jlmccuan
06-24-2008, 08:12 AM
Has any one seen or used an extraction duct to help move air pooling under the hood out and help move air through the radiator and aftercooler? Is there enough volume and lack of turbulence under the car to create a venturi or scavenging effect? I am thinking that this could serve 2 purposes. Cooling as well as handling at higher speeds.
Input?
dqhemi
06-27-2008, 10:56 AM
Has any one seen or used an extraction duct to help move air pooling under the hood out and help move air through the radiator and aftercooler? Is there enough volume and lack of turbulence under the car to create a venturi or scavenging effect? I am thinking that this could serve 2 purposes. Cooling as well as handling at higher speeds.
Input?
For real high speed stuff that is part of the aerodynamics of the vehicle - internal aero. When I was open road racing we tried to manage the airflow into the engine bay and back out again. Cold air box on the rad, and intercoolers were fully ducted in and back out into the fenderwell. For that car it was also feasible to open up the fender wells some to help evacuate the engine bay.
Extraction ducts will work as well, but not at real high speeds. Shelby Daytona did this effectively and doing it properly can create downforce.
As far as scavenging goes, a properly designed air dam will minimize the amount of air going under the car and create a low pressure area underneath which reduces lift (or creates downforce) and does help the engine bay to evacuate as that is the natural place for airflow to go. Ideally you want to manage the aiurflow into the engine bay and back out again, which is almost impossible to do on a production car, but there are things you can do which will help alot.
Sorting out the are for high speeds, i.e. eliminating lift, will make the car handle much better as well.
I wouldn't spend any time on this unless you're planning on running over say 180 MPH for extended periods of time. In my case we were running over 200 and trying to go faster...