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:

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?

Replacing the thermostat is one of the easiest, cheapest, and most imperceptible ways to increase fuel economy. Stock thermostats, which generally open at around 180 degrees, are a compromise between performance and fuel economy. If you’re treating your engine kindly you can get away with installing a 195 degree thermostat in order to push your fuel economy up ever so slightly. Since most radiator fans will not turn on until a 210+ degree condition is reached, you should be fine under normal conditions.

Take a look at this graph relating fuel trim to engine temperature in Hondas. This offers some theoretical evidence of the savings, though it is generally so small that testing would be nearly impossible:

Purpose: A hotter engine runs more efficiently. By increasing the coolant temperature a few degrees we can improve the efficiency of the engine very slightly.

Time: 30 minutes

Tools:
- Socket Wrench
- Basic Metric Socket Set
- Pliers

Supplies:
- 195 Degree Thermostat
- Thermostat Gasket
- Coolant to replace that which you spilled

1. Take a look at your damn engine compartment. Find the thermostat housing. It’s in the middle of this picture, with the big hose going to it:

2. Get your pliers on the big clamp, move it off, and take off the big hose going to the thermostat:

3. Take the one side of the housing off (two 10mm bolts) and expose the thermostat.

4. Yank the old thermostat out with some pliers. Now you realize where all the spilled coolant will come from!

5. Put the gasket or new gasket on the new thermostat.

6. Put the thermostat back in and replace the housing. Tighten it down not to much, but just enough. Torque specs help!:

7. Look at your completed work.

Have you ever hated the look of your radio antenna? Or maybe been bothered by all the aerodynamic drag? I have. Solution: It’s gone!

Purpose: To cut down on aerodynamic drag and improve the look of the car.

Time: 15 minutes

Tools:
- Flathead Screwdriver

Supplies:
- Block Off Plate
- Gasket
- Reused Screws

You can get this stuff at the local dealership or online (cheaper) at one of these places.

Here’s the antenna. Undo the two screws and yank it out. Make sure to unplug the other end from the stereo.

Awful picture of the antenna on the ground:

The left over hole:

The two parts, I spent about 10 bucks on both:

Put them on with the old screws:

Admire your work:

The CRX no longer looks like an RC car! Quick and easy (mehbe not too important) but it was certainly worth it to me.

The front grill block is on of the quickest, easiest, and cheapest ways to cut down on aerodynamic drag in your vehicle. While it doesn’t amount to much, it does make a difference, especially considering that a large amount of aerodynamic drag is caused by this opening. It’s best to leave it only partially blocked so that the radiator recieves some airflow, however, a large block is okay because radiators are typically larger than they need to be, and fuel economy drivers tend not to abuse their engines too heavily.

Many new cars, including certain Mercedes and Hondas use electronically controlled radiator shields that open/close depends on engine cooling requirements. Take a look at this Civic for an idea what this looks like:

Purpose: To prevent air from entering the grill to reduce drag as it moves through the radiator and engine bay.

Time: 1-3 hours depending on complexity of project

Tools:
- Hobby Knife
- Hot Glue Gun

Supplies:
- Coroplast
- Spray Paint
- Foam (for modeling)

I chose to repaint the trim on my bumper as well as do the grill block at the same time, so first I removed the bumper. If you leave it on you can get it done much more quickly, but that’s up to you. Just follow my mounting instructions with the bumper on the car.
Click here to see how to remove your bumper (as shown in the wire tuck page).
This is my bumper removed, you can see the grill opening as well as the two pockets on the side. The side pockets are not supposed to cause much drag but I covered them anyway just to smooth thing out as much as possible:

Here’s another shot to get an idea of the bumper’s geography:
I used this style of insulation foam to make templates because it is easy to work with:
One of the templates sitting in a side pocket:
I then transfered the template to the coroplast, cut some support to place down the side of the pocket to mount the coroplast to, and cut off part of the coroplast towards the center of the bumper so it would mount flush to the bumper where it tapers together:
The center pieces are just glued to the ribbing on the grill and then glued around the edges from behind:
I taped up all the painted portions of the bumper so I could respray the trim and the coroplast black:
A shot of the finished product remounted:

I think it turned out pretty darn good,