Where are the aero-modders?

Hey everyone.

Some reading over at ecomodder.com has me wondering why no one goes all out making an alh TDI into a max mpg machine. I am tempted myself. Maybe its because without even trying we all get 45 or better...ha!

I decided to start with a simple grill block. Came out pretty good I think. Used a piece of black coroplast I found laying around at work and some small brackets. For those unaware of this mod, the point is to smooth airflow over the car and thus reduce the amount of aerodynamic drag. Second benefit is much improved warm up times for the engine, also a huge benfit to FE of course.



I also pulled the upper grill and blocked it also, with a small rectangular box feeding directly into the engine air intake on the upper right side. Don't have a good pic of this at the moment. Need to some rubber bulb seal along the front hood line to finish everything off.



Before anyone yells at me, I know, the 17's have to go. Soon I'll put on the stock 15's with winter tires, and come spring I will invest in some lightwieght 16s and slightly oversized LRR tires.
Besides that I may go as far as making rear wheel skirts and doing a passenger side mirror delete. A rear deck-lid extension like you see on bonneville salt flats max speed vehicles would be awesome also, but I don't have those kind of fabrication skills.

Something along these lines could yield an easy 70mpg from the most frugal hypermiler on these forums, I'm sure!

http://www.blogcdn.com/www.autobloggreen.com/media/2007/08/fusionhydrogen999_2.jpg

So who else has gone down this path? Let's see some photos of your aero-mods!

pretty vast one here http://forums.tdiclub.com/showthread.php?t=147718

shizzler said:

Something along these lines could yield an easy 70mpg from the most frugal hypermiler on these forums, I'm sure!

Click to expand...

Why would I want to drop my competitive fuel mileage down to 70 mpg?

uhm, ok.

Thanks for the link slave2school, but that thread seems to be mostly conjecture. I'd like to see actual modifications people have done to their TDI's in the interest of obtaining better mileage. Perhaps if we don't limit ourselves to just external aerodynamics mods there will be more.....?

Lug nut, you realize of course that you are in the 0.01% of TDI owners that can achieve such mileage. Did you do any modifications to your vehicle or is that all from hypermiling? Impressive nonetheless.

When you check over on ecomodder.com or gassavers.org you find all sorts of people modifying their rides for improved FE. With the way people always complain about losing 1 or 2 mpgs in this forum, I'd think there would be more who are interested in the simple tweaks that can net one or two also.

shizzler said:

uhm, ok.

Thanks for the link slave2school, but that thread seems to be mostly conjecture. I'd like to see actual modifications people have done to their TDI's in the interest of obtaining better mileage. Perhaps if we don't limit ourselves to just external aerodynamics mods there will be more.....?

Lug nut, you realize of course that you are in the 0.01% of TDI owners that can achieve such mileage. Did you do any modifications to your vehicle or is that all from hypermiling? Impressive nonetheless.

When you check over on ecomodder.com or gassavers.org you find all sorts of people modifying their rides for improved FE. With the way people always complain about losing 1 or 2 mpgs in this forum, I'd think there would be more who are interested in the simple tweaks that can net one or two also.

Click to expand...

Good luck! Let me know when you find some modified TDIs.

There's threads here on Ernie's NB wing
http://www.max-mpg.com/html/tech/main.htm

shizzler said:

Lug nut, Did you do any modifications to your vehicle or is that all from hypermiling? Impressive nonetheless.

When you check over on ecomodder.com or gassavers.org you find all sorts of people modifying their rides for improved FE. With the way people always complain about losing 1 or 2 mpgs in this forum, I'd think there would be more who are interested in the simple tweaks that can net one or two also.

Click to expand...

My cars are a unmodified as previously owned car can be. Replacement tires, brake pads, shocks, and other wear items, but no changes solely for fuel economy gains. that is unless you consider re-constructing a TDI wagon from a wrecked TDI wagon a modification.
All my 'tweaks' are between my ears and in my ankles. No labor, no parts, no installation, no cost, instantly transferable to another vehicle, and an on-demand 50% improvement?
Enjoy you grille block.

No need to get testy. I do enjoy my grill block, thanks. The car heats up a couple miles sooner on the highway, and though I can't prove whether any real aerodynamic gain is realized, my average FE is up 1-2 mpg.

Enjoy your painfully slow driving style (I am assuming here)...

While I don't know your typical driving mix of highway/city, you do realize that if your car were more aerodynamic, you could realize even better economy... right? Don't get me wrong, driver adjustment is obviously the most effective and prudent method of improving FE. But why not help yourself out with some simple tweaks?

btw, my commute is 24 miles of mandatory 70mph traffic, or you get pushed off the highway. So perhaps there is more incentive for me to pursue aero gains.

I don't have an A4, but my A3 got coroplasted big time. Notice the passenger mirror block off plate.



It should be noted that the car should be re geared to take full advantage of aeromods.

So what kind of difference do you see with those mods on an A3?

MrPolak said:

So what kind of difference do you see with those mods on an A3?

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I don't know. I do not have a good baseline to compare to and the ScanGauge is not working properly on my TDI.

Lug_Nut said:

All my 'tweaks' are between my ears and in my ankles.

Click to expand...

You forgot to mention your iron butt
Which remind me I need to pick your brain as my commute has changed.

shizzler said:

...you do realize that if your car were more aerodynamic, you could realize even better economy... right? Don't get me wrong, driver adjustment is obviously the most effective and prudent method of improving FE. But why not help yourself out with some simple tweaks?

Click to expand...

Right on. Aerodynamics is a neglected aspect of modding a TDI for good economy. Going slow may net a few dedicated people some impressive numbers, but being able to go North American freeway speeds -- and get in sight of 60 mpg -- would really turn some heads.

Here's a few random ideas as to why we don't see more aero-modding of TDIs... all strictly IMO:

1) Aerodynamics itself can be tricky and non-intuitive. Who'd look at a Kamm tail and think it was the low-drag solution?

2) Even well-executed aerodynamic features, designed into the bodyshape from the beginning, look odd and geeky to the average eye. (Witness widespread distaste for the look of the Insight and the Prius.)

3) Many (and most effective) aerodynamic features *have* to be designed into the bodyshape from the beginning. Getting a teardrop profile on a Golf or Jetta requires big changes to lots of bodywork.

4) Aero mods, even small ones, require bodywork and finish skills. Most of us TDIers are either amateur or pro wrenches, not bodyshop guys. Speaking for myself, an afternoon up to my elbows in engine parts is Good Times to me. An afternoon of wet sanding, not so much.

5) And badly done aero mods added on by hobbyists with questionable bodywork skill look... well... I'll let the Ecomodders site speak for itself, and just remark again that one of the things some people like about the VW TDI lineup is that they are practical, ordinary-looking cars that happen to get great mileage. Stealth green, if you will.

But with all that said, I'm still eager to learn of any tips or tweaks that might make my Golf more efficient at highway cruise speeds (where it spends most of its life). I think driver skillz and right-foot discipline fade in importance when we're talking about steady-state 65-70 mph operation. I suspect that the most fruitful areas for aero-modding will be around the front end, such as grill blocks and lip spoilers, under the car such as smooth bellypans, and around the rear edges such as spoilers and wings that aid in clean separation. I hope this thread attracts attention from folks that actually know stuff about these subjects!

Eddy

Lug_Nut said:

My cars are a unmodified as previously owned car can be. Replacement tires, brake pads, shocks, and other wear items, but no changes solely for fuel economy gains. that is unless you consider re-constructing a TDI wagon from a wrecked TDI wagon a modification.
All my 'tweaks' are between my ears and in my ankles. No labor, no parts, no installation, no cost, instantly transferable to another vehicle, and an on-demand 50% improvement?
Enjoy you grille block.

Click to expand...

Yeah.. and thanks for making me feel kinda guilty when I hammer by you on Rt 2 every night!

very cool

shizzler said:

Hey everyone.

Some reading over at ecomodder.com has me wondering why no one goes all out making an alh TDI into a max mpg machine. I am tempted myself. Maybe its because without even trying we all get 45 or better...ha!

I decided to start with a simple grill block. Came out pretty good I think. Used a piece of black coroplast I found laying around at work and some small brackets. For those unaware of this mod, the point is to smooth airflow over the car and thus reduce the amount of aerodynamic drag. Second benefit is much improved warm up times for the engine, also a huge benfit to FE of course.

I also pulled the upper grill and blocked it also, with a small rectangular box feeding directly into the engine air intake on the upper right side. Don't have a good pic of this at the moment. Need to some rubber bulb seal along the front hood line to finish everything off.

Before anyone yells at me, I know, the 17's have to go. Soon I'll put on the stock 15's with winter tires, and come spring I will invest in some lightwieght 16s and slightly oversized LRR tires.
Besides that I may go as far as making rear wheel skirts and doing a passenger side mirror delete. A rear deck-lid extension like you see on bonneville salt flats max speed vehicles would be awesome also, but I don't have those kind of fabrication skills.

Something along these lines could yield an easy 70mpg from the most frugal hypermiler on these forums, I'm sure!

http://www.blogcdn.com/www.autobloggreen.com/media/2007/08/fusionhydrogen999_2.jpg

So who else has gone down this path? Let's see some photos of your aero-mods!

Click to expand...

anybody sell this stuff ready made? keep me posted on your progress.

Great Job!

tasdrouille said:

I don't have an A4, but my A3 got coroplasted big time. Notice the passenger mirror block off plate.

It should be noted that the car should be re geared to take full advantage of aeromods.

Click to expand...

Excellent work. how is it on economy so far? Can you buy any of this stuff for a beetle?

Here are two interesting ideas I saw while surfing:

www.nasa.gov/centers/langley/pdf/70816main_FS-1996-09-17-LaRC.pdf



http://www.fas.org/man/dod-101/sys/missile/row/shkval.htm
"The solid-rocket propelled "torpedo" achieves high speeds by producing a high-pressure stream of bubbles from its nose and skin, which coats the torpedo in a thin layer of gas and forms a local "envelope" of supercavitating bubbles."

Lightflyer1 said:

Here are two interesting ideas I saw while surfing:

www.nasa.gov/centers/langley/pdf/70816main_FS-1996-09-17-LaRC.pdf



http://www.fas.org/man/dod-101/sys/missile/row/shkval.htm
"The solid-rocket propelled "torpedo" achieves high speeds by producing a high-pressure stream of bubbles from its nose and skin, which coats the torpedo in a thin layer of gas and forms a local "envelope" of supercavitating bubbles."

Click to expand...

I think if you where going about 500+ MPH, it would be a fantastic idea to try.

There was someone here who streamlined their car. Built some kind of frame around it with some kind of plastic around it. Closed in the wheel wells too. Ugly as I recall, but ISTR it worked. I can never find the link to the picture when I want to.

Lightflyer1 said:

There was someone here who streamlined their car. Built some kind of frame around it with some kind of plastic around it. Closed in the wheel wells too. Ugly as I recall, but ISTR it worked. I can never find the link to the picture when I want to.

Click to expand...

http://forums.tdiclub.com/showpost.php?p=1610486&postcount=178

Must have got the idea from Back the the Future

That is it!

Long time since I really made any progress. But I'll bump this thread to see if theres any more aero modders out there.

Recently smoothed out my front and rear ends underneath:




I just did this the other day:

Looking at grill blocks and such makes me remember my first car. It had an adjustable grill block from the factory. Worked like a window shade and was adjustable via a cable from the driver's seat. Any guesses?

Son.. that's some mercilessly ghetto-fab work! But if it's functional, great!

I hope you have been recording incrementally as you go?

Check out this site..............

http://ecomodder.com/

interesting to poke around and see some of the older cars that used gas saving ideas that folks are coping today...

dr61 said:

Looking at grill blocks and such makes me remember my first car. It had an adjustable grill block from the factory. Worked like a window shade and was adjustable via a cable from the driver's seat. Any guesses?

Click to expand...

What kind of car was that? I wish modern cars had one.

I have no intention of putting a wing the size of Ernie's on, but would acquiring a turbo model's wing off of another Beetle and installing it on mine help out at all? I wouldn't mind putting a nice little wing on if it yields 1-2mpg.

nicklockard said:

What kind of car was that? I wish modern cars had one.

Click to expand...

1958 Volvo 444!

sweetjeep said:

Son.. that's some mercilessly ghetto-fab work! But if it's functional, great!

I hope you have been recording incrementally as you go?

Click to expand...

HA, yeah. But it's under the car so who cares.

While I record my mileage for every tank, its impossible to assign value to any single mod since I often do a few at a time and have multiple confounding factors. Carrying kayaks around, taking pieces on and off, weather changes, switching to pure biodiesel, and worst of all 2-3 weeks per tank make accurate measurements of benefit difficult. All I really care about is making my FE trend positively upwards. After a couple more mods I think I am going to try for an all out best tank....

You can count me an aeromodder. Pictures of my car can be found:
http://cid-acb1f13bac776768.skydrive.live.com/browse.aspx/seatti
I dont mind the looks, but the overall economy figures.