GB: Fancy wide diffuser group buy

[Slickback_Ben]

Originally Posted by AriuSen

Maybe we can split shipping costs depending on where we are located
That way we will save in shipping.
The parts alone are actually 350.
I could ask him to do 300 and then we split the shipping cost.
Would be nice if everyone interested could point your location.

Because honestly for 350 for that amount of material and construction, I think it?s fairly cheap.

What you guys think?
I?m from California. Anyone else? I would be able to receive from everyone located in Cali and ship by usps which I would guess it would cost around 15 dollar?

Also from California! If I recall correctly, I locally picked up a sway bar from you a while back?

[NYmpower]

NYC

[NavZ]

This is probably a dumb q but with the angle of the diffuser so aggressive, doesn't it eliminate downforce? ie. lift the rear wheels?
As I understood it, the bottom plate is meant to smooth things out and the vertical fins are to provide stability (looking for input from aero gurus)

[Beedub]

is this functional?

[PLCZ4MC]

Im located in South Cal too "91748" Not too far away.

[Shutterspeed]

@ariusen whatever happened to the track spec diffuser.

http://www.zpost.com/forums/showthread.php?t=1339025

[AriuSen]

Originally Posted by Shutterspeed

@ariusen whatever happened to the track spec diffuser.

http://www.zpost.com/forums/showthread.php?t=1339025

He actually got into a big project and had to delay without an estimate.
That?s why I?m going with this diffuser.

[inTgr8r]

Originally Posted by NavZ

This is probably a dumb q but with the angle of the diffuser so aggressive, doesn't it eliminate downforce? ie. lift the rear wheels?
As I understood it, the bottom plate is meant to smooth things out and the vertical fins are to provide stability (looking for input from aero gurus)

The angle is to expand and slow the fast moving air under the car so that it blends more smoothly with the slower air that comes over the top of the car to reduce turbulence behind.
To create downforce under the car you really need to extract air before it gets to the back. This can be done with NACA ducts and tubing to extract upstream.
Or, minimizing the air that gets under the car in the first place with splitters and reducing the gap under the front bumper.

The FW angle looks aggressive, but it basically follows the same line as the OE under tray.
A diffuser angle is considered too big when it causes the air to separate from the plane of diffuser.
It has to follow the plane to work effectively.

Since this one closely follows the stock piece I don't think it should be a problem.
Ideally a curved plane works best and that is the one shortcoming of the FW, but that does not mean it doesn't work well.
A diffuser is not really as much about down force as it is about minimizing turbulence behind the car and thus less drag.

Yes, the vertical fins are to reduce side wash which disturbs the underflow.
One of the excellent features of this diffuser is the large fin that catches the wash from the rear tires and directs it back.

BTW, I have already purchased one of these, otherwise I would be in on this GB.

[Frank851]

Originally Posted by inTgr8r

The angle is to expand and slow the fast moving air under the car so that it blends more smoothly with the slower air that comes over the top of the car to reduce turbulence behind.
To create downforce under the car you really need to extract air before it gets to the back. This can be done with NACA ducts and tubing to extract upstream.
Or, minimizing the air that gets under the car in the first place with splitters and reducing the gap under the front bumper.

The FW angle looks aggressive, but it basically follows the same line as the OE under tray.
A diffuser angle is considered too big when it causes the air to separate from the plane of diffuser.
It has to follow the plane to work effectively.

Since this one closely follows the stock piece I don't think it should be a problem.
Ideally a curved plane works best and that is the one shortcoming of the FW, but that does not mean it doesn't work well.
A diffuser is not really as much about down force as it is about minimizing turbulence behind the car and thus less drag.

Yes, the vertical fins are to reduce side wash which disturbs the underflow.
One of the excellent features of this diffuser is the large fin that catches the wash from the rear tires and directs it back.

BTW, I have already purchased one of these, otherwise I would be in on this GB.

Did you have to cut / remove any of the rear bumper to install, or is just a bolt on? Thanks.

[inTgr8r]

Originally Posted by Frank851

Did you have to cut / remove any of the rear bumper to install, or is just a bolt on? Thanks.

I haven't received it yet, but from what I understand its a straight bolt on.
But it depends on which mufflers are on the car.
There is a thread posted by the Hack where he had a fair amount to trim with the OE mufflers.
I have Stromung mufflers and expect a little trimming but not much.

There is no cutting of the bumper.

[angelr]

When would delivery start on these?

[AriuSen]

Originally Posted by NavZ

This is probably a dumb q but with the angle of the diffuser so aggressive, doesn't it eliminate downforce? ie. lift the rear wheels?
As I understood it, the bottom plate is meant to smooth things out and the vertical fins are to provide stability (looking for input from aero gurus)

Originally Posted by Beedub

is this functional?

you might like this video.....hes an aircraft engineer.....i really like his videos

[AriuSen]

Originally Posted by Slickback_Ben

Also from California! If I recall correctly, I locally picked up a sway bar from you a while back?

ohh yea...it was you...i remember now....good to see u lol

[3GFX]

I'd be interested to see price. If its a reasonable discount I'm in.

[inTgr8r]

Originally Posted by 3GFX

I'd be interested to see price. If its a reasonable discount I'm in.

Are you sure it would work with the 3.0(si) bumper and single exhaust?
It bolts up to the dual exhaust cutouts for the M bumper.

[Shutterspeed]

Originally Posted by AriuSen

He actually got into a big project and had to delay without an estimate.
That?s why I?m going with this diffuser.

Perhaps check out Driveway Labs or Velox Motorsports. They both make rear diffusers for the FRS/BRZ platform. I figure the Z is pretty close to the same size. And might be able to set something up for Z specific one.

[rockstar93]

ah...you can count me in as a definite participant. I'm in Ontario, Canada but if there's significant savings can take delivery in NY state.

[NYmpower]

How many people we got here so far,let's get it going I need this diffuser?

[3GFX]

Originally Posted by inTgr8r

Are you sure it would work with the 3.0(si) bumper and single exhaust?
It bolts up to the dual exhaust cutouts for the M bumper.

This would be a project

[inTgr8r]

Originally Posted by 3GFX

This would be a project

...ahhhhh
I see a dual exhaust mod in your future.

[3GFX]

Originally Posted by inTgr8r

...ahhhhh
I see a dual exhaust mod in your future.

No way, more weight that way mind you the diffuser might be the same

[Frank851]

Originally Posted by inTgr8r

I haven't received it yet, but from what I understand its a straight bolt on.
But it depends on which mufflers are on the car.
There is a thread posted by the Hack where he had a fair amount to trim with the OE mufflers.
I have Stromung mufflers and expect a little trimming but not much.

There is no cutting of the bumper.

I have the Stromung mufflers on my car as well. Let me know how your install goes once you get into it. Thanks.