Looking for a way to better diffuse the light from your DIY LEDs? Consider the chop-top approach.

Purpose: Allow a wider diffusion pattern on your LEDs

The way to go about this is to clip off the top of the led and grind it down so that it’s nice and flat. Check out these comparisons.

Stock LED:

Chopped, notice the missing super-bright spot:

The power in your car is not free, it comes from the alternator and is a product of the huge amount of drag that this electrical generator puts on your car’s engine. I chose to begin my (unfinished) quest for LED lighting by converting my dome light to LEDs. It make be a modest start but it looks great and I’ve recieved many comments on it, even from some outside of the car enthusiast world. It seems much harder than it is, so don’t be intimidated if you’ve never done anything of the sort before.

Purpose: To cut down electrical loads on the charging system.

Time: 1 hour

Tools:
- Soldering Iron
- Knife

Supplies:
- LEDs (I used 15 10,000 MCD ultra brights)
- Resistors (100 ohm for this project)
- Some perf board (4 bucks at radio shack)

This is my awful demonstration of how the circuit should go. The resistor is crucial! I blew up one of these LEDs once and a flying chunk but a nick in my living room wall.

Grab your dome light outta the car. Mine was already out for randomness’s sake. Make yourself a little drawing to see how big the perf board should be cut.


Smash it into shape.

Start sticking the LEDs in. You want to line things up so that you’ll be able to tie all the negative sides together to go to the ground and the positives together in bunches of three so that each three can go to a resistor.

Look at it and be like, that’s hella sloppy. I just tied the four on the one end together and called it a day, in the end I soldered that straight onto the lead in the dome light housing.

All in!

Soldered completely.

Test wiring, notice the resistors are in also, don’t forget these!


All done but not mounted!

Mounted up on the car. I had to cut the board a bit to get the screw in there. Night pictures ought to be done but you can’t really see anything, just trust me and get it done! You can also use amber LEDs if you are into that look.

Name: Dan Kroushl
Occupation: Professional Slacker (You don’t really need to know, do you?)
Weapon of Choice: 1992 Honda Civic VX (Stock)

For months Dan has been a bit of an icon around ecomodder.com and I thought it fitting that he receive proper mention here and he has driven so many people to look for new heights in their quest for gas mileage.

When Dan first came to the ecomodding game he was making 50 MPG tanks in his Del Sol S. This doesn’t seem like much now, but at the time it was amazing. In the end Dan managed to hit mid 60s in the Del Sol and is now pushing past the 70 MPG barrier in his Civic VX.

You might not know Dan, but he’s already become a mini-star on the internet for his contribution to the quest for fuel economy. You can check him out on the Toyota website here where his efforts with four partners set a world record for fuel economy. This has since been topped, but who knows how long any of these records will last?

However you look at it, Dan’s really paved the way for great fuel economy; first in the Prius and now in his fifteen year old Civic VX.

In order to share a little bit about his technique with everyone, I asked him a few questions about his adventures with hypermiling.

Ben: How did you first learn to hypermile?
Dan: I started hypermiling in 1985 when I bought the CRX HF. I did just what made sense to do to save fuel. Turns out that those things match up pretty well with what now turns out to be accepted hypermiling techniques.

Ben: What difference has the superMID made in your driving practices?
Dan: It helped the Prius Marathon team learn to go from 107ish to up to 120MPG. It (and the scangauge) is the single best investment in FE improvement. I guesstimate that it was good for 20% improvement in the Del Sol FE, from 55 to 65 MPG.

Ben: How does your Civic VX compare to the Prius in terms of comfort, usefulness, and FE?
Dan: The VX can carry up to 5 passengers, but more cramped than the Prius. The Prius has much more cargo room, quieter, smoother ride and has A/C. The VX gets much better highway FE and similar city FE if driven properly. The VX was about 1/10th the price of the Prius.

Ben: Do you see any obvious advantages or disadvantages to driving the VX?
Dan: The VX is the highway cruiser. The Prius is much easier to drive in the city, EV mode being very useful.

Ben: Do you feel cooler when you drive the Honda?
Dan: I feel like a geek in both. But if I had the rust repaired and a nice new shiny coat of red paint, I would feel cooler in the VX.

Ben: Could you give us a short description of your route and common segment FE?
Dan: My commute is 40 km (25 miles) each way. Ten km city type driving, then 20 km highway in 45-55 MPH zones and then 10 more km of city type driving. Lots of hills. [Dan regularly gets 75 MPG on his commute.]

Ben: What are your three biggest FE driving tips?
Dan: Get a SuperMID or Scangauge, drive such that you don’t need to use your brakes, leave early and take your time, the speed limit is the maximum, not the minimum.

Ben: Three biggest modifications?
Dan: SuperMID/Scangauge, LRR tires, full belly pan.

Ben: For all those driving a non-FE car, how hard was it to pick up the VX?
Dan: Just watch ebay for VX’s. You want a 49 state version, not the CA version. Be prepared to do some repair work to get it in top shape. Most likely it will need an O2 sensor for $315 at Autozone [You can get these much cheaper if you have a warning that you will need it!]. Other likely repairs will be axle replacement and front rotors as they tend to warp. Most have rust at the rear wheel wells but not to worry, FE isn’t effected that much by rust. Don’t be too concerned about high mileage, Honda’s last forever. If you do find one on ebay, try to get a test drive before bidding.

If you can’t find a VX, a CX will do quite nicely.

For those interested, here’s his gaslog with the VX:

Thanks very much to Dan for sharing with us, hopefully his example will lead us that extra little distance to superb fuel economy!

Doing a tune up? Replacing spark plugs? Just wanting to check things out? While you’re at it consider indexing your spark plugs. This is one of the few ignition modifications that can make a very small difference in engine performance. As said by the folks at Advance Auto Parts: “Real-world power gains vary. Some engines or combinations respond differently than others. In fact, all engines will pick up power, but some gains will be more dramatic than others.In the end, it can’t hurt to index the spark plugs. This can contribute to superior engine efficiency and improved economy.” So, no promises, but it can’t hurt!

Purpose: Indexing the plugs allows the flame to spread more uniformly through the combustion chambers in the individual cylinders. I am certainly not about to claim a plethora of scientific knowledge on the subject but I’ve seen many dyno charts supporting the theory and have thus accepted the idea that it’ll help. It’s really not too much extra effort on top of replacing the plugs, so what the heck.

Time: 20 minutes

Tools:
- Socket Wrench
- Spark Plug Socket
- Extension

Supplies:

1. Go to the parts store and buy yourself some new spark plugs, preferably Denso U-Grooves or NGK V-Powers (basically the same). They’re the recommended stock replacement and generally used plugs; cheap and effective. Again, I do not profess to be a spark plug wizard.
2. Pop them out and take a look at how they get their name.


3. Mark with a marker the on the white part where the opening on the plug is. This will allow you to see where the opening it when the plug is in the head getting adjusted.

5. Go out to the car, yank your plug wires and then your old plugs.



6. Stick a new plug in and tighten it down and see where the opening is. On most cars you’ll want the opening facing the exhaust, but it’s different for everybody.
7. If it lines up perfectly stock, you’re lucky, if not, grab a copper indexing washer and throw it on the bottom of the plug and see how it works. There are different sizes of washers and all that to try and get the indexing right, so just mess around until you get it.

See if you can see how it’s lined up:

8. Once they are all indexed, slap everything together and be happy.

There are two methods of indexing, one is to buy lots of plugs and attempt to get lucky, the other is to use washers, take your pick. I chose to use washers rather than to try my luck. Less wasted gas driving to the store.

UPDATE: Because of the cost and relative hard-to-getness of the SuperMID (though it is awesome), I’ve been pointing people to a DIY open source project called the MPGuino, currently being worked on over at ecomodder.

The mecca of fuel economy is instantaneous feeback. With this you can tailor your driving to absolute perfection in terms of gas mileage. There is no way, none whatsoever, to realize what’s actually happening with some sort of instantaneous, accurate feedback. It also helps to have something that can log tanks, laps, and trips so that you can watch yourself improve or test various techniques and modifications.

The thing that makes the superMID special is that it works for cars that are obdII and pre-obdII alike. The other tool, the Scangauge, only works for cars running obdII electronics (most 1996 and newer models). So, when I learned that a Japanese man named Yoshi had created a device to monitor his Prius’s mileage, and that this device could be used on my 1991 Honda CRX, I was justifiably happy. With this little device I have done more than I ever could have imagined, and I will go into some function in a later argument.

In the mean time, if your car is fuel injected you may be able to use this little baby!!! Send me an email if you’re interested with your information and your car’s information and I’ll see what I can do in terms of hooking you up with one of these things. So far there are only three of us in North America that use them (how exciting)!

Purpose: To better monitor your fuel economy. A week with instantaneous feeback is like a year with tank to tank results.

Time: 1 hour

Tools:
- Wire Strippers
- Soldering Equipment (including heat shrink)
- Anything you might need to access ECU/under dash wiring

Supplies:
- MID and all install contents
- Some stranded wire
- Female/male end connectors

First thing’s first (a little homage to those who helped me get this thing going):

Thanks to Dan and Yoshi. To Dan for his dedication and the ability to hit over 99.9 mpg with the prius making this little device necessary. Thanks for all your help and for giving us the inspiration to know that we can get crazy numbers through driving technique and patience. To Yoshi-dono for building this awesome piece of equipment and for providing great support. I still can’t believe it came from Japan to the east coast of the US in only three days!

Now, before I start in earnest, just let me say, this thing is incredibly well designed. All the wiring is consolidated into a thin, pluggable lan cable that is very easy to work with and will make mounting a breeze! Yoshi kicks butt!

Procedure:

Here’s all the stuff you get. LAN cable, MID, black box.

Expose your ecu. Prolly the most difficult step, but mine is always exposed, so I win.

Figure out which spot on the fuse box will give constant power. You’ll want to power the MID from this spot so you don’t lose data when you engine off coast.

More glorious shots of the device. Notice the red wire coming off for power, will plug up to that wire you saw coming from the fuse box.

Spliced the MID ground into the other ground I use for junk.

All wired up. Yellow to an injector from the ECU and purple to the VSS (vehicle speed sensor).

Temporary mount point until I fab something up to sit in the center of the dash.

Here’s the final mounting, kinda ugly, but it works:

Thanks again to Yoshi and Dan!

NOTES: The speed part isn’t working because I have a mechanical VSS. I am unsure if this is completely because of the VSS or some other issue, but I have upgraded to an electronic VSS and it works like a charm. Get in touch with me if you want to hear more about this and possible solution for your personal vehicle.

This article will be technically geared towards the CRX and other Civic models from 1988-2000. However, the general implications of these changes are applicable to almost any make and model of car or truck. I will detail my own changes as well as cite a few cases of fellow members from my primary forum: ecomodder.com as well as give resources that will allow you to make your own decision on the matter. While I will be primarily discussing the transmission that will give you the best mileage, there are many forms your gearing can take to meet all of your goals.

First things first, what I did with my CRX. I began with an automatic and could barely squeeze 40 MPG out of it. Needless to say I was very frustrated with its performance. Not only did I hate the gas mileage, I hated the way it drove. So, I embarked on the mission to begin my auto to manual swap. That’s a whole other ordeal, which I will discuss in a dedicated article, but suffice it to say that when I weighed my options I chose the most fuel efficient transmission I could. I wanted the most bang for my buck, and I got it; I picked the transmission up for free from a www.honda-tech.com member. In the end I’ve averaged ~51 MPG over my last two tanks with the stick shift, and I’ve loved every minute of it.

On the technical side of things there are 5 basics transmissions found in 88-91 Honda Civics: the auto, the DX/LX, the Si, the HF, and the STD.

• The automatic is just that, automatic. It gets terrible mileage and doesn’t have much potential. If this is what you have a swap is highly suggested for greater gas mileage. Even with the most fuel economy-minded transmission the car will seem to have more power. If you can’t drive stick, learn; Hondas are very easy cars for new stick drivers.
• The DX/LX manual transmission is basically the middle of the road; it is basically the same as the Si transmission with a lower final drive ratio.

The Si transmission has the shortest gearing of an US civic transmission from this era. As far as fuel economy is concerned this transmission should be avoided, it will give you ~3,000 RPM at 65 MPH.

• I have the HF transmission in my car. It was built for fuel economy and it certainly delivers. The gearing is longer than any other car you’re ever likely to drive and delivers a healthy 1700 RPM at 55 MPH on the highway. Without this transmission I doubt I could so easily hit 50 MPG.
• The STD was the super economy Civic, and as such received a 4 speed manual transmission. This thing is just a step above an automatic and should be eliminated at all costs!

To compare on the technical side of things, here are the gear ratios from the four most used options you will have:

For those of us with newer Civics refer to the following tables (gears from these two tables are mixable but not final drives or complete transmissions):

For those of us with even newer Civics use this table:

With these go to this gear ratio calculator and take a look at cruising RPM and shift points that various transmissions will afford you.

There’s not much more I can do to arm you with information, so at this point I will give you some statistics from my own swap and some other information I’ve dug up over the ages. Here is what my gearing looks like across the board (you can see how high it is, my transmission top speed is something like 220 MPH): Now, you must be thinking that with such a transmission acceleration would be brutal, but this is not the case either! My shift points are as follows:

• 1 –> 2; 1500 RPM, 8 MPH
• 2 –> 3; 1500 RPM, 20 MPH
• 3 –> 4; 1250 RPM, 25 MPH
• 4 –> 5; 1250 RPM, 30 MPH

That leaves me in 5th gear accelerating from 30 MPH. Sure it’s slow, but the fuel economy is amazing, so I don’t mind. My lifetime automatic mileage was 35.8 MPG, and so far I have managed 51.2 MPG with the 5 speed CRX HF transmission; quite the difference, if I don’t say so myself (40%, beat that, acetone)! You can check out my online gaslog here at www.ecomodder.com.

Another forum member, named Darin (MetroMPG) swapped to a transmission with longer gearing and saw what he approximates as a 5-6% gain. This may not seem like much, but when you’re pumping out 75 MPG tanks and 117 MPG segments, it’s nothing to scoff at. You can check out his findings and process in his swap thread here.

I also helped another member upgrade from his 4 speed STD transmission to a 5 speed CRX HF transmission. Not only was the swap a lot of fun, but look at his gaslog. His driving isn’t exactly consistent and he doesn’t drive for great mileage, but the improvement is there. He’s gone from 38.8 MPG before the swap to 43.9 MPG after, an improvement of 13.2%. You can also see a correlation between engine off coasting and gas mileage, but that’s something for another article.

There will be more success stories to come! If you have any questions about parts, prices, or procedure feel free to email me and I’ll give you all the advice you need.

PS: If you’re wondering how to determine which transmission is which for EF Civics/CRXs, check out this picture:

Many people wish that there cars were a little closer to the ground. There are a lot of reasons for this; some people enjoy the look of a car that has been lowered, while others like the improved handling or reduced aerodynamic drag. For most people, all of these things are benefits, so naturally, there are lots of people out there with lowered cars. Now, it may seem like a daunting task, but it’s really not all the time consuming, expensive, or hard. Because this is a fuel economy oriented site let’s take a look at some of the theory behind the idea that a lowered car has less aerodynamic drag.

• V = wind velocity in tunnel
• S = frontal area of vehicle
• E = wheelbase
• Cx = coefficient of drag
• Cy = coefficient of drift
• Cz = coefficient of lift

Here you can see that drag is directly proportional to vehicle frontal area. When you lower the car you reduce the frontal area, and therefore the drag. Any drag benefit is specific to the vehicle but all should benefit (though it may end up being a very tiny amount).

Purpose: To intall adjustable coilovers that will let your change your ride height on a whim

Time: 4 hours

Tools:

-Strut spring compressors
-Jack and blocks (don’t trust a jack alone!)
-Basic socket set for general purposes.
-For my car I needed:
-Jack
-Blocks to sit the car on (don’t trust a jack alone!)
-19mm deep socket for lug nuts
-1/2″ drive
-3/8″ drive
-Torque wrench
-14mm socket
-Some extensions
-Two 17mm sockets
-14mm wrench
-Hex set (forget the size)
-Hammer
-Screwdriver or two
-Shop Manual

Warnings: Get an alignment when you change ride height or at least do the toe yourself! I will talk more about this later.

Use spring compressors! Don’t shoot the spring off the strut into a wall or some nonsense, many auto parts stores have free loaner spring compressors.

If you get the cheap springs like I did they will be bouncier than stock because of increased spring rate, and because of stock struts will be more likely to bottom out!

Before picture:

Front wheel well:

Rear wheel well:

1. Decide which wheel you’re gonna start with, loosen the lug nuts, jack the car up, and take that wheel off. Don’t forget to put bricks behind wheels to keep it from fidgeting. Also, sit the car on some blocks to keep it safely up in the air. Safety first.

2. I started with the front, so grab the front passenger wheel off and look at the stuff.

3. My first step was to take off the two 14mm bolts holding on the brake line you see above.
4. Then take out the 14mm bolt holding the bottom of the strut to the strut fork forgot to picture, but it’s right at the bottom of the strut and attaches it to a fork looking thing).
5. Take the 17mm bolt out holding the fork on. It’s a nut and bolt so I used my breaker bar to hold the nut while I undid the bolt. I had to use a hammer and screwdriver to get the bolt out, so do that and release the strut except for the stuff holding it on top. Then pull the fork part out completely so the bottom of the shock looks like this:


6. Get under the hood and undo the two 14mm nuts holding the shock up. There will be three, do the outer two, the middle holds the spring compressed. Hold onto the shock while you take the nuts off so it doesn’t fall straight to the ground. I forgot pictures of this but can take some later.

7. Now that the shock is down take your spring compressors and hook the little holder ends in there and connect with the rods. Try to have them on opposite sides. I had to smash the holders in with a hammer. As far out to the end of the springs as possible is good too. I know I pictured this but I lost it. Anyway, snug the bars down and begin to tighten the compressors a bit on each side, alternating. Mine used a 19mm head for the big rod. Compressor the spring evenly on both sides until it seperates from the ends on the strut where it is and use your hex key/14mm wrench combo to undo that middle nut on the top.
8. When it comes off take all the junk off and slide the spring off the shock. Keep track of all your washers and junk.
9. Undo the spring compressors the same way you put them on, turns out I had a broken spring:

10. Take the dust cover off your shock and reassemble everything like it was before but with the new coilover in place of the old spring. Put some little rubber washers that come with it down at the base of the shock to prevent rubbing and what not. Also, take the rubber thing out of the top hat and just sit the coilover in there without that thing in the way. Make sure during this reassembly not to leave stuff out like washers.
11. Slap everything together the way it came apart and look at your new shock junk, then stick it back in the way it came out and torque everything to spec.

12. Put the rim back on and whatnot and go about the other side on the front the same way as this.
13. With the front done, move onto the back. The back on my car is easier. you just need to unbolt to strut from the lower control arm and the lower control arm from the brake knuckle to move it out of the way.


14. So undo the 14mm on the strut/lca, then the 14 on the lca/knuckle.
15. Undo the two 14mms in the hatch (same deal as last time with the outside) and take the strut out.

16. Work the spring compressors again, and the same deal for dissassembly and reassembly of the coilover/strut.
17. Put it all back together again, toque to spec, and sit the car down.
18. Adjust the height like goodness so it’s level and what not and then you’re done with that part!

Here’s an after shot, pretty nice:

Everyone envies the person with the push button start. Perhaps it’s that cool cat with the S2000 or the fuel miser with the hybrid, but they envy is still there. With this write up I intend to show everyone how easy it is to add this to your own vehicle. This was done using CRX wiring, but with a simple check of wiring this can be duplicated for almost any vehicle. If you do this don’t forget to send me a picture of you setup!

Purpose: There’s the bling factor of having a push button start (especially if you use the s2000 “engine start” button, the anti-theft factor if you wish to hide the button, and the convenience factor of having the button near the shifter if you are using it during engine off coasting.

Time: 1 hour

Tools:
- Soldering Iron
- Wire Stripper/Crimper
- Screw Driver

Supplies:
- 1 SPDT (Single Pole Double Throw) Relay – 3.99 at my parts store
- Some female quick connect ends – 2.99 at the parts store
- Wire
- Solder
- The button!

Check out this schematic and look at your SPDT relay, pretty simple. Figure out which wires are which and wire the stuff up. I labeled this with the colors that are actually used in my CRX. This write up is applicable to almost any car, but you’ll need to figure out which wires are which if you want to do this to another car. Pretty simple. Most people use the S2000 start button, but you can use any button that is normally open and only connects when pressed.

And here’s a picture of the S2000 button, just for reference:

Wire the stuff in there not too prettily just to make sure it works. Here’s mine half done:

Another shot with indications and all that on it.

Get your button and figure out how to mount it. I am going the way of small button skirted by washer and then mounted in my cigarette lighter hole. Here’s the washer pre mounting and painting. I hot glued and burnt myself quite a bit, be careful.

I put this little cone over the button to paint the washer.

Painted shots, looks decent to me:


Wrap your crippled, burning hand in wet stuff:

Mount up the button itself into the center console part.

Finished the install with the new button, check it out:


Here’s a final shot having actually put the interior back in my car:

I’m very happy with it, piece of cake, as well.

Yet another blingtastic modification. It’s kind of fun to do though so I figured I’d throw it up here in case anyone cared to see it. There’s really no fuel economy reason for it, but whatever. The more you love your car the better mileage you’ll get, or at least that’s how I see it, *wink*

Time: 20 minutes

Tools:
- Hobby Knife
- Matches

Supplies:
- Crayon of your preferred color
- Shift knob
- Foam (for modeling)

My tools:

Here’s the shift knob when I got it in the mail, and little dirty:

I had to cut some hook crap off the bottom (which you prolly should do since that’s what to boot attaches to, but I wasn’t thinking and my boot it too short anyway, fool me):

Scraped the gunk out of the stuff I wanted to do on the top to get a better surface:

Melted up the loose ends on the bottom where I cut it:

Bunch of crap melted all over cuz it’s not an exact process. You need to shave the crayon and push the shavings into the ruts with your fingernails. I had the problem of when I heated it it jump out of the rut, but then I repressed-in the melted stuff and tried again and it worked. It took a few tries, but I eventually ended up with all the stuff in there and just had to clean stuff off. I had no problems over heating the knob with the matches, but be careful anyway:

Finished product:

Here’s the knob in the car, looking sorta red all subtle like (the light makes it so you can’t see it really but it’s there, and the knob is one of my favorites, go 90-93 accord!):

Here’s just a few of the more common fuel economy tips that I through together so that everyone would have a starting point for good fuel economy in reference to their car’s condition. These things won’t give you a huge boost or anything like that, but you need to start off with your car in good condition if you’re looking to go somewhere far in terms of fuel economy. So, at the very least, be mindful of these things and realize how they affect your fuel economy.

General Tune-Up Information – Whether or not you’re losing fuel economy to an overdue tune up is really a matter of guesswork, however, this doesn’t prevent you from doing the actual tune up. Once done, you will know that you’re getting the most you can out of such things. Besides, you really ought to get it done anyway.

Some common things to include in the tune up:

• Spark Plugs – I use NGK V-Power or Denso U-Grooves just because they are a reliable, copper stock replacement that’s cheap. Check out this page to learn how to read your old plugs to check in engine operation.
• Plug Wires – Use a digital multimeter to check resistance compared to what’s specified in your shop manual to see if you need to replace these.
• Distributor Cap and Rotor – These parts take the littlest, tiniest bit of wear with every spark. If they’re looking ridiculously worn down from the time a replacement might be in order.

Check Timing – Make sure your timing is within specifications with a timing light. Without proper tuning it is inadvisable to fiddle with your timing or leave the car out of time.

Motor Oil – A lighter weight motor oil will reduce internal engine friction. The Honda Insight, an excellent example of across the board fuel economy, uses 0w20 motor oil to keep friction down. Do this with caution, however, as lighter oils will increase oil leakage or consumption in more worn engines.

Grounds – Over the years your grounds get corroded and icky. Clean them up or replace them with some more blingtastic audio wiring to make sure they’re running at their peak.

Battery Terminals – Just clean them up with a wire brush, they get corroded and disgusting, no one like that.

Pump up the tires – This is perhaps the best thing you can do on this list. Most tires list the maximum pressure as 44 PSI, but members on www.ecomodder.com routinely step it up to 60 PSI. This may not give you a 20% increase in fuel economy, but you’re certain to gain a few percent out of reduced rolling resistance, and it doesn’t even cost anything!

If you’re interested in the safety of this change check out this police article that encourages over inflation for both safety and performance.

For more information on the fuel economy benefits of reduced rolling resistance and over inflation, check out this PDF.

Cleaning out the trunk – This is probably one of the smallest changes you’ll ever not see, but, for every ~100 pounds you haul around you’re costing yourself 1-2% of your fuel economy. So, if you’re carrying around a set of weights or something like that you just forgot about, get it out of there.

Take off that wing – Well, this isn’t exactly tune up material, but for as easy as it is to pop it off and plug the holes with some rubber grommets you might as well. Most wings are functionless, ugly things. Those that do have function increase downforce and therefore drag. While downforce may be a good thing at 100 MPH, how many fuel savers will be going that fast on a regular basis?