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Clever, don't you have a bar examine to study for? I've owned and restored more Vettes than you'll ever come close to. You've riced out 1 C4 so far. Get over yourself......
Now go think of another snappy comeback laced with rambling rants.
Clever, don't you have a bar examine to study for? I've owned and restored more Vettes than you'll ever come close to. You've riced out 1 C4 so far. Get over yourself......
Now go think of another snappy comeback laced with rambling rants.
Last edited by uptown193; Sep 2, 2010 at 02:33 AM.
I agree that it doesn't reduce drag... but with the center piece out of my car it ran about 10 degrees hotter water temps and 20 degrees hotter oil temps (I have an oil cooler up there too) on the same day with the same conditions. Look at the factory air dam... at the angle that it comes down it has pretty much eliminated laminar flow up into the radiator on its own. Just judging by my eyeball engineering I don't think that the Greenwood nose necessarily improves laminar flow but I think that it most definitely forces more air up into the radiator "cavity".
I also noticed a huge difference at speed in how planted the nose was with the center piece in place as compared to it out. If you look at the pic of the car at speed (~130 mph)you can see how far it pushed down... aka downforce. For reference, I weigh about 200 lbs and it doesn't push down that far with me standing on it. On top of that, I guarantee that the hood louvers add quite a bit of downforce at speed. I had an oil leak at one point that created smoke under the hood that vented out through those louvers. The flow across and out of them was almost perfectly laminar and was pretty clearly a "downforce" flow.
Long story short is from my own experience...
downforce - yes.
help cooling - yes.
reduce drag - nope.
I don't have a problem with what you are saying. My post was primarily to note that there is no free lunch. From an engineering standpoint there are always trade-offs.
As for the cooling thing, I can buy that there is a certain amount of air channeling that aids cooling, but also at a significant further hit to drag.
I don't have a problem with what you are saying. My post was primarily to note that there is no free lunch. From an engineering standpoint there are always trade-offs.
As for the cooling thing, I can buy that there is a certain amount of air channeling that aids cooling, but also at a significant further hit to drag.
There are trade offs for sure. The downforce aspect of course adds drag .That is simple aerodynamics but I don't agree about the significant further hit to drag in regards to the direction of cooling air in this case. When you look at the stock design you have what is basically a 90 degree wall formed by the stock air dam. Rather than directing air flow it seems to me like it simply creates a big high pressure area (i.e.. lots of drag) that forces air up into the bottom and through the radiator. At speed the stock air dam has a tendency to bend down which would actually direct air downward and produce lift (not a good thing). With the leading wing out there, it looks to me like it actually creates a laminar flow all to the way to the radiator, and both the upper and lower surfaces direct air up and around the stock dam as illustrated in the drawing and would direct a good portion of that air into the radiator cavity without hitting that huge cd stock air dam.
I know that what I have said is just my eyeball engineering and to really know the truth you would have to have a lot of money and a wind tunnel but I wouldn't be surprised if the Greenwood nose actually does reduce overall drag when you consider the amount of drag reduction by eliminating most of the front air dam and the removal of that huge high pressure area caused by it. It has been documented in the past that C4 noses have a tendency to get light at high speeds. The cause of that is that high pressure pocket under the nose that essentially pushes the nose of the car up (since obviously the ground can't go down). It also significantly reduces the amount of air flowing under the car as a whole by lowering the level of the nose. Essentially it takes less air, and flows it more efficiently into the radiator.
I don't usually but into the hype put out by a company about how well it's products perform but I do think that Greenwood most likely knows what they are doing when it comes to aero. They have been doing it since the 70s and most importantly, unlike the vast majority of things out there that are developed for looks, the Greenwood parts were originally developed to improve performance on track cars and these exact same body parts were used and developed for the Bridgestone Supercar series (and performed phenomenally). I'm not the expert on this, especially with no numerical data, but I do have an aero engineering background and by appearances alone it really does look like this one could do what they claim.
Keep in mind also that I am ONLY talking about the G4R kit and not the other various Greenwood kits out there.
I apologize if my reply is hard to follow and jumps around... I wrote it in about 4 different stages between actually trying to accomplish things at work.
I apologize if my reply is hard to follow and jumps around... I wrote it in about 4 different stages between actually trying to accomplish things at work.