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Paul9 · 04-01-2016, 09:45 PM

Hi people,

I have a Suzuki Swift which I converted to electric. I think the Swift body shape is the same as, or similar to, a Metro and the Holden Barina. I have some plastic angle, one side being 50mm wide and the other side being 75mm wide. I have about 3 metres of it.

I have already totally closed off the grill and added a kamback, front wheel spats and deleted the mudguards and radio attenna. I would now like to add a front airdam and I obviously have the choice between a 50mm (2 inch) or 75mm (3 inch) airdam.

Currently the front bumper is roughly 8 to 9 inches (approx 220mm) above the ground and the front suspension appears to be about 2 inches (50mm) lower than that.

I suppose my first question is - does an airdam actually help aerodynamics? I have done considerable research wherein opinions and some tests vary between "Cd can actually get worse with an airdam" to "Airdam gave me a 7% improvement" or "Depends on how big your airdam is."

It appears to me (and I am a real dummy!) that the purpose of an airdam is to get the air flowing around the vehicle rather than underneath. With less air travelling underneath the car there is less pressure and therefore an increase in downforce. An increase in downforce should increase my rolling resistance and therefore negate the benefits of reducing drag(??).

My second question: In an attempt to negate some drag I was wondering if maybe I could shape the airdam in the shape of a "U"? In other words, instead of following the existing bumper right along to its edges and then doing a 90degree turn to follow the sides of the vehicle back to the front wheel wells, maybe I could have the front three feet (one metre) of the airdam follow the bumper bar and then curve it back to the front of the wheel wells. While the front three feet of the airdam will be flush and flat with the bumper, the curve back to the wheels would give the air travelling to the side of the car, less resistance?

I apologise if I have not described this clearly. Any opinions about my idea?

Many thanks in advance
Paul

04-01-2016, 09:45 PM	#1 (permalink)
Paul9 EcoModding Lurker Join Date: Sep 2015 Location: Sydney, Australia Posts: 3 Thanks: 3 Thanked 1 Time in 1 Post	Modified shape for Airdam? Hi people, I have a Suzuki Swift which I converted to electric. I think the Swift body shape is the same as, or similar to, a Metro and the Holden Barina. I have some plastic angle, one side being 50mm wide and the other side being 75mm wide. I have about 3 metres of it. I have already totally closed off the grill and added a kamback, front wheel spats and deleted the mudguards and radio attenna. I would now like to add a front airdam and I obviously have the choice between a 50mm (2 inch) or 75mm (3 inch) airdam. Currently the front bumper is roughly 8 to 9 inches (approx 220mm) above the ground and the front suspension appears to be about 2 inches (50mm) lower than that. I suppose my first question is - does an airdam actually help aerodynamics? I have done considerable research wherein opinions and some tests vary between "Cd can actually get worse with an airdam" to "Airdam gave me a 7% improvement" or "Depends on how big your airdam is." It appears to me (and I am a real dummy!) that the purpose of an airdam is to get the air flowing around the vehicle rather than underneath. With less air travelling underneath the car there is less pressure and therefore an increase in downforce. An increase in downforce should increase my rolling resistance and therefore negate the benefits of reducing drag(??). My second question: In an attempt to negate some drag I was wondering if maybe I could shape the airdam in the shape of a "U"? In other words, instead of following the existing bumper right along to its edges and then doing a 90degree turn to follow the sides of the vehicle back to the front wheel wells, maybe I could have the front three feet (one metre) of the airdam follow the bumper bar and then curve it back to the front of the wheel wells. While the front three feet of the airdam will be flush and flat with the bumper, the curve back to the wheels would give the air travelling to the side of the car, less resistance? I apologise if I have not described this clearly. Any opinions about my idea? Many thanks in advance Paul