Wind tunnel testing on the S30

[datsun40146]

Members at hybridz including myself are putting togther donations to take the S30 to a wind tunnel I thought I would let the fellas here at classiczcars know. BJ Hines and a few others from the North Carolina area have gotten together with the owner of a windtunnel and are planning to rent the windtunnel for some basic testing/ data collection on the Zcar, both in stock trim, and with a number of spoilers/airdams/aerodynamic devices to see what really helps, what really doesn't and what cause and effect can be measured.

This is VERY important to each and every one of you who drives an S30. We all thumb thru the pages of each vendor catalog, trying to decide which air dam looks best, or which rear wing provides the most function along with form. Don't you want to know WHAT TRULY WORKS? After this testeing is done will be be able to finally end the debate on what works and what doesnt. All the information gathered from this will be free and open to the public, it will be posted on hybridz.org in the form of video, pictures, and graphical information from the wind tunnel. here is the link to the thread on hybridz http://forums.hybridz.org/showthread.php?t=116938

[BRE-240Z]

That should be interesting.

I was reading an article the other day in Motor Trend Classic, and a sidebar said that the C3 Corvette was actually supposed to make its' debut in 1967 instead of 1968, but that they pushed it back a year so that they could remedy some problems with 'dangerous lift' and horrendous drag at high speeds.

My first thought was 'Ah, so it wasn't just the S30! Other cars also wanted to go airborne!' -- ha.

Thanks for the link.

[hls30.com]

Are you guys aware that Nissan listed the Cd for the S30 as .467, Clf as .41 and Cmy as .10 on page 17 in the Datsun 280ZX book they sent to 280ZX owners, and Don Sherman wrote a five page article in the May 1974 issue of Car and Driver (pages 39-43) detailing what to do about the shortcomings with airdams, wings and the like.

I am not saying don't do it. I am saying look at what was done and make sure you add to instead of just duplicate the results...

Will

[Arne]

I remember that Car and Driver article from reading it while I was in high school. I wish I knew where I could find a copy of it now, it would be interesting reading for those of us who want to keep their cars looking "period-correct".

[hls30.com]

I'll see about getting a new scanner in the next couple of days, and taking care of that. Two year olds and thin scanners don't mix!

Will

[xray]

Seems to me a good way to determine HOW MUCH benefit a particular style airdam/spoiler has in affecting drag and lift. We all know the shortcomings, but the data is lacking. One can proclaim this or that effect all he/she wants, but now's a chance to find out QUANTITATIVELY what works better or worse or not at all.

http://zccw.org/Tech/Body/early_aero.asp

Nice article giving a tour of stock-configured 240Z aero issues, but with a palpable dearth of hard data. Would be nice to know if BRE's spoiler does a better job than MSA type 1,2 or 3, especially for racers. Why shoot in the dark with a bunch of choices that probably look better than they actually perform? Waste of time and money trying to find the right one....And here's the kicker: once you have data, you set the foundation for improvement and innovation, possibly resulting in a better product for racing/safety applications...

Will, not many of us have the 1974 issues of C&D, perhaps you could scan and post the relevant discussion so as to better establish baselines? As for the 280ZX, it appears no S130s will be used during this testing.

Being local to this event (Triangle Z Club) I plan on providing support where I can. I hope others would be interested too....

Steve

[26th-Z]

Ben Millspaugh wrote a wonderful article about aerodynamics in the March / April and Summer 1995 issues of Z Car magazine. As much as I admire the effort going on over at HybridZ, and I will keep up with their reports, I don't suspect much new ground will be broken. In my opinion, it is going to be difficult to beat the stock Nissan front spook and rear spoiler - ala BRE to us "Mericns" call them. Should be an interesting project.

[Carl Beck]

I remember that Car and Driver article from reading it while I was in high school. I wish I knew where I could find a copy of it now, it would be interesting reading for those of us who want to keep their cars looking "period-correct".

Hi Arne:

You can find a copy on the Z Car Home Page:

<a href=http://zhome.com/ZAerodynamics/AeroMillspaughPart1.htm TARGET=NEW> AERODYNAMICS by Ben Millspaugh </A>

FWIW,

Carl B.

[Craig Lovegrove]

That sounds like an awesome project. I would love to see the results. I have always wondered what the stats might be and what would work best.

[Carl Beck]

....snipped...

In my opinion, it is going to be difficult to beat the stock Nissan front spook and rear spoiler - ala BRE to us "Mericns" call them. Should be an interesting project.

Hi Chris:

Us "Mericans" don't call the BRE Spook - "stock"!!

Actually, according to the Car & Driver Tests - it was quite easy to beat the "stock" Nissan equipped car.

Car & Driver said Nissan's front chin "spoiler" was so small as to be all but worthless. Adding the OEM rear spoiler then made the situation worse, as it put significant down force on the rear, and thus caused farther lift on the front.

The BRE "Spook" (Spoiler and Scoop) put things back in balance, by adding significant down force on the front - that in turn worked well with the Nissan/BRE rear spoiler. The added benefit of the Spook was additional air directed into the radiator, with ducts for better brake cooling.

FWIW,

Carl B.

[VaGuS510]

How much is this going to cost? Have you looked into CFD (I believe that is what it is called), computational fluid dynamics. It is a form of finite element analisys that can compute everything that you could compute in a wind tunnel and even more probably. The only thing is that you would need to do is pay someone to create a model of the S30 in the program and test it. I would look into this because a CFD can give you much more data in much less time.

Just my two cents.

[hls30.com]

Carl gave the Readers Digest version of the article, here are the numbers to go with:

Stock trim baseline @70mph 140lbs lift at front end, 20lbs lift at the rear

With only a Datsun Competiton parts offering (3.5" deep) and you are at 105 lbs lift at the front end and no gas savings

With a vented Spook and you are at 35lbs lift at the front end and 35 lbs lift at the rear adding .4mpg to fuel economy.

cover the vents(or use the non vented version) and you at at 25lbs lift at the front with no change at the rear.

Use an 8" verticle airdam 48" wide and v shaped and you are at 65 lbs lift at the front end and 30lbs lift at the rear with .8 mpg added fuel economy

With only an interpart rear spoiler you have 55lbs of down force at the rear while improving fuel economy .2mpg

Headlight covers do not affect down force, but do add .2 mpg to fuel economy.

With the spook, sealing the bumper to the hood with a cardboard panel gave a .8mpg gain in fuel economy.

Adding a gnose with headlight covers and get 1.2mpg and 5mph top speed.

I will see about posting the graphs when I can.

Will