coefficient drag
 

What is the co-efficient drag of the fd in stock form? Can anyone tell me which body-kit will further enhance the aerodynamacy(sp?) of the fd3s?


Ok, now for the crazy question. Now dont hate on me cause i'am a supra owner:D I know anything is possible, but has anyone thought about or have done a targa top conversion on a fd?? Would this make sense or would the car rip itself apart cause of its light weight? I'd hit it!! :D

ALL opinions wanted...flame suit is on!

I've always wondered the COD of stock trim with lights up and down.

According to THE MAZDA RX-7: Mazda's Legendary Sports Car by Jack Yamaguchi, the FD's Cd is 0.31

The lower the number the better, right? I keep forgetting.

Any thoughts on the targa idea??

yup lower the better.

its .31 with spoiler, .29 without i am pretty sure.
i remember reading a thread a waaays back stating that the stock spoiler does shit. and a targa top has been done i believe, with a crossmember down the middle. it really weakens the rigidity of the car. there have been threads about it. no more triangle(side view) along the edges of the roof = bad idea.

To this day not many cars have gotten that low. Except for Corvettes, Vipers, Porsche until recently. The FD had one of the lowest coefficient at the time for a prodcuction car.

-HeX

Ive seen the stock spoiler hold up to about 215.. im sure im not the only one that has seen this. But if i was planing on doing anything near that i would get a real spoiler. I heard the drag was .28 but what do i know. anything in that range is sick and wrong. I think the new NSX got a better drag and is now at .30, and if the 7 is better than that, good deal.

My 90 CRX was .29 :)

most aero kits will reduce the coefficient of drag if they are functional and provide downforce. Practically all wings hamper the CD.

If you want to improve your CD, start with under the car, where there is the most turbulence. A rear diffuser and underbody carriage(?) should help immensely.

Lowering a car will also slightly help, as the wheels add some drag.

You planning on hitting up the salt flats or what? you wont really realize any minor CD changes until you hit speeds of 150+ in a car that already has an exceptional CD

Kool! Thanks guys, so the targa has been done...ill have to do more seraching. Maybe if i bought 2 fd's i would turn one targa, but thats already alot of money. Actualy ill be better off just paying friggin 30+k for an mkiv. So, this is what i got....lets say a hard-top fd with front and rear diffusers, tein ha with the edfc and no wing, would be the best aerodynamacy you could prolly get huh?

It's about 19.3 SQ FT frontal area.

Ken

These couldn't have been more wrong. You're mistaken Cd with total drag, lift, and downforce.
A rear diffuser and underbody carriage help reduce lift in that it speeds up the air. The faster the air travels, the less pressure it is(Bernoulli eq.). See to the function of a wing in an airplane, it's very similar. It sure will help Cd, but not greatly.
Lowering the car will not help Cd, however it will help reduce total drag. It's because total drag is associated with Cd multiply with frontal area. A skinny car with high Cd might have the same drag resistance as a fat ass car with low Cd given the same height.
And most functional aero kits don't help reduce drag, but they do provide higher downforce, which is more beneficial in most cases since the car will be more balanced and has more grip in fast turns.

FYI, the new Lexus LS and MB S-class has better Cd than 0.29. I think the Lexus stands at 0.26 and the MB at 0.28. You wouldn't think so heh ? The most important thing in reducing drag is keeping the air separation minimal, very hard to explain in words. Go pick up a book in fluid mechanics or take fluid mechanics class in college, you'll understand.

.29 no spoiler no lip, r1 .31

Yeah, usually spoilers increase drag and downforce. Not sure if the stock rear spoiler adds any downforce though. However, the front R1 spoiler does reduce turbulance under the car.

hmm...interesting, thanks!

What exactly is a "real spoiler" Aluminum:confused: :D

^ this man needs serious education..........i hope he doenst have a FD:confused: :(

Please read and comprehend what you are reading....it was a JOKE there guy...

Remeber, when comparing cd amoung cars that the total drag is the cd * (frontal area)^2. So a car larger than an FD with lower cd will probably still have more drag. And a smaller car with a higher CD may have less drag.
Also, a rear spoiler that is wide enough to add the frontal area is never going to reduce drag.

If you want to do a targa top conv. stick with the Supra, Please.

so drag is in units of area^2 ?

how about this? Total Drag = (Cd*frontal area*1/2*air density*air velocity^2) + whatever induced drag you get. Thats comes out in units of force at least.

i know(in the other thread that had a big thing about this whole Cd topic) that the stock rear spoiler is non functional just adds drag/looks.

Hmm..what about the 99' spec body? Is there a difference in cd than 93'-95's?

Does the 99' spec wing work? lol..;)