Rear diffuser? - Page 5 - Ford Focus Forum, Ford Focus ST Forum
Ford Focus Forum
HomeContact UsAbout UsGalleryDiscussion ForumsMarketplace


Go Back   Ford Focus Forum, Ford Focus ST Forum > Ford Focus Third Generation > MK3 Focus

MK3 Focus The place to chat about general questions, window tinting, exterior body, interior and lighting upgrades for the third generation 2012-Current Focus.

Search This Forum | Image Search | Advanced Search    
Ford Focus Tire & Wheels FocusFanatics Merchandise

Reply
 
Thread Tools Display Modes
Old 04-15-2012, 04:28 PM   #41
bsp_53
Focus Addict
 
bsp_53's Avatar
 
Join Date: Jul 2011
Fan#: 87580
Location: Millinocket, ME
What I Drive: 2012 FF Titanium HB, Yellow Blaze

Posts: 683
Points 519, Level 10
Points: 519, Level: 10 Points: 519, Level: 10 Points: 519, Level: 10
Level Up 38% Completed
Level up: 38% Level up: 38% Level up: 38%
Forum Activity 0%
Activity: 0% Activity: 0% Activity: 0%
FF Reputation: 1 bsp_53 Good Standing Member
Buy-Sell-Trade Rating: (0)
Quote:
Originally Posted by stang74shelby View Post
Sweet, can't wait
^^ This!
__________________
Gold Nugget: '12, 400A, Wintr Pckg, Yellow Blaze HB
Mods: Llumar Tint:35 / 20; K&N fltr + Snrkl Del.; Splashgrds; Grill Pinstripes
Hatch Nation #174
bsp_53 is offline  
    Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 04-15-2012, 10:55 PM   #42
andcool69
Focus Enthusiast
 
andcool69's Avatar
 
Join Date: Oct 2011
Fan#: 90504
Location: 18372, PA
What I Drive: 2012 Race Red Focus

Posts: 313
FF Reputation: 1 andcool69 Good Standing Member
Buy-Sell-Trade Rating: (0)
Let's see how it came out!!
__________________
2012 Ford Focus HB Race Red 5 spd
Born Oct.4 Delivered Oct. 22
BUILD THREAD
http://andcool69.blogspot.com/?view=sidebar
andcool69 is offline  
    Reply With Quote Quick reply to this message
Old 04-16-2012, 04:55 AM   #43
Sonic_HedgeHog
Sonic Mk3 Crew #00
 
Sonic_HedgeHog's Avatar
 
Join Date: Sep 2007
Fan#: 50003
Location: Albuquerque, NM
What I Drive: '12 Sterling Focus SE 5dr Sport Pkg

Posts: 13,495
Points 123,836, Level 100
Points: 123,836, Level: 100 Points: 123,836, Level: 100 Points: 123,836, Level: 100
Level Up 0% Completed
Level up: 0% Level up: 0% Level up: 0%
Forum Activity 2%
Activity: 2% Activity: 2% Activity: 2%
FF Reputation: 19 Sonic_HedgeHog Great Standing Member
Buy-Sell-Trade Rating: (1)
I'm curious if you were able to mock something up too...
__________________
Hatch Nation #156. Sonic's Mk3 Crew Founder and #00
Moderator: DURATEC Ti-VCT Performance, ST Performance, MK3 Focus, SW Fanatics, Sonic's MK3 Crew
Sonic_HedgeHog is offline  
    Reply With Quote Quick reply to this message
Old 04-16-2012, 02:28 PM   #44
Chaos09
Sonic Crew #09
 
Chaos09's Avatar
 
Join Date: Feb 2012
Fan#: 95090
Location: Alexandria, VA
What I Drive: Slammed S-10

Posts: 3,544
Points 7,879, Level 59
Points: 7,879, Level: 59 Points: 7,879, Level: 59 Points: 7,879, Level: 59
Level Up 65% Completed
Level up: 65% Level up: 65% Level up: 65%
Forum Activity 1%
Activity: 1% Activity: 1% Activity: 1%
FF Reputation: 7 Chaos09 Good Standing Member
Buy-Sell-Trade Rating: (5)
I know everyone has been waiting, so here it is. Just let me know what you think. We went without the winglets on this design. I might put them on just to see. If people order they need to let us know if they has stock exhaust or aftermarket. This one is for stock and we will supply the exhaust hole. If you have aftermarket then you will have to cut your own.
I got over 1 MPG average driving 60mph-75mph. I also got an improvement from in town driving.













__________________
Sonic's MK3 Crew #9 Chaos!
Chaos09 is offline  
    Reply With Quote Quick reply to this message
Old 04-16-2012, 02:29 PM   #45
Chaos09
Sonic Crew #09
 
Chaos09's Avatar
 
Join Date: Feb 2012
Fan#: 95090
Location: Alexandria, VA
What I Drive: Slammed S-10

Posts: 3,544
Points 7,879, Level 59
Points: 7,879, Level: 59 Points: 7,879, Level: 59 Points: 7,879, Level: 59
Level Up 65% Completed
Level up: 65% Level up: 65% Level up: 65%
Forum Activity 1%
Activity: 1% Activity: 1% Activity: 1%
FF Reputation: 7 Chaos09 Good Standing Member
Buy-Sell-Trade Rating: (5)
We are also working on the front. There is a piece of carpet that we are going to make aluminum for better airflow. Will also post the gains from it as well.
__________________
Sonic's MK3 Crew #9 Chaos!
Chaos09 is offline  
    Reply With Quote Quick reply to this message
Old 04-16-2012, 02:42 PM   #46
darkangelism
Sonic Crew #04
 
darkangelism's Avatar
 
Join Date: May 2011
Fan#: 85425
Location: oklahoma city, OK
What I Drive: 2012 Focus Titanium Hatch

Posts: 7,367
Points 4,304, Level 41
Points: 4,304, Level: 41 Points: 4,304, Level: 41 Points: 4,304, Level: 41
Level Up 77% Completed
Level up: 77% Level up: 77% Level up: 77%
Forum Activity 1%
Activity: 1% Activity: 1% Activity: 1%
FF Reputation: 9 darkangelism Good Standing Member
Buy-Sell-Trade Rating: (0)
How much are you going to charge? I will probably get one after I get my fswerks exhaust installed. Which will be after I finish building my heat shield for the steeda, so maybe another month or 2. I would probably vinyl it black to match my paint.
darkangelism is online now  
    Reply With Quote Quick reply to this message
Old 04-16-2012, 02:51 PM   #47
chaimav
Focus Enthusiast
 
Join Date: Nov 2011
Fan#: 91850
Location: Pikesville, MD
What I Drive: Sterling Gray 2012 SEL Hatch

Posts: 298
FF Reputation: 2 chaimav Good Standing Member
Buy-Sell-Trade Rating: (0)
Ok, so here is a stupid question: If this piece of sheet metal can gain 1 MPG, why didn't Ford include it?

I'm not trying to be smart here, but I assume there has got to be some trade-off somehwere...
Is it just cost? Does it cause a build up of heat? Is it more likely to snag something on the road?
chaimav is offline  
    Reply With Quote Quick reply to this message
Old 04-16-2012, 02:56 PM   #48
Chaos09
Sonic Crew #09
 
Chaos09's Avatar
 
Join Date: Feb 2012
Fan#: 95090
Location: Alexandria, VA
What I Drive: Slammed S-10

Posts: 3,544
Points 7,879, Level 59
Points: 7,879, Level: 59 Points: 7,879, Level: 59 Points: 7,879, Level: 59
Level Up 65% Completed
Level up: 65% Level up: 65% Level up: 65%
Forum Activity 1%
Activity: 1% Activity: 1% Activity: 1%
FF Reputation: 7 Chaos09 Good Standing Member
Buy-Sell-Trade Rating: (5)
Here's how it works. 1 As the air goes under the car it gets caught by the rear bumper. 2 The air under the car moves slower than on top. By using the sheet aluminum it keeps the air from getting caught up under the car and speeds the air back up.
__________________
Sonic's MK3 Crew #9 Chaos!
Chaos09 is offline  
    Reply With Quote Quick reply to this message
Old 04-16-2012, 02:56 PM   #49
ralck
Focus Enthusiast
 
Join Date: Mar 2012
Fan#: 96372
Location: Rochester, NY
What I Drive: My sister's car while it is salty

Posts: 222
FF Reputation: 1 ralck Good Standing Member
Buy-Sell-Trade Rating: (1)
Quote:
Originally Posted by chaimav View Post
Ok, so here is a stupid question: If this piece of sheet metal can gain 1 MPG, why didn't Ford include it?

I'm not trying to be smart here, but I assume there has got to be some trade-off somehwere...
Is it just cost? Does it cause a build up of heat? Is it more likely to snag something on the road?
My best guess, which should be taken with a huge grain of salt as I have little experience/expertise in all of this, would be cost.

I'm basing this off the Mazda CX-5 Mazda just released. The entire underside of that car has diffuser panels on it to reduce drag and increase MPGs. It is class leading fuel economy and beats out a bunch of mid sized cars too! But they can do that because they charge a pretty penny for that car.
ralck is offline  
    Reply With Quote Quick reply to this message
Old 04-16-2012, 02:59 PM   #50
Chaos09
Sonic Crew #09
 
Chaos09's Avatar
 
Join Date: Feb 2012
Fan#: 95090
Location: Alexandria, VA
What I Drive: Slammed S-10

Posts: 3,544
Points 7,879, Level 59
Points: 7,879, Level: 59 Points: 7,879, Level: 59 Points: 7,879, Level: 59
Level Up 65% Completed
Level up: 65% Level up: 65% Level up: 65%
Forum Activity 1%
Activity: 1% Activity: 1% Activity: 1%
FF Reputation: 7 Chaos09 Good Standing Member
Buy-Sell-Trade Rating: (5)
A diffuser, in an automotive context, is a shaped section of the car underbody which improves the car's aerodynamic properties by enhancing the transition between the high-velocity airflow underneath the car and the much slower freestream airflow of the ambient atmosphere. It works by providing a space for the underbody airflow to decelerate and expand so that the boundary between the car's airflow and "external" airflow is less turbulent. It also provides a degree of "wake infill" (the wake being a turbulent area of low pressure that is caused by the passage of the vehicle through the air; this can cause pressure drag).

As the air enters towards the front of the car it accelerates and reduces pressure. There is a second suction peak at the transition of the flat bottom and diffuser. The diffuser then eases this high velocity air back to normal velocity and also helps fill in the area behind the car making the whole underbody a more efficient downforce producing device by reducing drag on the car and increasing downforce.

The aft part of a car underbody can be a diffuser. It works to bring the low pressure air below the car back to the ambient atmospheric pressure without inducing turbulence. It uses Bernoulli's principle, such that the pressure increases while the velocity decreases. Since the pressure below the car is lower than on the side and above the car, downforce is produced if implemented correctly. Injecting the exhaust into the rear diffuser can also help extract the air from below the car. The exhaust gasses effectively energize the boundary layer, helping to raise the pressure of the low-pressure, fast-moving airstream back to the ambient atmospheric pressure at the exit of the diffuser. This helps extract the air more efficiently from the underbody.

Note that the front of the car slows down the air without a diffuser making this the ideal place for an inlet. Instead, a splitter is commonly used here. The splitter serves to reduce the pressure below the front of the car and thereby increase the amount of downforce in that region. The airstream is brought to stagnation above the splitter, by an air dam, causing an area of high pressure. Below the splitter, air is accelerated, as stated above, which causes the pressure to drop and create downforce. Some race cars, such as the Toyota GT-One actually use a proper diffuser in this area to help create more downforce
__________________
Sonic's MK3 Crew #9 Chaos!
Chaos09 is offline  
    Reply With Quote Quick reply to this message
Reply

Bookmarks & Social Networks

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Ford Focus Forum, Ford Focus ST Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 04:07 PM.


Copyright 2002-2014 FocusFanatics.com. All Rights Reserved : Privacy Policy : Advertise Information

Focus Fanatics Ford Focus Forum offers many fun ways for you to engage with other Ford Focus Owners from across the world. Whether it be about the aftermarket performance modifications, technical how-to's, European tuned suspension or awesome fuel economy similar to the Cadillac ATS-V, Ford Fusion and Acura TLX. You can find all Ford Focus and Focus ST related information here. Join our Ford Focus discussion forums and chat with local Focus enthusiasts in your area.