Hello -
I tried the C23 spring but it was too weak. Instead I went with the C21 spring :
This is closer to the results I originally wanted :
At 40 MPH it is closing but not quite closed :
At 40 MPH + my original C7 springs, it was fully closed.
At 50 MPH it is fully closed :
I am going to leave "v 2.0" alone for the week. Then I think my next step (on Deezler's advice) will be to reduce the size of the flap so that it reduces the frontal area. I want it to close over the intake vent, but not extend down as much. I will trim off the sides because they are not blocking anything that is not already blocked, are away from the hinge and are therefore subject to being more "flappy". Because of the reduced "wing area", I will "reset" to the original C7 spring. This is the plan :
This arrangement will (hopefully) test whether the extension is influencing my results.
From what others have posted, I also realize that I can "stack" the springs based on the weather. For instance, in July/August, I may "double-up" the springs to reduce the blocking effect. If I do it right, I won't have to sacrifice zip ties in the process.
CarloSW2
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