Go Back   EcoModder Forum > EcoModding > Aerodynamics
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 04-17-2014, 03:56 AM   #1 (permalink)
NightKnight
 
NachtRitter's Avatar
 
Join Date: Dec 2008
Location: Placerville, CA
Posts: 1,594

RippinRoo - '05 Subaru Legacy Wagon 2.5 GT
Subaru
90 day: 21.16 mpg (US)

Helga - '00 Volkswagen Jetta TDI
TEAM VW AUDI Group
Diesel
90 day: 53.91 mpg (US)

Olga - '03 Volkswagen Jetta Wagon
90 day: 46.24 mpg (US)
Thanks: 303
Thanked 308 Times in 184 Posts
VW MkIV Aerodynamic Mods (Jetta, Golf)

Thought I'd consolidate a few VW MkIV (Jetta: 1999.5 to 2005, and Golf: 1997 to 2004) aerodynamic threads since I have some interest in that subject

Actually, I could not find any good MkIV Golf threads, so I'd appreciate if others could provide links & pics. I think COcyclist has done some aero mods to his Golf, but was not able to find any related threads.

Since I'm a visual guy, I'm primarily interested in pics with descriptions of mods rather than text only.

While the aero mods are not engine-specific, the TDI seems to benefit greatly from them. The combination of some aero mods plus a taller top gear allows me to get in the 60's mpg for an entire tank (for example, ~64mpg with avg speed of ~60mph over ~975 miles a year ago; see my April 2013 entries).

An excellent starting point for aero mods on any car is the page 65+ Vehicle modifications for better fuel economy - EcoModder.com.

Onward, then, with the MkIV-specific mods, in no particular order.

** deejaaa **
User deejaaa has done some interesting stuff to his getto (Fuel Log):
- Grill block:

- Front under-panel (between bumper and skid plate):

- Rear boxing:


These are all in this thread: 02 TDI Jetta grille block

Deejaaa also posted some images which could be used to sketch out some aero ideas, found in this thread: http://ecomodder.com/forum/showthread.php/1999-2005-jetta-bora-variant-model-template-23590.html


I haven't seen any rear skirts done on a MkIV, but deejaaa is looking for ideas on how to mount a skirt in this thread: 02 Jetta, need rear skirt mount ideas....

** DIY GUY **
User DIY GUY, who is no longer active, has a Jetta TDI (Fuel Log) for which he did a pretty clean grill block:


This can be found in thread 02 Jetta Tdi Grille block w/ Ram Air?

** Deezler **
User Deezler, also no longer active, did some clean aero mods to his Bio Deezler (Fuel Log):
- Grill Block:

- Front under-body:

- Rear diffuser:

- Passenger mirror delete:


All from this thread: Deezler's 2003 Jetta TDI Build Thread

Deezler also tried out vortex generators:

See this thread for more details: Tuft Testing - "Vortekz" vortex generators on 2003 Jetta Rear Window

** Trebuchet03 **
User trebuchet03 did some pretty in-depth flow modeling on his Jetta (which he no longer has):


The thread here has some great discussion: Trebuchet03's JettKamm (2000 VW Jetta)

Trebuchet03 also performed some aero mods on his Jetta:
- Front tire air deflector:

- Smaller driver's mirror:


Details are in this thread: Tas's 2000 Jetta TDI Build Thread

** metroschultz **
User metroschultz did some very nice bumper side vent covers and wheel covers for his daughter's car:
- Side vent covers:

- Wheel covers:


Some details are available in this thread: Schultz's Jetta aero mods thread

** NachtRitter **
I've also done a few aero mods to Helga (Fuel Log):
- Grill block:

- Front under-body (combines with skid plate to cover nearly everything up to the firewall):

- Rear under-body (covers from axle back to the rear bumper):

- Currently working on figuring out how to mount these pizza pans to the aluminum wheels:


Unfortunately I don't yet have any build threads for my own projects.

That's all I've got for now. If you have any other MkIV aero mods, please feel free to add below!

  Reply With Quote
The Following 5 Users Say Thank You to NachtRitter For This Useful Post:
aerohead (04-19-2014), Cd (10-11-2014), ecomodded (06-24-2014), Lane_S (04-23-2014), Xist (10-10-2014)
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 04-17-2014, 03:08 PM   #2 (permalink)
Aero Wannabe
 
COcyclist's Avatar
 
Join Date: Dec 2007
Location: NW Colo
Posts: 545

TDi - '04 VW Golf
TEAM VW AUDI Group
90 day: 55.96 mpg (US)
Thanks: 354
Thanked 111 Times in 89 Posts
Thanks for starting this thread. The mk IV Golf/Jetta diesels respond well to aero mods especially the upper grill block. I have a full (bumper to bumper) belly pan but haven't started a thread because I am a Luddite when it comes to posting photos. I do have some in my albums if anyone would like to move some to this thread.

Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - COcyclist's Album: Belly Pan Install

Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - COcyclist's Album: TDi photos

FWIW I only use the coroplast nose in winter to protect my grill. I stuffed pipe insulation between the grill bars on the upper grill and leave that in place all year round.
__________________
60 mpg hwy highest, 55+mpg lifetime
TDi=fast frugal fun
make NOx not Carbon


"I worked on the wiring to see if I could get the alternator to charge. The stud was loose and I accidentally let the white smoke out of the box... Alternators, among other things, run on white smoke. Once you let the white smoke out they no longer work!" planejob
  Reply With Quote
The Following User Says Thank You to COcyclist For This Useful Post:
aerohead (04-19-2014)
Old 04-17-2014, 11:13 PM   #3 (permalink)
NightKnight
 
NachtRitter's Avatar
 
Join Date: Dec 2008
Location: Placerville, CA
Posts: 1,594

RippinRoo - '05 Subaru Legacy Wagon 2.5 GT
Subaru
90 day: 21.16 mpg (US)

Helga - '00 Volkswagen Jetta TDI
TEAM VW AUDI Group
Diesel
90 day: 53.91 mpg (US)

Olga - '03 Volkswagen Jetta Wagon
90 day: 46.24 mpg (US)
Thanks: 303
Thanked 308 Times in 184 Posts
Thanks COcyclist! Hadn't thought to look into your ecomodder album...

Here are the details of COcyclist's belly pan on his Golf:

- Using the rubber inserts under the body as mount points (no drilling into the part of the car that you don't want to rust!):

- And some pics of the results:


- Nice shields on the rear wheel wells



His grill block looks like this:



There are a few more pics of the belly pan and the grill block; see COcyclists link above.
  Reply With Quote
The Following 3 Users Say Thank You to NachtRitter For This Useful Post:
aerohead (04-19-2014), Cd (10-11-2014), COcyclist (04-18-2014)
Old 04-18-2014, 10:24 AM   #4 (permalink)
Aero Wannabe
 
COcyclist's Avatar
 
Join Date: Dec 2007
Location: NW Colo
Posts: 545

TDi - '04 VW Golf
TEAM VW AUDI Group
90 day: 55.96 mpg (US)
Thanks: 354
Thanked 111 Times in 89 Posts
In the second photo, I have since covered the cat/con from the skid plate to the coroplast with aluminum flashing with no heat problems over the past three years. The pipe insulation on the lower and the intercooler grills on the last photo are only used in the coldest months.
__________________
60 mpg hwy highest, 55+mpg lifetime
TDi=fast frugal fun
make NOx not Carbon


"I worked on the wiring to see if I could get the alternator to charge. The stud was loose and I accidentally let the white smoke out of the box... Alternators, among other things, run on white smoke. Once you let the white smoke out they no longer work!" planejob

Last edited by COcyclist; 04-18-2014 at 11:01 AM..
  Reply With Quote
The Following User Says Thank You to COcyclist For This Useful Post:
aerohead (04-19-2014)
Old 06-24-2014, 12:32 AM   #5 (permalink)
Not banned yet
 
deejaaa's Avatar
 
Join Date: May 2010
Location: Baytown, Texas, close to Houston
Posts: 875

getto - '02 Volkswagen Jetta GLS TDI
90 day: 53.82 mpg (US)
Thanks: 405
Thanked 255 Times in 204 Posts
FWIW, i have removed the lower and upper grille blocks and the rear boxed section. i logged 64 2 tanks ago and 59 the last, with the mods removed. not sure how that worked.
i have been thinking about changing the front bumper, sort of like this. (my crude paint rendition)

using expanding foam and fiberglass.
__________________
02 TDI Jetta- 5 sp: Cooper CS5 at 50 psi, UltraGauge, ventectomy, rear air shocks, mufflerectomy, LED plate light, upper fiberglass grille block, flat wheel covers, front/rear DVR, front lower pan, front fairing.
93 Chevy CrewCab 6.5 TurboDiesel, GearVendor OverDrive, 4L80 w/ full manual control. Now my DailyDriver


Quote:
Originally Posted by Daschicken View Post
....As of lately, I have started taking the bus to the other campus, because there are more people in space than there are parking spots over there.....
  Reply With Quote
Old 06-24-2014, 03:51 PM   #6 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 8,667
Thanks: 11,175
Thanked 4,590 Times in 2,576 Posts
nose

Hucho was involved in the aerodynamic optimization of the original Golf/Rabbit,Jetta,etc.. The nose of the production 1st-gen VW has almost as low a drag as the 'optimum' nose tested on the car.
Hucho mentions that we ought to focus on the rear of our cars,to reduce or eliminate the flow separation which is responsible for the lion's share of drag.
Here is the 'long-tail' VW 'Flow' body of 1981,with Cd 0.14.You can see that it's nose is nothing remarkable,although it does have a complete boat-tailed rear.
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/

Last edited by aerohead; 06-24-2014 at 03:51 PM.. Reason: add photo
  Reply With Quote
The Following 3 Users Say Thank You to aerohead For This Useful Post:
Cd (10-09-2014), COcyclist (03-10-2015), deejaaa (06-24-2014)
Old 06-24-2014, 05:49 PM   #7 (permalink)
Not banned yet
 
deejaaa's Avatar
 
Join Date: May 2010
Location: Baytown, Texas, close to Houston
Posts: 875

getto - '02 Volkswagen Jetta GLS TDI
90 day: 53.82 mpg (US)
Thanks: 405
Thanked 255 Times in 204 Posts
Quote:
Originally Posted by aerohead View Post
Hucho was involved in the aerodynamic optimization of the original Golf/Rabbit,Jetta,etc.. The nose of the production 1st-gen VW has almost as low a drag as the 'optimum' nose tested on the car.
Hucho mentions that we ought to focus on the rear of our cars,to reduce or eliminate the flow separation which is responsible for the lion's share of drag.
Here is the 'long-tail' VW 'Flow' body of 1981,with Cd 0.14.You can see that it's nose is nothing remarkable,although it does have a complete boat-tailed rear.
i've read that here but i am hard headed. i realize it won't make much if any diff on the front so i will focus on the rear. i have the template but am still overwhelmed at the thought of tackling that area.
i would like to see a real picture of a MK4 with some rear mods that work.
__________________
02 TDI Jetta- 5 sp: Cooper CS5 at 50 psi, UltraGauge, ventectomy, rear air shocks, mufflerectomy, LED plate light, upper fiberglass grille block, flat wheel covers, front/rear DVR, front lower pan, front fairing.
93 Chevy CrewCab 6.5 TurboDiesel, GearVendor OverDrive, 4L80 w/ full manual control. Now my DailyDriver


Quote:
Originally Posted by Daschicken View Post
....As of lately, I have started taking the bus to the other campus, because there are more people in space than there are parking spots over there.....
  Reply With Quote
Old 06-24-2014, 06:10 PM   #8 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 8,667
Thanks: 11,175
Thanked 4,590 Times in 2,576 Posts
Mk4

Quote:
Originally Posted by deejaaa View Post
i've read that here but i am hard headed. i realize it won't make much if any diff on the front so i will focus on the rear. i have the template but am still overwhelmed at the thought of tackling that area.
i would like to see a real picture of a MK4 with some rear mods that work.
Here,VW has pushed the roofline up to the 'Template' for the 1-liter car series.It's truncated,so they pay a fine on drag,but it's below 0.19,not shabby.
It's nose is quite blunt in elevation,although has nice side curvature.
Again,the 'secret' is in the aft-body elongation.
The MK4 would see similar drag.

With additional length we get into Cd 0.15 territory,just as Hucho reports
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/
  Reply With Quote
The Following User Says Thank You to aerohead For This Useful Post:
COcyclist (10-14-2014)
Old 10-09-2014, 07:18 PM   #9 (permalink)
Burning oil to move air.
 
Join Date: Aug 2011
Location: Valencia (Europe)
Posts: 126

ausiasmobil - '06 Seat Leon 1.9 TDI Reference
90 day: 40.22 mpg (US)

EcoTxec - '99 Skoda Octavia 1.9 TDI 110 cv Laurin & Klement
90 day: 52.85 mpg (US)
Thanks: 92
Thanked 37 Times in 25 Posts
very interrsting my car that shares VAG A4-platform with your Jetta.
1999 Skoda Octavia 1.9 TDI 110 cv Laurin & Klement Gas Mileage (EcoTxec) - EcoModder.com
with less aeromods and also a taller gear it does at ease 3.3 to 3.4L/100kms long trips of 700 kms. Speeds between 90 to 100 km/h.
but conmute trips and air conditioning and also hw speeds of 120 km/h doesn.t permit to do full tanks under 4.3 L/100km so easy.

what engine dow yo have in Helga ALH 90 cv VE rotary pump? or is it a 90 cv TDI with wastegate turbo? or maybe a PD 101 engine?
__________________


Sold:

  Reply With Quote
Old 10-09-2014, 08:13 PM   #10 (permalink)
Not banned yet
 
deejaaa's Avatar
 
Join Date: May 2010
Location: Baytown, Texas, close to Houston
Posts: 875

getto - '02 Volkswagen Jetta GLS TDI
90 day: 53.82 mpg (US)
Thanks: 405
Thanked 255 Times in 204 Posts
Quote:
Originally Posted by ausias View Post
very interrsting my car that shares VAG A4-platform with your Jetta.
(1)1999 Skoda Octavia 1.9 TDI 110 cv Laurin & Klement Gas Mileage (EcoTxec) - EcoModder.com
(2)with less aeromods and also a taller gear it does at ease 3.3 to 3.4L/100kms long trips of 700 kms. Speeds between 90 to 100 km/h.
but conmute trips and air conditioning and also hw speeds of 120 km/h doesn.t permit to do full tanks under 4.3 L/100km so easy.

(3)what engine dow yo have in Helga ALH 90 cv VE rotary pump? or is it a 90 cv TDI with wastegate turbo? or maybe a PD 101 engine?
(1)never heard of that place. your local economy gurus?
(2)what gear, L/kms don't mean anything to me. can kind of figure out km/h, but that's it.
(3) don't know who Helga is either. car has an ALH.

__________________
02 TDI Jetta- 5 sp: Cooper CS5 at 50 psi, UltraGauge, ventectomy, rear air shocks, mufflerectomy, LED plate light, upper fiberglass grille block, flat wheel covers, front/rear DVR, front lower pan, front fairing.
93 Chevy CrewCab 6.5 TurboDiesel, GearVendor OverDrive, 4L80 w/ full manual control. Now my DailyDriver


Quote:
Originally Posted by Daschicken View Post
....As of lately, I have started taking the bus to the other campus, because there are more people in space than there are parking spots over there.....
  Reply With Quote
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com