^^ +1
I guess that's why my GTR does not have a spoiler
If the wing is angled at the correct spot, it will improves aerodynamic performance at high speed.
To increase drag or generate down force, helps stabilise the rear of the car = More control = Faster you go.
The angle of attack of the wing on some cars can be adjusted to increase downward force over the rear wheels, but it has the dual result of increasing drag.
Too much drag = Slow you down.
Your R33 GTR and Nathan's R34 GTR wing / blade / spoiler can be adjusted to a certain angle.
Nismo released a Boot Lip Spoiler for the R32 GTR to increase more down force as the stock spoiler for the R32 GTR was in a fixed position.
To actually test to see if the adjustment of the wing / blade / spoiler has made any improvement, you need to test it through a Wind Tunnel.
Or at the engineering department of the car manufacture themselves.
Or take it out to a race track and hammer it hard down the straight and through a corner to see if you notice any improvement in handling.
Unfortunately, majority of the shit cars running with GT Wings for street use are mostly used for cosmetics = Fucking ricers!
Until you goto a track day and see the GT Wings, it is all for a purpose.