way of testing brake light visibility but I wanted to try to make it real-world. So, I sat in my sedan with the door open and measured with tape from my eye to the ground. I got 46.5 inches from eye to ground.
I then got someone to press the brake to activate the light as I stood behind the car about 5 feet, crouched so that my eyeline was again 46.5 inches from the ground (as if I was in a sedan and tailgating my GT4).
You can see the results from the photograph. The brake light is clearly and fully visible. I think I'd have to be tailgating on my 4 year old son's Thomas the Train bike to have any chance of having my view of the brake light impeded.
So, there you go. Hardly scientific but it's enough for me.
I wanted to do the adjustment but was wondering if there was any real adjustability based on comments from those that have tried, and was also concerned about the brake light warning and generally err on the side of caution.
Adjustability
I loosened the rear bolts with a T30 Torx mini-wrench and a T30 Torx screwdriver. First realization was that - although the torque specs are something like 6lbs there is thread lock on the bolts and they take a hell of a twist to initially loosen (definitely recommend a mini-wrench and taking your watch off in case your hand slips and scratches the paint on the trunk).
I couldn't verify the wing angle per se as I have no idea what reference point they used for calculating the angle of a curved wing, so I did the next best thing.
I placed a Wixey Angle Gauge on the wing and zeroed it out, so that my reference point for the factory wing setting was zero. I kept the angle gauge in exactly the same spot while adjusting the wing, which as others have stated requires a complete removal of the bolts. After adjustment you can see that the difference reads as 2.5 degrees. I've seen different readings for the wing angles (Jalopnik said 4.5 and 7 whereas Ian Kuah's article said 5 and 7) but what I can say is that I'm definitely reading a 2.5 degree difference based on my simple test. Now that's hardly like activating an air brake, but it is consistent with the largest supposed difference I've seen so I feel like they gave us exactly what they said they gave us.
Before - 0
After - 2.5
Brake Light Visibility
This is very much a laymans's way of testing brake light visibility but I wanted to try to make it real-world. So, I sat in my sedan with the door open and measured with tape from my eye to the ground. I got 46.5 inches from eye to ground.
I then got someone to press the brake to activate the light as I stood behind the car about 5 feet, crouched so that my eyeline was again 46.5 inches from the ground (as if I was in a sedan and tailgating my GT4).
You can see the results from the photograph. The brake light is clearly and fully visible. I think I'd have to be tailgating on my 4 year old son's Thomas the Train bike to have any chance of having my view of the brake light impeded.
So, there you go. Hardly scientific but it's enough for me.
Last edited by IrishAndy; 11-06-2015 at 10:39 PM.
#51
Rennlist Member
So, I decided to do a little testing on the whole wing thing.
I wanted to do the adjustment but was wondering if there was any real adjustability based on comments from those that have tried, and was also concerned about the brake light warning and generally err on the side of caution.
Adjustability
I loosened the rear bolts with a T30 Torx mini-wrench and a T30 Torx screwdriver. First realization was that - although the torque specs are something like 6lbs there is thread lock on the bolts and they take a hell of a twist to initially loosen (definitely recommend a mini-wrench and taking your watch off in case your hand slips and scratches the paint on the trunk).
I couldn't verify the wing angle per se as I have no idea what reference point they used for calculating the angle of a curved wing, so I did the next best thing.
I placed a Wixey Angle Gauge on the wing and zeroed it out, so that my reference point for the factory wing setting was zero. I kept the angle gauge in exactly the same spot while adjusting the wing, which as others have stated requires a complete removal of the bolts. After adjustment you can see that the difference reads as 2.5 degrees. I've seen different readings for the wing angles (Jalopnik said 4.5 and 7 whereas Ian Kuah's article said 5 and 7) but what I can say is that I'm definitely reading a 2.5 degree difference based on my simple test. Now that's hardly like activating an air brake, but it is consistent with the largest supposed difference I've seen so I feel like they gave us exactly what they said they gave us.
Before - 0
After - 2.5
Brake Light Visibility
This is very much a laymans's way of testing brake light visibility but I wanted to try to make it real-world. So, I sat in my sedan with the door open and measured with tape from my eye to the ground. I got 46.5 inches from eye to ground.
I then got my someone to press the brake to activate the light as I stood behind the car about 5 feet, crouched so that my eyeline was again 46.5 inches from the ground (as if I was in a sedan and tailgating my GT4).
You can see the results from the photograph. The brake light is clearly and fully visible. I think I'd have to be tailgating on my 4 year old son's Thomas the Train bike to have any chance of having my view of the brake light impeded.
So, there you go. Hardly scientific but it's enough for me.
I wanted to do the adjustment but was wondering if there was any real adjustability based on comments from those that have tried, and was also concerned about the brake light warning and generally err on the side of caution.
Adjustability
I loosened the rear bolts with a T30 Torx mini-wrench and a T30 Torx screwdriver. First realization was that - although the torque specs are something like 6lbs there is thread lock on the bolts and they take a hell of a twist to initially loosen (definitely recommend a mini-wrench and taking your watch off in case your hand slips and scratches the paint on the trunk).
I couldn't verify the wing angle per se as I have no idea what reference point they used for calculating the angle of a curved wing, so I did the next best thing.
I placed a Wixey Angle Gauge on the wing and zeroed it out, so that my reference point for the factory wing setting was zero. I kept the angle gauge in exactly the same spot while adjusting the wing, which as others have stated requires a complete removal of the bolts. After adjustment you can see that the difference reads as 2.5 degrees. I've seen different readings for the wing angles (Jalopnik said 4.5 and 7 whereas Ian Kuah's article said 5 and 7) but what I can say is that I'm definitely reading a 2.5 degree difference based on my simple test. Now that's hardly like activating an air brake, but it is consistent with the largest supposed difference I've seen so I feel like they gave us exactly what they said they gave us.
Before - 0
After - 2.5
Brake Light Visibility
This is very much a laymans's way of testing brake light visibility but I wanted to try to make it real-world. So, I sat in my sedan with the door open and measured with tape from my eye to the ground. I got 46.5 inches from eye to ground.
I then got my someone to press the brake to activate the light as I stood behind the car about 5 feet, crouched so that my eyeline was again 46.5 inches from the ground (as if I was in a sedan and tailgating my GT4).
You can see the results from the photograph. The brake light is clearly and fully visible. I think I'd have to be tailgating on my 4 year old son's Thomas the Train bike to have any chance of having my view of the brake light impeded.
So, there you go. Hardly scientific but it's enough for me.
Andy you must have been Mr Wizard in your earlier life
#52
Burning Brakes
Just from looking at it, and then taking it apart earlier, what Andy says honestly doesn't surprise me ..... Its looks like the angle change its barely visible... That's not to say it doesn't work ... It just appears so slight of an angle change, that I would be hard pressed to believe one could actually see the difference
Andy you must have been Mr Wizard in your earlier life
Andy you must have been Mr Wizard in your earlier life
So, under the premise that going further is always better you gave me an idea... A small 2.5 degree change to the wing angle doesn't seem to block the brake light under reasonable conditions, but just how easily can we see that 2.5 degree difference? Is it slight, obvious, or non-existent? I was too busy messing about with the angle gauge on the first try to actually stand back and appreciate the difference (if any) that it made.
So, I placed a GoPro on a makeshift tripod and used the Wi-Fi app to try to place a strip of Scotch blue tape on the wall just above the top line of the rear wing in 'steep' setting. The idea was to give an obvious visual reference so that we could see how (or if) the gap between the wing and the tape line grew as I adjusted the wing back to the 'shallow' setting. After adjusting the wing back I took a second photo. I put this in a GIF so that it was easier to see the change. Hopefully it turns out.
Frankly I was surprised. While you're not going to walk up to a car with an adjusted wing and immediately go "Wow! That one's had its wing adjusted" the subtle change certainly noticeable to the naked eye.
Hopefully this makes it a lot easier for those that haven't tried it - or don't have their cars yet - to get a visual appreciation of the difference.
PS You can see my cheapo tool set on the floor in the second pic in the GIF
Steep:
Shallow
GIF
The following 2 users liked this post by IrishAndy:
911F1 (05-11-2022),
PorscheSitter (11-28-2021)
#53
Three Wheelin'
Nice gif Andy. I personally do not think this change will make a lot of difference for the majority of the driving I do. Even on my favorite track the fastest corner is in the 90 mile an hour range. Also do not believe it makes much of any difference to you straight line Speed.
#54
Rennlist Member
Very cool
#55
Thank You. Great visual.
#58
Drifting
Wow, thanks for taking the time to document this. We need a sticky thread with all these how-to's gathered in one spot.
#59
.2RS has a similar angle adjustment. I noticed the change in T2 (you can almost go flat out from T1 to T3) and T18 at COTA. It was worth about a second. I think Sport Auto said it was about 10KG additional on rear axle at 120mph, making it more than the 991GT3.