Curved or Straight air dam??

[sc2dave]

Originally Posted by sc2dave

Hmmm,i should be able to install a good size one on my 87 toy truck.It's still stock height. Approximately how much of a gain will this make?

anyone?

[sc2dave]

what about an airdam with a v shape?

[darrylrobida]

I believe that I'm getting a 4MPG increase on my CRX-HF with my custom
damm, that is blunt in the front. It is a daily driver that clears the speed bumps and curbs. It is a Straight air dam.

[Rurfen]

Any recommendations on how to attach one to a s-10? Is it necessary to drill holes through the bumper, below the tow hooks? I live in a heavily salted area in the winter and would rather not trill holes through the metal so I can minimize the surface area for salt to cause rust.

[kach22i]

Originally Posted by Rurfen

Any recommendations on how to attach one to a s-10? Is it necessary to drill holes through the bumper, below the tow hooks? I live in a heavily salted area in the winter and would rather not trill holes through the metal so I can minimize the surface area for salt to cause rust.

My S-10 has a plastic lower valance.

Step by step including all hardware:
Chin Spolier - fast/easy/cheap/effective - Pelican Parts Technical BBS

Chin Spoiler - fast/easy/cheap/effective

Extra deep garden edging 6" deep x 20 foot long coil purchased at ACE Hardware for approx. $12.00.
Secured straight up though the lip with a dozen Stainless Steel #8 Phillips screws 32 tread count, 1 inch long, lock nuts (nylon insert type) 9mm.

[TXwaterdog]

If you drill into your metal make sure to seal it with something. I personally like clearcoat (clearcoat spray/touchup paint) or silicon depending on what I'm putting through the hole. Most of the times I use both If I'm pulling wires that might move around. For cold fusion (nuts and bolts) I always dab some clearcoat on the inside of the holes and wait the proper amount of time for it to dry. Sure it's another step that takes 2hours+ but it's needed in my mind.

[aerohead]

Originally Posted by sc2dave

what about an airdam with a v shape?

A v-form has higher drag than a corner radius.They're better than a square corner but have no advantage than the more organic form.Hucho addresses this deep in his book.

[sc2dave]

Originally Posted by aerohead

A v-form has higher drag than a corner radius.They're better than a square corner but have no advantage than the more organic form.Hucho addresses this deep in his book.

Not for corners.What i mean is, from the center of the bumper,start the airdam from there and have the ends end up in front of the wheels.

[aerohead]

Originally Posted by sc2dave

Not for corners.What i mean is, from the center of the bumper,start the airdam from there and have the ends end up in front of the wheels.

If you take a look at the recent thread for the 2013 Chevy Malibu aerodynamics and watch the video from the wind tunnel,you'll see that the air is deforming well ahead of the cars body.This is Prandtl's line of discontinuity( My memory sucks,so watch me on this).
With just enough corner radius,the air will follow around a corner with perfectly attached flow,carrying all the useful kinetic energy rearward,hopefully to be properly decelerated in the aft-body for pressure recovery.
If you provide a 'V',the air can overshoot the corner,causing separation right then and there.
Also,it's been reported that a 'V' offers unstable acceleration compared with a curved surface within a favorable pressure regime.
Finally,the 'V' can produce local flow velocities which are incompatible with the velocity of the surrounding air mass,causing eddies and vortices to form as they meet,which cannot be harvested for kinetic energy downstream.This energy is lost forever to entropy.