Front end 'spook' options..

[ConchZ]

A less noticable alternative that I briefly considered was MSA's Aero Lip. I decided to keep mine stock, because I have a complete front valance on an amazingly original car. However, if I didn't, and wanted some "spoiler" effect, without as much risk of cracking it on a curb, I'd go with the aero lip. I'm sure its better than stock, but not as good as a full air dam or spook when it comes to aerodynamics. Here's a link to some pics of a car with one installed. It appears that its a direct replacement for the stock pieces, and even accomodates the turn signals. The little lip should disturb the flow under the car a bit, which is the goal.

[doradox]

After looking at the HybridZ windtunnel tests again it looks like a more apples to apple comparison would be test 13 compared to test 16. That compares both the BRE chin spoiler and the MSA airdam without any grill blocking that was done for both in later tests and made a big difference.

BRE Spook #13 CLF = .279 lbs of lift = 233 lbs of drag = 307

MSA A/D #16 CLF = .287 lbs of lift = 195 lbs of drag = 300

Steve

[Carl Beck]

Hi Steve:

I stand corrected. If you focus too closely - these numbers start to move in the columns.

I should have read farther down - #16's note just said; " add MSA's type 111 air dam"... so I was thinking that was the only change.

Now reading #17 it does say "block off upper half of air dam". But looking at the pictures, it looks like they really blocked off the area that would have been above the bumper. Nonetheless, it looks like they did remove all other "blocking" from the BRE test at #16.

BTW - - BRE Spook #13 the CLF should be .342 {I think you show CL above which was .279}

So:

Positive Number = down-force

Negative Number = lift

As I understand it - that is because the sensors are below the wheels. So positive numbers push the car down on the sensors increasing the numbers on the gauge, where negative numbers show the car lifting off the sensors.

<pre>

BRE #13 CLF=0.342 lbs. of lift(down-force)=233 lbs of drag=307

MSA #16 CLF=0.287 lbs. of lift(down-force)=196 lbs of drag=300

The BRE Spook puts 37 lbs more down-force on the front of the car at the expense of 7 additional lbs of drag.

But look what they both do to lift/down-force on the rear wheels

BRE #13 lbs of lift rear = -43.158

MSA #16 lbs of lift rear = -54.850

</pre>

Pushing the nose of the car down - should off-load ie. raise the rear. I would guess that the BRE Spook even though it pushes the nose down farther - doesn't raise the rear as much, because it is directing more airflow over the top - and having more effect of the rear spoiler. Where the MSA air dam puts more air around the sides of the car. So less drag, but allows more lift on the rear.

At any rate - the guys at HybridZ did a great job and I hope they do another run.

FWIW,

Carl B.

Edited February 2, 2009 by Carl Beck

[Zedyone_kenobi]

As pictured here. Are you certain that they removed this on your car?

Yup Arne, behind my front air dam, its open as the sky.. (i.e. no sheet metal at all back there...)

Well at least not valance panels, have sheet metal where it is suppose to be..

Edited February 2, 2009 by Zedyone_kenobi

[Zedyone_kenobi]

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:

Call me tommorow Zedy and I'll give you the number to my friend Jaun, he has

a few Z's and may be willng to sell you a center piece and needed parts if

you need them.

I'll use my shipper to get 'em to you safe, same guys I ship the

ANSA's with :beard:

~Z~

Get a hold of your guy Wing!!! I am on the hunt for perfect condition front pieces!!!

[Zedyone_kenobi]

Aren't you running out of platelets by now?

Yeah, I bruise easily..hee hee

[Arne]

Yup Arne, behind my front air dam, its open as the sky.. (i.e. no sheet metal at all back there...)

Seems odd to me that someone would go to the trouble of cutting that center mount off the core support. Dang, that's going to complicate the job.

[Zedyone_kenobi]

Well that center support may be there, I have never seen a picture of it. Do you have a pic of it so I can go look.

Honestly, I have not looked at much in front of the radiator support..Most of my work has been behind that...So it may be there or not, I would need to go see if I knew what to look for.

[doradox]

Hi Steve:

I stand corrected. If you focus too closely - these numbers start to move in the columns.

I'm with you on that one! I think I was looking at Cl and Clf and mixed them.

I've attached an .xls from data found on

http://www.zcarpartsindex.com/index.php?title=Aerodynamics

So:

Positive Number = down-force

Negative Number = lift

As I understand it - that is because the sensors are below the wheels. So positive numbers push the car down on the sensors increasing the numbers on the gauge, where negative numbers show the car lifting off the sensors.

I was looking at it the opposite way. Positive was the amount of lift. Lower numbers = less lift, negative is actually downforce. Look at test #2 which is stock baseline. There is 312 lbs of lift on the front and 55 on the back. That would be one of the best if positive = downforce.

Regardless, the airdam and BRE spoiler are close enough that one really need not feel he has to give up any performance to get that classic Spook styling. My first '73 way back when had a BRE style chin spoiler and an IMSA 3 piece and has always been a favorite.

Steve

Z_aero.xls

[Mike B]

Well that center support may be there, I have never seen a picture of it. Do you have a pic of it so I can go look.

Yes, Arne posted two pictures of it in post #10 and they also show in your post #28.

-Mike

[JonnyRock]

Yes, Arne posted two pictures of it in post #10 and they also show in your post #28.

-Mike

These are cropped from Arne's 2 pictures.

This is the support that's welded to the radiator cross member.

Edited February 2, 2009 by JonnyRock

[geezer]

Yes, Arne posted two pictures of it in post #10 and they also show in your post #28.

-Mike

For some reason these pictures are not being displayed. I'm only getting red Xs.