Post your "Failure Stories" and lessons learned from unsuccessful modifications
 

I wonder if ecomodder would benefit from an "Unsuccessful Stories" or "Less Successful Stories" forum to combat the effects of publication bias. In particular I'm thinking about A-B-A tests like the smooth wheel cover wiki - Smooth wheel covers - EcoModder.... we know that there should be a lot of variability in the results depending on the stock wheel covers...

Separately, the "what-not-to-do" lessons in materials are often quite valuable: i.e.:

• Don't violate 15° approach angle with rigid fixed air dam materials.
• Don't use dark-painted coroplast if dimensional stability matters.
• Don't leave tape gum on the car in the sun.
• Don't use polyester resin over foam.

There are some other areas where encouragement of failure reporting may be helpful:

• Adverse effects of over-inflation.
• Over-heating resulting from grille over-blocking.
• Unintentionally poor visibility resulting from poor mod design.
• Mods that failed local safety inspection requirements.

Is it a good idea, or unnecessary?

My tiny mod, the wing-shaped antenna stalk, generated a couple of fails:
- Make sure your mods don't deform under mild pressure e.g. circumstances you can expect in real life. (winglet mark 1 deformed and split open)
- Don't ever try to speed up glue bonding in an oven, not even at very mild temperatures, unless all materials used explicitly need that kind of treatment. (winglet 2 deformed just enough to be useless in the process)
- Make sure that whatever you fix to your car is secure enough to not come off on the highway. (winglet 3 flew off and landed on the highway, making a big rig behind me slam the brakes - for less than 1 gram worth of clear plastic... !!! ???)

You should take extra care with pizza pans and other aero covers. Rule of thumb; they should be fastened so sturdily that you cannot pull it off again even when using full force. Every square inch can generate a pound of force pulling on it at highway spreeds.
Aerial winglet 3, though tiny, was so tight that I had to use a lot of force to push it over the antenna stalk. It came off at 55 mph nonetheless. But I was happy; it did prove my point that the drag on the stalk was substantial, and so would any mod reducing that.

Don't put a hair drier under your hood. It might cause a fire. It did not on mine, but it did not heat the engine either, at least the effect was minimal. A block heater might work. A hair drier though wastes just too much heating everything else under the hood but the engine.
It did melt the snow on the hood, but I can just wipe that off anyway.

"LESSONS LEARNED...the hard way"?

Front top grill block not ziptied down enough. Parachuted up causing major drag on the highway. Of course i can't see at all over the hood! Unknowingly lost about 10%mpg for 100 miles.

" Don't use dark-painted coroplast if dimensional stability matters. "

Christofoo, what do you mean by this ? Do you mean coroplast that has dark paint on it, or coroplast that is already a dark color, such as black coroplast ?

And dimensional stability ? Can you expand on that please ?

Thanks

Coroplast is polypropylene, it softens and warps in hot sunny conditions unless the final color is very light to keep the surface temperature down. To my knowledge, kach22i had the most striking example of this.
http://i184.photobucket.com/albums/x...psfd11bc4d.jpg
http://ecomodder.com/forum/showthrea...tml#post375743
I've had the same experience with my passenger-side Corolla wheel-skirt, but not the driver's side skirt, just because I park facing east, passenger-side in the sun.

There are applications where a little warping is not important, i.e. I haven't had a problem with the black coro on my upper-grille-block.

I imagine A "Failures" Thread or Forum might be beneficial, As long as it does not get out of hand.

One of the pizza pans fell off my Father's caravan while I drove. I could see it close to coming off when I was parked at the stop before it fell off. I didn't think it would come off and we were in a rush, I didn't say anything about it to my Father. (Edit and note - I didn't say anything about it to him at the time, Not until after it fell off.) I had parts to put it back on properly, Too.

I think a whole new forum is probably a bit much (there won't be a lot of threads).

But I suspect a "lessons learned from failure" thread in EcoModding Central would get contributions. I think you just started it. :) I'll move it over and edit the title.

Failure? I have no idea what you're referring to. I don't know about the rest of you, but everything I do works perfectly the first time [insert sarcasm].

So far just changing the front spoiler into an air dam. I had it rite the first time when I tilted out the conveyor material at the bottom.
It worked really well but when I added side skirts I figured air dam and it dropped mpg 1.5its still that was 2 months later because I threw away the bracketts required to angle it forward at the bottom. Air dams work for some people but my sephia is pretty aero and it is just a big speed brake infront of the bumper now.

Oh forgot another one for all ya pizza pan modders. first go of it back in 1995? I tried pizza pans on my Metro xfI It was simple job because the car had aluminum wheels and lip was close enough to drill n tap 3 holes and done.
Did that and drilled each hub to match the stem and pulled them through.
The holes wer too large to hold stem still and too small to prevent movement.
But just rite to act like mini saws cutting through the valve stems slowly unnoticed untill one failed. Non issue I thought if was a road hazzard and loaded on spare.
At tire shop 2 days later I got to pay for 4 dismount replug and remounts.
A simple and stupid thing but it could have killed me too.

On subject of poorer-grade gasoline:

Before I get into this far, I will mention that there's a local gas station which sells pure gas but on the few occasions we got it, It ran worse for a lawnmower and even the van and their ethanol-grade gas was cleaner.

Anyway, I don't know for sure which grade of gas the gas station attendant pumped into the van the last time (I did say "Regular" and not "Pure Gas" but he seemed to be in a rush) but as of late the ScanGauge has been reading that we've been getting 16 MPG or so in it even with the way I drive, We should be getting over 20 at least. The ScanGauge II hasn't been calibrated for a long time, So I have no idea if it's quite accurate but the gas we got from that one station did go through the car faster according to the fuel gauge.

Also, My Mother used to get gas at that same small station and was getting about 17.5 in her Dodge Caravan which is a 3.3 litre, *According to her on-board FE meter which may or may not be quite correct*. I recently pumped gas into it from Sheetz instead and so far, The on-board average meter (Since a stop near the gas station to calibrate the odometer and F/E meter) says the van got over 18 so far.

So, Keep fuel quality in mind.

EDIT - The section between the asterisks was added at this time.

Coroplast isn't really tht stiff and will sag if it isn't supported enough on the underbody. Mine started scraping after about 80 miles on the highway and I ended up removing everything after just a few hundred miles. Version 2 is much smaller than the first attempt, only for the rear bumper and much more rigidly attached. I haven't had any problems after several thousand miles.

Removing the Pizza Pans was quite a drag and caused me to hold down the accelerator pedal more. Putting them back on helped, Though I don't think the van is getting quite the same FE as it was just yet.

Yesterday another pizza pan fell off. The two which remain are attached in a way as to not modify the hubcap, So perhaps I should modify the hubcap to attach them or put something else on the hubcaps that won't fall off so easily.

Also, This is a lesson for me: Driving at night. Another thing which happened yesterday is I took a long time to get out of whole foods; I took nearly an hour to eat my small meal starting at about 5:09 PM EST (I chewed my food a lot and sampled olives!) and then I had a long detour on the way home (Which is where the pan fell off,) And then before long I was driving at night. I went below the speed limit in a lot of places and on a road near home I was going at about 25.

By the time I woke up at about 10 AM this Tuesday morning, My arms were tired and my eyes were tired and my legs were tired. I'm not saying negative things about driving at night, Just that it was much more difficult to do than driving in the day and perhaps others are more used to it, But I'm not and it tired me.

The smooth wheel covers that have failed on my car are all because the stupid springs that hold them on are crappy. I think I've lost five or six, and my wife lost one? The stainless steel moonies have decidedly rust-prone steel springs, and those failures cost me over $125.

I tried smoothing over the trough along the windshield at the 'A' pillar and it did absolutely nothing.

My rear belly pan sagged and "kited" and fell off and dragged on the road, and I pulled it the rest of the way off.

The rear wheel strakes have been beat up a fair bit, and right rear one got knocked off on a deep dip at an intersection with four people in the car. I retrieved it and repaired and reattached it, and it has been fine.

The first set of LCD monitors I used failed in hot sunlight. And I've had at least 3 video cameras fail, one because the wiring chaffed on the steering column and shorted out - which blew a fuse and the car would not restart, and I had to have it towed. That was embarrassing and a pain...

But, I've saved probably well over $1,500 on gas, so it has been well worth it.

Knock knock

who's there.

WAI with too much grill block. Thought I was going to be lose the engine.

How avout driving without a thermostat for the last 1000+ miles? Is there a emoticon for beating your head on the wall?

Could you explain this more? I'm curious.

I see a few people are having problems with aero hub caps.
My aero hub caps have worked great for more than a year now, several cross country trips later.
http://ecomodder.com/forum/showthrea...eel-22003.html

I've been looking over that Mercedes with its reputed Cw of 0.23 to look for details that are different, as from a distance it looks like nothing special is going on.
On of those details was that the A pillars have a protruding edge, as if the glass has sunk half an inch down.
Then there's the 2015 Jazz, which (as a hybrid) claims to get 80+ mpg. It has that same feature...

So (at least) 2 cars that get better FE than expected have protruding A pillars, or 'deepened' front windows.
What then makes that so good?
You'd expect that it would be good to make the air roll smoothly over the A pillar. These designs, and the trough you covered, all make it less smooth, but they work.

In the Mercedes smoke test you can see the air still rolls over the A pillar, apparently the edge cannot prevent it completely. It makes a sharp radius and gets turbulent. It does not look particularly good, something you want to avoid.
The flow over the roof is very smooth indeed.
I think anything that can lead more air over the roof instead of curling over the A pillar would lower air resistance. Might even add a small ridge to the front of my A pillars one day...

When your mod doesn't do what you expected, it may just be pointing out another direction to follow.

My best “failures”:

Using aluminum sheeting for a belly pan:
I found aluminum is not the best material for a DIY belly pan, especially a first attempt. It is expensive, fairly heavy in 0.060 thicknesses, still needs supports, can develop shakes and rattles, and without specialized tools such as an English Wheel, rollers, brakes, and shears it seriously limits design. With better tools and more experience I think aluminum could be a great choice for a “second version” belly pan material, just take the first version pan and copy it, making sure to adequately dampen rattles.

Belly pan under exhaust:
I had major issues putting belly pan materials under my exhaust, even using metal that could withstand the temperatures and maintaining adequate clearance. It turns the gap between your car and the pan into an oven. If done near your gas tank it can heat your tank up and start boiling off the fuel. Even not near your gas tank the pan trapped hot air under the car and heated the cabin from below. Using aluminum or other bare metal with high reflectivity on the top and no emissivity below makes this situation worse. Cutting out 50+% of the material below the exhaust was not enough to prevent this from happening.

Using expanding foam for removable grill blocks:
Expanding foam will continue changing shape for quite a while even after the outside is hard. It will grow, shrink, warp, etcetera. Note I did not incorporate any internal support in my piece, I have seen others that inserted dowels or similar and claimed this helps.

Grill block when air can bypass radiator:
If the air can just blow under the car or around the radiator it will seriously limit the amount of grill you can block without heating problems. Simply plugging these holes will let you block more grill and still maintain lower temperatures.

First, how many modifications have I actually gotten around to attempting? I tried putting marine wrap on my Forester hubcaps and that seemed doomed. I made a marine wrap grill block and I think that it was too warm. I wish that I had thought of this a week or two ago, driving to the bakery before sunrise it would have been as cold out as 28°F, although I definitely would have needed to remove it for my drive home. I tried cutting coroplast to fit over my fog lights, but just messed up that. I removed my fog lights and sprayed Great Stuff in the hole, not realizing that Del Sol liked having it attached to tin foil. I removed the roof rack cross members, but removing the rails is nearly impossible. I bought a pizza separator, but bought my Civic before tapping out the lug nuts to attach the disc.

I made an air dam, but tried to shrink it to fit better and melted it. I bought pizza separators, but the zip ties attaching them to my wheels started breaking. I pulled the power steering, but I had just driven to the second supplier that was supposed to have the parts to loop my steering the day that my father passed passed away.

Is that all that I have done to Chorizo? That is not much!

Hmm... Well I made the insight get hot once or twice when testing the limits of the grill, and seeing how much I could block. I also had a prototype belly pan (Coloplast) come lose on the highway. Other then that, nothing I can think of.