R3VLimited Forums

Go Back   R3VLimited Forums > General Forums > Track & AutoX

Reply
 
Thread Tools
Old 01-24-2014, 09:21 PM   #16
BlackbirdM3
R3VLimited
 
BlackbirdM3's Avatar
 
Join Date: Jan 2012
Location: Napa ca
Posts: 2,263
Quote:
Originally Posted by E30_Pare View Post
i thought a gurney flap was just to improve stability at speed.
Think about that... Downforce weights the rear of the car improving stability. The front splitter does a similar thing, but up front. If you increase one, you need to increase the other to balance the car.

I admit to this, I've done 140 mph in my M3 (a very long straight road, that wasn't smooth) and I have to say the car was rock solid despite the road being pretty rough.

Will
__________________
'59 Alfa Romeo 101.02 Giulietta Sprint
'69 Alfa Romeo 105.51 1750 GTV (R.I.P)
'69 Datsun 2000 roadster Vintage race car
'88 BMW M3
BlackbirdM3 is offline   Reply With Quote
Old 01-24-2014, 10:55 PM   #17
jalopi
Banned
 
Join Date: Aug 2010
Location: Towson
Posts: 2,372
I think 1980s BMW didn't go too crazy with the aero on the m3's cuz they knew the cokebinge everyone was on would only go too far with purchases... normal people don't go for cars with massive wings and shit... that was a niche market reserved for lamborghini
jalopi is offline   Reply With Quote
Old 01-25-2014, 12:30 AM   #18
kamotors
R3V OG
 
kamotors's Avatar
 
Join Date: Nov 2007
Location: reno
Posts: 7,035
__________________

ORDER PARTS-
kamotorsperformance.com
neuemotorsports.com

Info Here-[/B]KAMOTORS Performance-parts on Facebook
PM me for BOLT ON M20 turbo kits and Tuning.
kamotors is offline   Reply With Quote
Old 01-25-2014, 12:55 AM   #19
rwh11385
lance_entities
 
rwh11385's Avatar
 
Join Date: Oct 2003
Location: internetz
Posts: 18,300
Quote:
Originally Posted by RoccoB517 View Post
rwh11385, what wing is that on the red car? I like the mounting. The uprights look very well done.
I think Brooks Motorsports Composites: http://brooksmotorsport.com/products/

His mentions:
http://forums.bimmerforums.com/forum...0#post25714380
http://forums.bimmerforums.com/forum...8#post25795058
http://forums.bimmerforums.com/forum...ort-Composites


Quote:
Originally Posted by NigelStu View Post
This cheap stupid stuff was worth 1-1.5 seconds per lap at Gingerman (South Haven Michigan).

splitter is just 3/8 plywood. Wing has a proper airfoil shape (wood ribs with foam core)

Yesssss.
__________________
rwh11385 is offline   Reply With Quote
Old 01-25-2014, 07:44 AM   #20
Eric
R3V Elite
 
Join Date: Feb 2004
Location: Colorado Springs
Posts: 5,073
Send a message via AIM to Eric

DSCN4019 by ericandshovin, on Flickr

Found another one

Last edited by Eric; 01-25-2014 at 09:11 AM.
Eric is offline   Reply With Quote
Old 01-25-2014, 08:09 AM   #21
Ether-D
R3VLimited
 
Ether-D's Avatar
 
Join Date: Sep 2011
Location: Franklin, TN
Posts: 2,828
Quote:
Originally Posted by rwh11385 View Post




There's some running them. And IIRC, don't have to spend too much (i.e. ebay) as long as they are structurally sound.
I built that splitter on the yellow car (Treehouse Racing). Worked on Akard's car too. About 9 years ago… Time flies.
__________________
Quote:
Originally Posted by Andy.B
Whenever I am about to make a particularly questionable decision regarding a worryingly cheap diy solution, I just ask myself, "What would Ether-D do?"
1987 325iS m30b34 Muscle car (Engine electrical phase)
~~~~~~~~~~
I was born on 3/25…
~~~~~~~~~~
Ether-D is offline   Reply With Quote
Old 01-25-2014, 12:50 PM   #22
Northern
R3VLimited
 
Northern's Avatar
 
Join Date: Nov 2010
Location: Halifax, N.S.
Posts: 2,684
Send a message via ICQ to Northern Send a message via AIM to Northern Send a message via MSN to Northern Send a message via Yahoo to Northern
Quote:
Originally Posted by BlackbirdM3 View Post
Best aero mods for an E30? Pretty simple, look at an M3, all done by the factory,tested, and race approved. The rear window and trunk lid made a huge difference in reducing drag. That alone lowered the CoD from 0.39 to 0.33, front splitter and airdam? Evo 2 airdam with Evo3 splitter. Seal up all the gaps around the hood and grill, (all stock evo parts that can be ordered with little trouble.)

Will
It might be worth some time looking into if you could find a way to mimic that, as well as the m3's under panels around the spare tire well (or cut it out for a diffuser)

I think the gurney flap spoilers would be less effective than an actual wing if we're taking drag into account. I obviously don't have any numbers, but the gurney flap does not seem very aerodynamic, plus it is in the wake of the car and not very wide. A full blown wing will be up higher, wider, with more surface area, and much less drag. On the downside, it will be heavier. Not just the weight of the wing, but the mounts you will need to hold it in place.
__________________
E30VON_NS 
Quote:
Originally Posted by priapism View Post
My girl don't know shit, but she bakes a mean cupcake.
Quote:
Originally Posted by shameson View Post
Usually it's best not to know how much money you have into your e30
Northern is offline   Reply With Quote
Old 01-25-2014, 01:28 PM   #23
rwh11385
lance_entities
 
rwh11385's Avatar
 
Join Date: Oct 2003
Location: internetz
Posts: 18,300
Quote:
Originally Posted by Ether-D View Post
I built that splitter on the yellow car (Treehouse Racing). Worked on Akard's car too. About 9 years ago… Time flies.
Sweet. I met Jon about that era with the ugly but awesome yellow/green racecar. Bluegrass race weekend 2005, and the sticker was the best part:



I forgot who ran an off the shelf / ebay ricer wing but thought it was someone in e30 world.

Quote:
Originally Posted by Northern View Post
It might be worth some time looking into if you could find a way to mimic that
http://www.airtab.com/how.html

E30 are brick-like so could benefit with a few of these near the rear of the roof to reduce drag. Someone should run CFD on this topic. Anyone have an E30 made in CAD already?
__________________

Last edited by rwh11385; 01-25-2014 at 01:42 PM.
rwh11385 is offline   Reply With Quote
Old 01-25-2014, 04:11 PM   #24
BlackbirdM3
R3VLimited
 
BlackbirdM3's Avatar
 
Join Date: Jan 2012
Location: Napa ca
Posts: 2,263
Vortex generators, yes those might be helpful. The bump above the rear window on the M3 serves much the same purpose causing the boundary layer to trip and spill onto the spoiler. I've sort of wondered what would happen if one were to add some to the existing setup on the M3.

I have to admit it would be fun to stick an E30 in both normal and M3 form in a windtunnel and see what the airflow differences are. Then add things like the EVO front splitter and a set of extra vortex generators and that sort of thing to see just what does actually make a difference and what doesn't.

Will
__________________
'59 Alfa Romeo 101.02 Giulietta Sprint
'69 Alfa Romeo 105.51 1750 GTV (R.I.P)
'69 Datsun 2000 roadster Vintage race car
'88 BMW M3
BlackbirdM3 is offline   Reply With Quote
Old 01-25-2014, 04:57 PM   #25
Jaxx_
E30 Mastermind
 
Jaxx_'s Avatar
 
Join Date: Dec 2009
Location: Bay Area, CA, USA
Posts: 1,623
Thought you might enjoy looking at these autospeed articles:

http://www.autospeed.com/A_111110/hD...s/article.html
http://www.autospeed.com/cms/A_111111/article.html
http://www.autospeed.com/cms/article.html?&A=108656
http://www.autospeed.com/cms/A_2455/article.html
http://www.autospeed.com/cms/A_2456/article.html
http://www.autospeed.com/cms/A_112609/article.html


larger here: https://fbcdn-sphotos-g-a.akamaihd.n...57241711_o.jpg

It was good enough to make a noticeable difference at the top of 2nd gear (max speed for autox territory), but in order to make a real difference you need some fresh air (above the roof line). This was in accordance to the Street Prepared rules(10" spoiler in any direction)

edit: also, minimizing turbulence does not necessarily mean that you are creating downforce. Some of you guys are on the right track with creating laminar flow and removing turbulence. getting rid of(or minimizing) low pressure zones on top of the car will be worth your time. VGs have their limit of effectiveness, and they reach a point of diminishing returns. I think that's outlined in one of the articles I link.
__________________
'00 323i M52TUB25 | sedan with a backpack | 354 - Titanium Silver | MS42
'84 318i M10B18 | 93whp/90ftlbs | 147- Safari Beige | MS2E w/ LC, 2-Step

Last edited by Jaxx_; 01-25-2014 at 05:05 PM.
Jaxx_ is offline   Reply With Quote
Old 01-25-2014, 05:50 PM   #26
rwh11385
lance_entities
 
rwh11385's Avatar
 
Join Date: Oct 2003
Location: internetz
Posts: 18,300
http://forums.bimmerforums.com/forum...tex-generators




Since it might not be practical or feasible to change out the rear window and C pillars, a few bucks for VGs might help. Ebay big wing and whatever splitter-like things you can stick on the front.

Im gonna have to have fun and experiment when I get a LeMons of my own.
__________________
rwh11385 is offline   Reply With Quote
Old 01-25-2014, 06:22 PM   #27
Ether-D
R3VLimited
 
Ether-D's Avatar
 
Join Date: Sep 2011
Location: Franklin, TN
Posts: 2,828
@RWH, I was there that weekend. It was hotter than the devils anus and I was changing tires the whole time I think...
__________________
Quote:
Originally Posted by Andy.B
Whenever I am about to make a particularly questionable decision regarding a worryingly cheap diy solution, I just ask myself, "What would Ether-D do?"
1987 325iS m30b34 Muscle car (Engine electrical phase)
~~~~~~~~~~
I was born on 3/25…
~~~~~~~~~~
Ether-D is offline   Reply With Quote
Old 01-25-2014, 11:41 PM   #28
TobyB
No R3VLimiter
 
TobyB's Avatar
 
Join Date: Oct 2011
Location: Carnation WA usa
Posts: 3,158
The stock E30 is drag limited at an absurdly low speed, so keeping drag down may actually
be more beneficial than trying to add download for corners- any gain in the corners can
be more than eaten up in a straight line by drag.
That said, aero download that doesn't cost you much in drag,
especially something like a big front splitter,
will let you readjust suspension settings (in particular, reducing static front camber)
to gain in other areas, particularly braking.

Racing isn't always the best guide, though, as the M3 in DTM was aero- restricted-
sure, they did the best the factory could, but they were restrained by rules that may
not apply to you. Likewise, there is "no" aero development in Pro3 because we can't.
Not because we don't want to.

And Mythbusters proved that you want to dimple it just like the golf ball, didn't they?

t

(ps, a Gurney flap is a way to increase wing download a LOT at the cost of relatively
minimum drag, and since it's easy to change, it's very useful for tuning)
__________________
Quote:
now, sometimes I just mess with people. It's more entertaining that way. george graves
TobyB is offline   Reply With Quote
Old 01-26-2014, 12:58 AM   #29
RoccoB517
Wrencher
 
Join Date: Jul 2013
Location: Glendale, AZ
Posts: 248
A pretty good explanation of gurney flaps.

http://www.youtube.com/watch?v=TK8-VuwPqq4
RoccoB517 is offline   Reply With Quote
Old 01-26-2014, 02:26 AM   #30
SA E30
E30 Fanatic
 
Join Date: Feb 2004
Location: Johannesburg, South Africa
Posts: 1,248
Send a message via MSN to SA E30
__________________
SA E30 is offline   Reply With Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not 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 -7. The time now is 12:57 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Copyright 2004 - 2020 R3VLimited LLC