aerodynamics question
Drifting
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From: Berlin
Originally Posted by corvette-pilot
I have to see if I still have an old issue of Corvette Mag from a couple months back. It was the one picking the influential cars of that era. I think they picked the 78 pace car. Funny thing that sticks in my mind was they refered to it as a brick. That modern sedans are more aero. I think the article mentiond some numbers.
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From: Reno Nevada
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Bonneville Salt Flats C-3's
As soon as I can figure out how to retrieve and post pictures out of my CF home page I will post them
Those guys told me that the big thing is rake of the car. Lowering the front makes the front end very stable at over 200 mph. I did the home scientific testing. While driving in the rain at 80 mph I noticed that my stock 79 had still air from windshield high pressure zone allowing water to bead up on my hood and sit still nearly half way out.
Once I put on 1 inch shorter 550# front spring and shorter lower profile tires this reversion zone on my hood had moved back to within 8 - 12 inches of the windshield. I also added a larger chin spoiler to keep even more air out from under my 79 and that's when I first started driving it at @175 mph during testing and racing in Nevada open road races. I later installed the 81 Daytona front end that was made for racing at over 200 mph in the twin turbo Vettes.
Those guys told me that the big thing is rake of the car. Lowering the front makes the front end very stable at over 200 mph. I did the home scientific testing. While driving in the rain at 80 mph I noticed that my stock 79 had still air from windshield high pressure zone allowing water to bead up on my hood and sit still nearly half way out.
Once I put on 1 inch shorter 550# front spring and shorter lower profile tires this reversion zone on my hood had moved back to within 8 - 12 inches of the windshield. I also added a larger chin spoiler to keep even more air out from under my 79 and that's when I first started driving it at @175 mph during testing and racing in Nevada open road races. I later installed the 81 Daytona front end that was made for racing at over 200 mph in the twin turbo Vettes.
Last edited by gkull; Jul 13, 2004 at 11:31 PM.
Racer
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From: Iowa
This is an interesting thread.
Can anyone tell me more about the "Daytona front". I am interested in changing the front end on my 77 for an aerodynamic gain.
The rubber front is beat up and the car need to be repainted so I have been considering options to modify the front such as glassing on my own design. I even looked at the race vette pictured in the Mid America Motorworks catalog in the suspension section. It looks like the rubber front was removed and a little glass work was done along with a custom grill and spoiler. Anyone know about this car?
Can anyone tell me more about the "Daytona front". I am interested in changing the front end on my 77 for an aerodynamic gain.
The rubber front is beat up and the car need to be repainted so I have been considering options to modify the front such as glassing on my own design. I even looked at the race vette pictured in the Mid America Motorworks catalog in the suspension section. It looks like the rubber front was removed and a little glass work was done along with a custom grill and spoiler. Anyone know about this car?
Drifting
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From: Berlin
Originally Posted by gkull
Those guys told me that the big thing is rake of the car.
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Originally Posted by aharte
Sedans usually have better drag coefficients than sports cars. I have a sedan from 86 that looks like a brick, but has the same drag coefficient as a C5 vert. There are now several which are much better than C5 or even C6 coupes.
Drifting
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From: Berlin
Originally Posted by ddecart
You'll have to back that up with data for me to believe it. I doubt there are any 1986 cars that come anywhere close to C5/C6 aero numbers.
http://www.bentleypublishers.com/gal...l=&ticket=none
That book I quoted above says that an Opel Kadett GSi, Renault 25 TS, and Audi 100 1.8 all had 0.30-0.31 coefficients in the early 80's.
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Opel Kadett ain't no sedan, it's a hatchback, first of all it's a POS car 
and it's kind of streamlined. The GSI has all kinds of spoilers and stuff on it from the factory:
this one has some modifications on it but basically all that stuff is on the factory model too...just a little less tacky
and it's kind of streamlined. The GSI has all kinds of spoilers and stuff on it from the factory:this one has some modifications on it but basically all that stuff is on the factory model too...just a little less tacky
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From: CORVETTE 77 385 C.I. TEXAS
Originally Posted by jetech
This is an interesting thread.
I am interested in changing the front end on my 77 for an aerodynamic gain.
I am interested in changing the front end on my 77 for an aerodynamic gain.
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From: Reno Nevada
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Jetech
Something what Ganey did is the best idea. The whole Daytona front end is replacing all the body from the firewall forward. The cost is substantial with lots of custom fabrication
The loss of @ 150 lbs due to the thinner fiberglass construction, off the front end really helps make our old C-3's when combined with good tires and suspension parts into a real road race machine.
The loss of @ 150 lbs due to the thinner fiberglass construction, off the front end really helps make our old C-3's when combined with good tires and suspension parts into a real road race machine.
Racer
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From: cincinnati oh
I would like to see the drag info for these cars also. At the time the C5 was put into production it had the lowest cd of any car. I have a microphone array and a sonic digitizer if anybody wanta to measure to area of their vette!
Racer
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From: cincinnati oh
It uses three mics placed a known distance apart (50.931") and two signal generators that are 1 foot apart. The noise is generated and the three mics pick up the sound and calculate how far that point is from the center of the mics. You hold the signal generators against different points on the surface and it maps the distance for you down to about .0005". All the car companies use this method to "draw" a realistic picture of the car in the computer. They use this to calculate airflow and whatever else. Here is a link if you want to check it out:
http://www.modalshop.com/resource/pd...%20reprint.pdf
http://www.modalshop.com/resource/pd...%20reprint.pdf
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Originally Posted by aharte
This is what google turned up. It gives a drag coefficient of 0.31, which is what I remember from somewhere else also. Scroll down to the "body exterior" section.
http://www.bentleypublishers.com/gal...l=&ticket=none
That book I quoted above says that an Opel Kadett GSi, Renault 25 TS, and Audi 100 1.8 all had 0.30-0.31 coefficients in the early 80's.
http://www.bentleypublishers.com/gal...l=&ticket=none
That book I quoted above says that an Opel Kadett GSi, Renault 25 TS, and Audi 100 1.8 all had 0.30-0.31 coefficients in the early 80's.
Drifting
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From: Berlin
Originally Posted by ddecart
The C3 is 0.29 according to 'official' published numbers.
What does that mean? I've never heard any numbers nearly that low.You seem to be saying that the manufacturers are lying. If that's the case, then what would you believe? And why do you believe the C5 marketing?
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From: All humans are vermin in the eyes of Guru VA
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Originally Posted by ddecart
The C3 is 0.29 according to 'official' published numbers.
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Originally Posted by aharte
What does that mean? I've never heard any numbers nearly that low.You seem to be saying that the manufacturers are lying. If that's the case, then what would you believe? And why do you believe the C5 marketing?
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Originally Posted by Guru_4_hire
If its that low then why is the C3 regarded as the least aerodynamic corvette ever?
Cuz it's a horrible design for aerodynamics. I'm not sure that it's worse than a Solid axle or midyear, but the back half of a C3 is horribly shaped for aero. Incidentally, the back half of a car is more important for aero than the front. And a C3, with the straight rear window, and the large 'square' area behind the car, isn't real slick (pun intended).
drag = Cd x A x p x FluidsClassWasTooLongAgo
As you know, Cd is only half of the story. CdA is what really defines the aero-drag of a given vehicle. You could have a Mack Truck with a 0.12 Cd, but with an A the size of a house, it's still going to have a boatload of drag.
Some good reading on aero is...damn...can't think of it. But its the story of the Daytona Cobra and how the guy that designed it basically went against popular theory and it turned out the design worked well.
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From: All humans are vermin in the eyes of Guru VA
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So is there a means to reshaping the area around the rear window to make it more aero dynamic?
I dont know maybe like a lip of some kind?
I dont know maybe like a lip of some kind?