Front end 'spook' options..

[CDM]

I very seldom get time to reply but I thought this may be a good chance to let you all know about some new stuff we have been working on for your Z cars. To keep the guys who race from ruining the 3 lower front chin pieces I have recently finished a high quality 1 piece replacement that fits the same and can be used on a street car as well as a vintage race car. It is so fresh we have not even finished the block off plates for the Turn signal lights yet. I believe this piece would be a cheaper alternative to the original 3 pieces if you cannot find some for a reasonable price. The other Long awaited new part is the Series 1 rear hatch panel which like all our plastic replacment panels will come in the various colors. Now this new piece is also so new I have not experimented with adding all the internal vent parts so I will post photos of the new hatch piece tommorrow on our site and you can presently see the one piece chin with the correct BRE spoiler in our 240Z section at www.classicdatsun.com Thanks.

Les

[26th-Z]

Nice car Zedy; I like the clear signal lenses on silver. But she does have a bit of a chin on her? When we talk about front spoilers, I always like to throw in these pictures. We'v talked about this before - somewhere buried in the library.

The BRE type is very common but the questions raised about mounting it and stability are valid. Just ask Carl what happens to those metal valance panels when you whack on the spook! :eek:

Nissan did make a front chin spoiler however it was not imported. The need for downforce was recognized by Nissan. This "urethane / foam" flexible type spook mounted to valence panels that came with captive nuts.

And this is what it looks like....

[26th-Z]

Whoops! Wrong picture

[geezer]

For a street driven car I really liked this fiberglass 1 piece that retains the turn signal openings. I was considering glassing my spook to it, in order to create a 1 piece rigid assembly, but when this was on Ebay recently, I didn't bid high enough. It sold for $220.00 I believe.

[Carl Beck]

True that, I never did like those add on Airdams.

It may may true they increase down force so don't get me wrong, but they

do as you said completly throw off the intended style of the car as a

sleek aerodynamic sports car.

Infact I'm willing to bet those alos increase wind drag :ninja:

Over the years, most of the "tests" that have been conducted seem to agree in general terms, if not in specific pounds of force.

1. The shape of the Classic Z's is not considered to be very "aerodynamic" in stock form.

2. The OEM Front spoiler (see Chris's post) - had very little effect.

3. The air dams - direct air around the sides of car, and reduce air flow under the car. So the do reduce drag. They also reduce "lift", but do not generate much additional down-force. Because they reduce "lift", the do add to the stability of car at 40mph+

4. The BRE Style Spook's reduce drag and generate a great deal of down-force because they redirect the air flow up over the hood as well as around the sides of the car. The non-ducted version is more effective than the ducted version at increasing down-force. The Spook is very effective at keeping the front tires on the road at speed (reduce lift and increase down-force), and you can really feel the difference.

From personal experience - the Spooks won't damage the lower panels in minor run in's with parking stops - but in a front end crunch.. it turns out that the Spook is stronger than the sheet-metal. So it will damage the sheet metal if you hit the Spook hard enough to tear it off the car.

FWIW,

Carl B.

[Arne]

The addition of my ducted spook made a profound improvement in the car's stability at even low highway speeds - even 50-60 MPH. The improvement at 70+ is simply amazing. Crosswinds and passing trucks no longer bother the car. Probably the best single thing I did for the car.

[psdenno]

The addition of my ducted spook made a profound improvement in the car's stability at even low highway speeds - even 50-60 MPH. The improvement at 70+ is simply amazing. Crosswinds and passing trucks no longer bother the car. Probably the best single thing I did for the car.

In addition to all of those handling improvements, mine made a fairly good unintentional snow plow from time to time when I was living in Topeka in the early 70s. It only broke once when I hit a huge drift one dark and stormy night.

Dennis

[doradox]

4. The BRE Style Spook's reduce drag and generate a great deal of down-force because they redirect the air flow up over the hood as well as around the sides of the car. The non-ducted version is more effective than the ducted version at increasing down-force. The Spook is very effective at keeping the front tires on the road at speed (reduce lift and increase down-force), and you can really feel the difference.

FWIW,

Carl B.

IIRC the MSA airdam outperformed the BRE style chin spoiler in the HybridZ windtunnel tests with much reduced drag. However front end downforce within about 5 lbs or so, advantage to the BRE spoiler. I'm not sure if that was an apples to apples comparison though.

Steve

[Arne]

A good air dam should reduce drag, as they get the tires out of the air stream. But a spook still looks better on a 240Z to me...

[Carl Beck]

IIRC the MSA airdam outperformed the BRE style chin spoiler in the HybridZ windtunnel tests with much reduced drag. However front end downforce within about 5 lbs or so, advantage to the BRE spoiler. I'm not sure if that was an apples to apples comparison though.

Hi Steve:

If you compare test #9 (add BRE Spook) directly to test #16 (add MSA air dam).... it's not apples to apples.

On the other hand if you take test #9 and make all the enhancement from tests #10 thru #15, then compare that to test #16 (where only the front air dam was change to replace the BRE Spook), you can get a little closer to apples to apples.

<pre>

In that case.

Stock 240Z #19 CLF = 304 lbs of lift = 207.279 lbs of drag = 309.402

BRE Spook #15 CLF = 212 lbs of lift = 144.000 lbs of drag = 280.954

MSA A/D #16 CLF = 287 lbs of lift = 195.554 lbs of drag = 300.050

</pre>

So test #15 with the BRE Spook and all other enhancements, to test #16 with all other enhancements only with the MSA air dam changed - you increased lift by 50 lbs and increased drag by 20 lbs.

But I agree - it is hard to get real apples to apples, when so many other chagnes were made that could effect the specific performance of either part.

FWIW,

Carl B.

[ChrisZ]

Zedy, i just noticed both a valance and two corners at ebay, just passing it on.

Chris

[doradox]

Hi Steve:

If you compare test #9 (add BRE Spook) directly to test #16 (add MSA air dam).... it's not apples to apples.

On the other hand if you take test #9 and make all the enhancement from tests #10 thru #15, then compare that to test #16 (where only the front air dam was change to replace the BRE Spook), you can get a little closer to apples to apples.

<pre>

In that case.

Stock 240Z #19 CLF = 304 lbs of lift = 207.279 lbs of drag = 309.402

BRE Spook #15 CLF = 212 lbs of lift = 144.000 lbs of drag = 280.954

MSA A/D #16 CLF = 287 lbs of lift = 195.554 lbs of drag = 300.050

</pre>

So test #15 with the BRE Spook and all other enhancements, to test #16 with all other enhancements only with the MSA air dam changed - you increased lift by 50 lbs and increased drag by 20 lbs.

But I agree - it is hard to get real apples to apples, when so many other chagnes were made that could effect the specific performance of either part.

FWIW,

Carl B.

Yes. I see. I didn't realize that they were adding components each time. Lots of variables especially considering the different way an airdam and chin spoiler route air over/around the car.

I have a question though about the Cl. It's defined on the site as..

C LF front lift neg # = lift, pos# = down force on front end

C LR rear lift neg # = lift, pos # = down force on rear end

which seems backwards to me since the BRE spoiler had the lowest Cl and the lowest lift. By definition Cl is Lift/(roughly the velocity and density of the fluid, and area of the wing) so a higher Cl would be higher lift/less downforce.

Am I missing something?

Steve