Race Prep Miata race-only chat.
Sponsored by:
Sponsored by:

rear diffusers

Thread Tools
 
Search this Thread
 
Old 09-03-2010, 01:49 PM
  #21  
Senior Member
iTrader: (1)
 
spoolin2bars's Avatar
 
Join Date: May 2008
Location: south texas
Posts: 1,415
Total Cats: 10
Default

Originally Posted by thagr81 us
This is pretty much the truth... Just adding a rear diffuser won't really gain you anything except weight off the ***-end of the car without a fully functional aero package. But you will be JDM as fvck though...
why don't you try one and see for yourself. everyone that doesn't have one says that. keyword: R&D
but it does take some work and testing, if your not a motivated swimmer, you'll never see positive results.
spoolin2bars is offline  
Old 09-03-2010, 01:59 PM
  #22  
Elite Member
iTrader: (7)
 
jeff_man's Avatar
 
Join Date: May 2007
Location: Dallas, Tx
Posts: 3,006
Total Cats: 103
Default

jeff_man is offline  
Old 09-03-2010, 02:02 PM
  #23  
Elite Member
iTrader: (5)
 
thagr81 us's Avatar
 
Join Date: Apr 2007
Location: Wellford, SC
Posts: 1,697
Total Cats: 1
Default

Originally Posted by spoolin2bars
why don't you try one and see for yourself. everyone that doesn't have one says that. keyword: R&D
but it does take some work and testing, if your not a motivated swimmer, you'll never see positive results.
I'm not saying that you won't see ANY improvements... But if you have a fully sorted aero package the effects of the diffuser will be significantly increased.
thagr81 us is offline  
Old 09-03-2010, 02:13 PM
  #24  
Senior Member
iTrader: (1)
 
spoolin2bars's Avatar
 
Join Date: May 2008
Location: south texas
Posts: 1,415
Total Cats: 10
Default

Originally Posted by thagr81 us
I'm not saying that you won't see ANY improvements... But if you have a fully sorted (anything) the effects of the (whatever) will be significantly increased.
yes, that statement would be true regardless of what we were talkin' about.
spoolin2bars is offline  
Old 09-03-2010, 03:27 PM
  #25  
Newb
 
road-raser's Avatar
 
Join Date: Aug 2010
Location: harrisville, ms
Posts: 27
Total Cats: 0
Default

anyone know anything about the time this will be able?? i already have my bumper put out for this. i have a few road signs at the house and have been really thinking about fabbing up something just like this. im just not really sure about the angle and all that other stuff. thats kinda why i would rather buy one. then replicate it.
road-raser is offline  
Old 09-03-2010, 03:56 PM
  #26  
Elite Member
iTrader: (5)
 
thagr81 us's Avatar
 
Join Date: Apr 2007
Location: Wellford, SC
Posts: 1,697
Total Cats: 1
Default

Speaking of road signs... Wasn't there someone who made one of out road signs before? I know FM did a photo of a sign being used under the car a long time back, but I thought there was a diffuser one too.
thagr81 us is offline  
Old 09-03-2010, 04:04 PM
  #27  
Senior Member
iTrader: (1)
 
spoolin2bars's Avatar
 
Join Date: May 2008
Location: south texas
Posts: 1,415
Total Cats: 10
Default

road signs? aren't those steel? sounds waaayyy too heavy to me. i'd use aluminum.
spoolin2bars is offline  
Old 09-03-2010, 04:05 PM
  #28  
Elite Member
iTrader: (5)
 
thagr81 us's Avatar
 
Join Date: Apr 2007
Location: Wellford, SC
Posts: 1,697
Total Cats: 1
Default

Not saying that I would make mine out of them, but if you are on a budget and want to be creative it WOULD work.
thagr81 us is offline  
Old 09-03-2010, 05:09 PM
  #29  
Newb
 
road-raser's Avatar
 
Join Date: Aug 2010
Location: harrisville, ms
Posts: 27
Total Cats: 0
Default

well my road signs are deff aluminum. i have a huge one that i got from the old wilson dodge place that i was going to cut and make a flat bottom tray out of for my car. i had a splitter on my ae86 that was made out of a hyw 49 sign. i use what i can get my hands on. i didn't steal any of them i wait till i see them putting up new signs and pay off the road crew for the big ones.
road-raser is offline  
Old 09-03-2010, 08:00 PM
  #30  
Senior Member
iTrader: (5)
 
Gotpsi?'s Avatar
 
Join Date: Jan 2008
Location: Central, TX / Bay area, CA
Posts: 1,260
Total Cats: 5
Default

Yes road signs are defiantly aluminum. I have stacks of them at work that are not useful anymore that I plan on using for my aero project.
Gotpsi? is offline  
Old 09-03-2010, 08:40 PM
  #31  
Elite Member
iTrader: (5)
 
thagr81 us's Avatar
 
Join Date: Apr 2007
Location: Wellford, SC
Posts: 1,697
Total Cats: 1
Default

Wirelessly posted

I would be interested in said projects... Haven't decided what I want to use as my flat bottom yet and additional ideas are always great.
thagr81 us is offline  
Old 09-03-2010, 08:46 PM
  #32  
Junior Member
iTrader: (3)
 
Reverend Greg's Avatar
 
Join Date: Apr 2009
Location: McDonough Ga.
Posts: 350
Total Cats: -26
Default

I have some .040" thick 7475 Aluminum Im using for this stuff,under shrouds and the like.I got it cheap,you really cant weld it well and I doesnt like to be bent either.But it is light and stiff.I have no Idea what it would cost to buy on the open market..Edit:$147.50 for a 4'x8' sheet from aircraft spruce
(G)

Last edited by Reverend Greg; 09-03-2010 at 08:52 PM. Reason: Add prices
Reverend Greg is offline  
Old 09-03-2010, 09:04 PM
  #33  
Newb
 
road-raser's Avatar
 
Join Date: Aug 2010
Location: harrisville, ms
Posts: 27
Total Cats: 0
Default

,you really cant weld it well and I doesnt like to be bent either
yea its not very pure. it has other metals mixed in with it to keep is more rigid i think. thats kinda why i been putting off not welding up this stuff i have here. there is a sign store not far from my house. i need to go talk to them about where to get some good good clean aluminum.
road-raser is offline  
Old 09-03-2010, 09:11 PM
  #34  
Junior Member
 
94blackmx5's Avatar
 
Join Date: Mar 2009
Location: maine
Posts: 221
Total Cats: -1
Default

Originally Posted by jeff_man
This is about as good as it gets. The drag from the OEM bumper is almost if not totaly eliminated.
94blackmx5 is offline  
Old 09-03-2010, 09:56 PM
  #35  
Elite Member
iTrader: (5)
 
thagr81 us's Avatar
 
Join Date: Apr 2007
Location: Wellford, SC
Posts: 1,697
Total Cats: 1
Default

Wirelessly posted

Matt does have an aerodynamicist working with him on the aero develop of the car. They have definitely made leaps and bounds in the Miata world for sure...
thagr81 us is offline  
Old 09-04-2010, 01:28 AM
  #36  
Senior Member
 
firedog25's Avatar
 
Join Date: May 2006
Posts: 917
Total Cats: -8
Default

I'm not a mechanical engineer or anything but all the different oem diffusers that I've seen on performance variants aren't obnoxiously huge like some of those pictured here.
firedog25 is offline  
Old 09-04-2010, 02:23 AM
  #37  
Elite Member
iTrader: (1)
 
Full_Tilt_Boogie's Avatar
 
Join Date: May 2009
Location: Jacksonville, FL
Posts: 5,155
Total Cats: 406
Default

Originally Posted by firedog25
I'm not a mechanical engineer or anything but all the different oem diffusers that I've seen on performance variants aren't obnoxiously huge like some of those pictured here.
Thats because most of them dont do anything
Full_Tilt_Boogie is offline  
Old 09-04-2010, 11:09 AM
  #38  
Asx
Junior Member
iTrader: (1)
 
Asx's Avatar
 
Join Date: Nov 2007
Location: Huntsville, AL
Posts: 78
Total Cats: 3
Default

Not extremely relevant to this discussion, but if your diffuser is made of aluminum you can dump your exhaust in at a nice angle and it willspeed up the flow. I can scan some pages of the Milliken book that cover diffuser design when I get back from the track
Asx is offline  
Old 09-04-2010, 11:29 AM
  #39  
Elite Member
iTrader: (5)
 
thagr81 us's Avatar
 
Join Date: Apr 2007
Location: Wellford, SC
Posts: 1,697
Total Cats: 1
Default

Wirelessly posted

I would like to see how this theory works and how subtle the blend in would need to be to prevent turbulence from being formed. Post those scans when you get the opportunity.
thagr81 us is offline  
Old 09-04-2010, 01:30 PM
  #40  
Newb
 
road-raser's Avatar
 
Join Date: Aug 2010
Location: harrisville, ms
Posts: 27
Total Cats: 0
Default

Originally Posted by Asx
Not extremely relevant to this discussion, but if your diffuser is made of aluminum you can dump your exhaust in at a nice angle and it willspeed up the flow.
very true but wouldn't that mean when you lift off the throttle it would interupt the "flow"?? or the more exhaust there is the more thats being forced out the diffuser and at some point it would creat some unwanted turbulence. might not be the best idea for the high hp, high exhaust flowing turbo guys. if im wrong let me know. these are just my
road-raser is offline  


Quick Reply: rear diffusers



All times are GMT -4. The time now is 11:53 AM.