aerodynamic drag and body style - Page 4

Adger Smith · 08-09-2020, 11:29 AM

Note the difference in the SS legal rear spoiler on my car and the RMS wing.

AJ Laferty · 08-09-2020, 12:03 PM

Ever seen an airplane with propellers (vice jet) with a squared off tail? Go to http://www.landracing.com/forum/index.php?board=52.0 for a good discussion about aero.

SSDiv6 · 08-09-2020, 07:35 PM

Aerodynamics is a complex subject and the results are dependent in many factors. The dimpled surface acts like a vortex generator and the size and location of the dimple. It is also affected by the shape and angle of incidence as referenced along the axis of the object.

In the 1990's when WJ was racing his Firebird Pro Stock, GM brought his car to the Georgia Institute of Technology and with the assistance of Boeing engineers, they spent considerable time working on the car to improve it. They ended changing the body panels and rake of the car. When Warren showed up at the Winternationals, the car went fast, got protested and ended hammering the quarter panels and putting duct tape.

If you want to see the aero effects, just tape wool strings to the body and take pictures and video. Done this in the past in airplane projects I had worked on and even Chrysler did so with the Mopar Missile in the early days of Pro Stock.

Mike Rietow · 08-10-2020, 09:40 AM

Damn I hate to put a flat wing on a factory condition 66 Chevy II.

Signman · 08-10-2020, 10:25 AM

Here we go, I run a 3rd Gen Camaro in Stock which sometimes is pretty fast. Built the car from scratch from a street car disassembled pretty much completely then reassembled as a legal stocker with stiff chassis and weight bias advantage etc.

These cars are bottom breathers if you must run a flat hood. Was never in doubt about keeping the air dam under the radiator to keep air flow and pressure in front of the radiator to assure fresh air flow to the throttle body. Use your imagination to take advantage of this with a carb, the fast guys already know. Some advise received from a very experienced racer was to seal up the area from air inlet/grill to the front of radiator area to not allow it's escape from the front of the radiator would help aero, and may help fresh air to the TB/Carb.

Another benefit of running the lower air dam (just my theory) is that it will help speed air flow under the car (along with lowering the body) not having as much getting caught up the open areas under the engine and flowing more smoothly under the trans & floor pan, can't do much about the rear axle area.

Hope this helps.
Thanks to Ray Valpreda for his thoughts and info expanding my thinking.

08-09-2020, 11:29 AM	#31
Adger Smith VIP Member Join Date: Dec 2001 Location: Texarkana Ark/TX Posts: 2,446 Likes: 575 Liked 880 Times in 311 Posts	Re: aerodynamic drag and body style Note the difference in the SS legal rear spoiler on my car and the RMS wing. Attached Thumbnails __________________ Adger Smith (Former SS)

08-09-2020, 12:03 PM	#32
AJ Laferty Junior Member Join Date: Dec 2013 Location: Elizabeth City, NC Posts: 47 Likes: 80 Liked 25 Times in 9 Posts	Re: aerodynamic drag and body style Ever seen an airplane with propellers (vice jet) with a squared off tail? Go to http://www.landracing.com/forum/index.php?board=52.0 for a good discussion about aero. __________________ Jeff Laferty Suffolk, VA

08-09-2020, 07:35 PM	#33
SSDiv6 VIP Member Join Date: Feb 2003 Location: Glendale, Arizona Posts: 3,023 Likes: 706 Liked 1,514 Times in 563 Posts	Re: aerodynamic drag and body style Aerodynamics is a complex subject and the results are dependent in many factors. The dimpled surface acts like a vortex generator and the size and location of the dimple. It is also affected by the shape and angle of incidence as referenced along the axis of the object. In the 1990's when WJ was racing his Firebird Pro Stock, GM brought his car to the Georgia Institute of Technology and with the assistance of Boeing engineers, they spent considerable time working on the car to improve it. They ended changing the body panels and rake of the car. When Warren showed up at the Winternationals, the car went fast, got protested and ended hammering the quarter panels and putting duct tape. If you want to see the aero effects, just tape wool strings to the body and take pictures and video. Done this in the past in airplane projects I had worked on and even Chrysler did so with the Mopar Missile in the early days of Pro Stock.

08-10-2020, 09:40 AM	#34
Mike Rietow Junior Member Join Date: Apr 2017 Posts: 93 Likes: 19 Liked 30 Times in 16 Posts	Re: aerodynamic drag and body style Damn I hate to put a flat wing on a factory condition 66 Chevy II. __________________ 7x S/Pro 'Sunshine" http://ottm.store https://youtu.be/I8QWEaqeFRw

08-10-2020, 10:25 AM	#35
Signman Senior Member Join Date: Oct 2003 Location: Lower Slower Delaware Posts: 535 Likes: 22 Liked 269 Times in 99 Posts	Re: aerodynamic drag and body style Here we go, I run a 3rd Gen Camaro in Stock which sometimes is pretty fast. Built the car from scratch from a street car disassembled pretty much completely then reassembled as a legal stocker with stiff chassis and weight bias advantage etc. These cars are bottom breathers if you must run a flat hood. Was never in doubt about keeping the air dam under the radiator to keep air flow and pressure in front of the radiator to assure fresh air flow to the throttle body. Use your imagination to take advantage of this with a carb, the fast guys already know. Some advise received from a very experienced racer was to seal up the area from air inlet/grill to the front of radiator area to not allow it's escape from the front of the radiator would help aero, and may help fresh air to the TB/Carb. Another benefit of running the lower air dam (just my theory) is that it will help speed air flow under the car (along with lowering the body) not having as much getting caught up the open areas under the engine and flowing more smoothly under the trans & floor pan, can't do much about the rear axle area. Hope this helps. Thanks to Ray Valpreda for his thoughts and info expanding my thinking. __________________ Frank Ferrucci I/SA 1271 "Be Thankful for the Gifts You are Given"