Great race aero article in GRM
#23
Thats my understanding of it, but that thinking does not make sense to me: If you have high pressure under the hood, you have lost the battle and you are getting front end lift. Reducing this is good in and of itself. You might get more air under the splitter, but thats where setting up the splitter properly is important. No matter how you slice it you are reducing lift and getting cooling in the bargain too.
Maybe they were thinking along the lines that many cars actually have high presure zones right around the cowl, meaning that an 'extractor' hood will actually get air reversion into the engine bay?
GRM is on the very short list of mags I actually read cover to cover every time. Note the lack of OEM worship they have. I love that.
#24
This month was an "aero" spectacular. Got my new GRM and the new Top Gear magazine the same day. You guys saw the GRM article. In top gear they had pics of the new Audi A4 GTM race car. It wasn't an aero article but that car itself is pretty much a lesson on aero all on it's own. Those two were followed by Car & Driver with a nice write up on the new Ferrari 599xx. A track only version of the 599. Lots of great aero info in that article too.
Here's the back of the Audi A4 GTM. It takes aero add ons to the extreme.
I was a dissapointed the GRM aero article didn't apply what they were talking about to a test car. I wish they would have taken a basic car and done some testing. Splitter, wing, diffuser, vents and the results of each.
Here's the back of the Audi A4 GTM. It takes aero add ons to the extreme.
I was a dissapointed the GRM aero article didn't apply what they were talking about to a test car. I wish they would have taken a basic car and done some testing. Splitter, wing, diffuser, vents and the results of each.
#26
BW, I loved the smooth bottom of the 599xx combined with the winglets to move air toward the rear spoiler and "puffs" of air to separate the turbulence as air leaves the back of the car. 1.5 Million for a track day/time trial toy. Amazing.
I have to reread the GRM article. I can't believe they wouldn't advocate vented hoods for aero. 80mph on the freeway I can see my unvented hood trying to lift. Allowing that pressure to escape is a well proven aero enhancement. Had to be a mistake in editing if they said that.
I have to reread the GRM article. I can't believe they wouldn't advocate vented hoods for aero. 80mph on the freeway I can see my unvented hood trying to lift. Allowing that pressure to escape is a well proven aero enhancement. Had to be a mistake in editing if they said that.
Last edited by cueball1; 04-06-2010 at 01:25 PM.
#30
i think this front splitter looks ridiculous, but i wouldn't drive that car without it.
http://images.search.yahoo.com/image...sigb=13i6hts62
#32
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http://antholonet.com/EngineersCars/...aparral2J.html
#33
(Flame suit on)
Is there any merit to the idea of running a ducted system through the trunk and out either the trunk lid or the trim plate around the license plate? The ducting would go down in front of the gas tank mre or less. So the vacuum at the back of the car naturally pulls air out from under the car to reduce both lift and drag.
Is there any merit to the idea of running a ducted system through the trunk and out either the trunk lid or the trim plate around the license plate? The ducting would go down in front of the gas tank mre or less. So the vacuum at the back of the car naturally pulls air out from under the car to reduce both lift and drag.
#34
No flaming. There's a whole lotta stuff to be tried. Without a wind tunnel at your disposal it's a whole lot tougher to quantify improvements. You can use lap times but only if you are super consistant and able to push 10/10ths all the time. You can also do high speed coast down runs in 2 directions on a known stretch of road but at the risk of police intervention.
#35
What about a small fan-like deal with a magnetic pick-up based RPM signal, like they use on a bike speedometer?
The faster it spins, the more air you have going through that area. All you need to do it calibrate it roughly to get an idea of what RPM corresponds to what speed, which you could do by strapping the thing to the roof.
Crude, but possibly effective. If you get similar velocity through the duct that you do on the roof, then good things are happening.
The faster it spins, the more air you have going through that area. All you need to do it calibrate it roughly to get an idea of what RPM corresponds to what speed, which you could do by strapping the thing to the roof.
Crude, but possibly effective. If you get similar velocity through the duct that you do on the roof, then good things are happening.
#36
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(Flame suit on)
Is there any merit to the idea of running a ducted system through the trunk and out either the trunk lid or the trim plate around the license plate? The ducting would go down in front of the gas tank mre or less. So the vacuum at the back of the car naturally pulls air out from under the car to reduce both lift and drag.
Is there any merit to the idea of running a ducted system through the trunk and out either the trunk lid or the trim plate around the license plate? The ducting would go down in front of the gas tank mre or less. So the vacuum at the back of the car naturally pulls air out from under the car to reduce both lift and drag.
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http://salestores.com/lacros111.html
Speaking of measuring airflow I thought that flowing paint trick mentioned in the article was a nice idea. I like it because it is cheap, easy, and can be used on just about any surface on the car. I wish they had described the recipe in more detail (x parts of paint, x parts of 3-in-1 oil, x parts of alcohol). But it should be not too hard to figure out with some searching and/or trial and error.
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