Does anyone have information on downforce and drag for a Zed with a factory spoiler vs brazillian? Just working out which way I want to go with the track car. 2 seater ideally.
I would think that there would be no difference between the two. Stock spoiler is more of an asthetic wing as opposed to a functional wing. There would be slightly more turbulence off the lip of a stock wing but it would be too small to measure IMO. A functional wing needs to be raised off the body so that air can go above an below it to create downforce.
I have heard somewhere that the stock wing was quite carefully designed to produce a decent amount of turbulence so you are not dragging a huge chunk of air behind you at speed and because of this it makes a reasonable difference to economy and performance at higher speeds. I can't remember where I heard it and as such have no idea how reliable it is though, hence asking here.
I read somewhere years ago that the drag was reduced with the spoiler removed. No idea by how much and if it was at all reliable.
See, that's the opposite of what I heard, I've got no idea if my information was reliable either though. My concern is over all performance so both need to be considered.
Get a nice big wing if you're worried about down force mate, I would definitely be doing that on a track car along with a rear deiffuser and front splitter.
I wouldn't think that at sub 200kph speeds the difference between the two would not be noticeable. The zeds body shape does most of the drag reduction. Im happy to be proved wrong. If I was building the track car. Id get rid of the heavy stock wing (-10kg) and go brazillian. I would then get and adjustable race wing so that you can find a suitable balance between downforce and drag. I'd then get ztoy to build you a composite hatch to remove a heap of weight.
From the book "300ZX Enthusiast's Companion". pages 16-17. Brazilians are faster. Were all factory Brazilians NA ?
Yeah, if the regulations allow it there will definitely be a wing happening. I heard that above 100km/h the reduction in drag from a stock wing is noticeable. Again, no idea if this is accurate or not. If I keep teh stock spoiler it will be fibreglass too, as you said, the factory one is too heavy. If I'm allowed to for the MSCA here I'll be getting a wing too.
More quotes: Do not know where the sheep shaggers lifted this quote. http://www.300zx.net.nz/articles/300zx/body1.htm This is for teh Z31, where the effect seems to be a reversal. http://auto.howstuffworks.com/nissan-z-history5.htm
Thanks! This is going to be a track only car so I've got a pretty high tollerance for ugly if is gets me going faster. Also, no way I'd use the actual stock spoiler but is it has significant aero advantages I'll be making a lighter fibreglass copy.
the stocker will make downforce but only a tad and if you go fast enough. a ugly GT wing (even a cheapie) will actually do a better job and TBH, on a track car that's the only thing you should run. removing the stock wing will save weight and combined with slightly less drag give you better fuel economy but that's obviously last on your list of concerns to sum up, bin the stocker, it's of no use.
Fuel ecconomy as such is obviously not a concern but if it's slippery enough to get improved fuel ecconomy it shoudl also get more straight line speed for the same power too. If the MSCA regulations allow it I'll definitely be putting on a wing too.
you can't have both though. a big wing will give you downforce but it causes drag. no wing is more slippery and might give you a bit more speed on a straight but in high speed corners you'll want to have the big GT wing. i guess the stock wing is meant to be a compromise, if you were going fast enough, it'll make a bit of a difference. for a street car it really doesn't need to be there since you're only going in a straight line at those speeds on the street (and enough to get into a lot of trouble with the popo). for the other 90% of the time you'd want the fuel economy.
I was under the impression that the stock wing broke up the air behind the car so reduced the amount being dragged along behind you and hence the improved ecconomy/straight line speed. I know any wing or spoiler that generates useful downforce will cause drag, the force has to come from somewhere after all. No free lunches here.
No such thing as a free lunch really. The Nissan wing isn't a miracle worker. No doubt it's very good. For what's mainly a aesthetic wing, it keeps the drag to a minimum but will offer a bit more downforce if someone was pushing a TT hard enough. I'd say for the European market and to some degree the American market, it was necessary. For our rubbish roads and nanny state levels of speed control, it's completely unecessary to have. For track work, just go aftermarket. A GT wing with angle adjustments will give a bit more flexibility. For a slow track where the NA barely sees third like haunted hills, give it plenty of angle or maybe just leave it off. On a track like Sandown you'll definitely want to have it but probably less angle so it doesn't slow you down too much on the long straight but at the end of it, you're still gonna have more grip than you would with the stocker.
Yeah, I was fairly sure there was no real downforce from the stock wing, I'd heard somewhere it was OK at reducing the lump of air you're dragging behind you though. Seems like it doesn't do much of that either. At least that will make moulding a fibreglass hatch much simpler.
they were in the US. That article that mentions the design was basically referring to US models since Jspecs all came with stock wing until much later. I see some late 98-00 models which are factory brazillians. http://www.goo-net.com/usedcar/spread/goo/19/0160110601G4000682008.html http://www.goo-net.com/usedcar/spread/goo/17/700102046520110429003.html
