You didn't say stock, but if you consider a intake not stock whatever. We all know intakes don't do jack.

 

That;s not mine, I had a bad night when I went and sucked. I only got a 13.9 out of mine. Plan to go when its cooler, but since I don't have stock tires anymore guess I am not stock.

 

But since nobody actually knows how much downforce is being applied at top speed and how much drag is actually being created, nobody knows how much slower it actually is, thats what i'm saying. Are we talking like 10,15,20mph+ slower? nobody knows, becuase i'm pretty sure this has never been tested. We just know thats it's slower.

 

It's all physics. Do the math. The total downforce on the Nismo at 160 mph is 255 pounds.

 

At this point, for anyone serious about buying the 'best performing Z' for the money it would probably be best to wait and see what the 370's stats will be like.

 

sweet, theres too many variables to actually figure it out, some of which we do not know.

 

Coefficient of drag is 0.33 for the NISMO and .29 for the GT

EDIT: I believe the regular Z doesn't have any downforce at speed, in fact I believe it does the opposite...

 

i can settle this debate.................i have a nismo so it must be better dammit.

 

 

Wrong. All you need is the coefficient of downforce which is .0027 for the Nismo and the density of air which is 1.2929 kg*m^-3 at sea level.

Fd (downforce) = velocity^2 * Cd * 0.5 * Da

The only unknown would be winds, this assumes no wind.

EDIT: I forgot to add, velocity will need to be in Kilometers per hour and the downforce will be in Kilograms. You will need to convert afterwards if you want to see Pounds of downforce.

mph * 1.609344 = kph
kg/.45359237 = lbs

 

What is the suorce of your coefficient of downforce?

 

windtunnel testing with scales....

 

i live in davie fl and got it from lehman subaru on 441 and countyline

 

Windtunnel testing on scales? Was this info from Nissan on the Nismo? Something done by someone else on the Nismo? or just a generic number?

 

so......

 

Its all personal preference and taste. Pick the right Z for your taste.
Why I did not get the NISMO:
1. I am no longer into body kits.
2. The rear wheels are freaking heavy. Needless unsprung weight, The s-tune 19 inch wheels are much lighter.
3. No longer into driving stick shift, I have had a g35 sport coupe with the brembos, and I just have to say I was not happy with the manual gearbox, compared to the corvette or mustang manuals I have driven.
4.the body kit stands out too much for me
5. should have used the S-tune exhaust with custom tips, and then it would have more horsepower.
6. suspension should be lower. In person the NISMO looks like it sits higher than stock.

And for those who are still not sure. The NISMO does not use the S-tune parts. The NISMO uses specially engineered parts.

Of course the NISMO has the best skidpad numbers of all the Z's. But it not that much better than the s-tune set up. I wonder how much of an improvement an S-tune would see on the skidpad with the front and rear dampers, that are standard on the NISMO. and of course the NISMO has a welded chasis.

 

So what? You said it wasn't possible to figure the downforce and I showed you that it was.

I'm glad that you asked. I was quoting information from an old post of mine. My old source said the downforce on the Nismo was 55 pounds at 75 mph, I used this information to calculate the coefficient of downforce. I discovered that the information was incorrect. But, simply reorder the equation like this to figure the coefficient (Cd) when you know the velocity (v) and downforce (Fd) at the given velocity:

Cd = Fd * 2 / (v^2 * Da)

All of the information I can find states that the downforce is actually 11 pounds in the front and 33 pounds in the back at 73 mph (a few links at bottom). That means 44 pounds at 73 mph, total (Yes, you can add it together, it will net the same total result).

.00224 = 19.96 * 2 / (117.5^2 * 1.2929)

So the coefficient of downforce is actually .00224, not .0027. That means the downforce at 160 mph is actually...

Fd = v^2 * Cd * 0.5 * Da

96 = 257.5^2 * 0.00224 * 0.5 * 1.2929

96kg / .45359237 = 211.6 lbs.

If you try this yourself, don't forget to convert MPH to KPH and Pounds to Kilograms beforehand!

http://grassrootsmotorsports.com/new...an-nismo-350z/

http://www.caranddriver.com/reviews/...take_road_test (only mentions the rear end downforce)

If you can find more accurate information, post it here so I can see it...

 

The Nissan Sport Magazine article on Wind Tunnel Testing mentions 20 lbs downforce on the front, and 50 lbs on the rear at 70 mph (Fall 2007 pg 77). They didn't test this, but I think I saw on a post somewhere that they got this from Nissan. I have been wondering if Nissan had published actual data somewhere.

 

I haven't be able to find anything published directly from Nissan about this, but I haven't spent a great deal of time looking either. My old source was car and driver as well, but I guess they removed the page because the link only takes you to the home page now, not the original page. The new page on the Nismo has conflicting data which is why I figure the old data was incorrect.

I've even seen conflicting data on the drag coefficient. I've seen .30, .31, and .34 (.339). I tend to believe .34. There simply isn't any way the Nismo can produce that kind of downforce while still having the same drag coefficient as a regular Z (which has lift, not downforce).

 

So you're telling me that if you had 1200 lbs of lift in the front and 1500 lbs of downforce in the rear, you'd have 300 net pounds of downforce?

Something tells me that it doesn't quite work that way. Maybe for small numbers, or if there is downforce on both sides.

If you have any experience with windtunnel testing, you'd know that vehicle squat, downforce, and speed are the three major factors.

A vehicle may have lift at a given speed, while having downforce at an other speed.

Your formula only works for a car that has a perfectly rigid suspension, and does NOT apply to cars in real life.