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08-07-2020, 02:58 PM | #11 |
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Re: aerodynamic drag and body style
Stan,
1982 Camaro Berlinita
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08-07-2020, 03:36 PM | #12 |
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Re: aerodynamic drag and body style
An 1/8th mile bracket car will only be on the track for six seconds or so and a large portion of the run will be at a much lower speed than finish line speed which would make aerodynamics less important. I agree with Lee.
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08-07-2020, 04:00 PM | #13 |
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Re: aerodynamic drag and body style
I think 80's Monte Carlo with SS nose has CD of .34.
Question: If a car has more downforce then lift would go be faster if they were made equal? Last edited by Jeff Stout; 08-07-2020 at 04:01 PM. Reason: more |
08-08-2020, 12:17 AM | #14 |
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Re: aerodynamic drag and body style
When considering aerodynamics of drag racing cars/trucks, etc. The assumption of aerodynamic drag only has an effect at speed is incorrect. One can think of the issue becoming important at any speed over 40mph and the aero drag resistance is exponential to the speed very closely following the square law and more. That becomes a lot of free power by cleaning up (legally of course) the aerodynamic drag for the vehicle. Lots of rules of aero thumb to apply, but it is best to study and learn what can help with the selection of vehicles and how to improve them. An example is: external rear view mirrors cost about 0.6% in drag power.
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08-08-2020, 11:32 AM | #15 |
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Re: aerodynamic drag and body style
also tire width ,fender flares, ground effects ,spoilers, unnecessary openings in the grille area, upward lift attitude of the front end at speed as opposed to downward attitude--elimination of any unnecessary body parts ( mirrors etc.) ---all these affect airflow over under and around the vehicle ---You want to make the vehicle silohuette as smooth as possible ( within any rules restrictions course)--as vehicle speed increases it becomes of paramount importance to consider all of these----look at a jellybean as opposed to a brick and or a Corvette vs. a Van and you will get the idea--- modern auto manufacturers go to great lengths in "styling" their products not only for looks but to achieve the tinyest of drag reductions to increase fuel mileage
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08-08-2020, 12:31 PM | #16 |
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Re: aerodynamic drag and body style
I remember reading an article by Lingenfelter back in the early 70's.On his S/S 69 Camaro rag the car picked up a bit of MPH using only the front spoiler,and lost using the rear.The car would MPH around 115.In those days you would have to run both (as part of the SS package) or none at all.On my '71 it picks up about a 1/2 a MPH (more in a strong headwind) with the front spoiler...gsa612
Last edited by gsa612; 08-08-2020 at 12:37 PM. |
08-08-2020, 01:56 PM | #17 |
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Re: aerodynamic drag and body style
Larry I ran a 82 z28 with the ground effects and I had a large rear deck wing, car was very stable at 185 mph in 1/4 mile..LOL
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08-08-2020, 02:27 PM | #18 |
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Re: aerodynamic drag and body style
On a 79 Malibu wagon the factory rear spoiler is worth almost 3mph on car that runs just at 100 without it in the quarter.. and the reason for it is that it pulls air from the roof and routes it down the back window (to keep it clean in civilian life) which fills in the vacuum hole behind the car. and if you're wondering how big and powerful that "vacuum hole" is, it is what the cars that make turns use to create their ground effects downforce in sufficient quantities to be able to drive one across the ceiling upside down. The "vacuum hole" is also the reason behind drafting in nascar, if you can get in close enough it will damn near pull you along... need proof of what good aero can do? How about 174 on a bicycle...peddling.
what you really want to do with the front of the car is to smooth the air and keep it out from under the car, along the sides and roof you need to keep it flowing smoothly, and a the back you need to eliminate the "vacuum hole"... Jackie |
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08-08-2020, 02:42 PM | #19 |
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Re: aerodynamic drag and body style
You will find here 2 articles to add more details to this post.
https://www.scientificamerican.com/a...es-in-golf-ba/ https://www.grc.nasa.gov/WWW/K-12/ai.../boundlay.html I also like the FED387 informations regarding the one hand out of a car test... (relate to the coefficient of aerodymanic when the front of the car is more up in the air) Enjoy, Charles Stewart |
08-08-2020, 03:47 PM | #20 |
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Re: aerodynamic drag and body style
The above post gave me the idea to cover the surface of my Camaro with dimples. Maybe use a small ball pien hammer or leave it outside in a Texas hail storm.
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