Hondaworkshop - project log
 

You can see my introduction here: http://forum.ecomodder.com/showthread.php?t=690&p=6888

In a nutshell: I have a 2000 Honda Civic DX hatchback automatic. It's stock except a factory front lip. I'm going to shoot for 40mpg.

In this thread I will track everything I do to modify the car and all the results I record.

Jan 26, 2008 - Removed Factory Mud Guards

These were an option I picked up that really do help keep the car clean, but as I've illustrated with the blue arrows, they are like 4 little pockets for creating drag.

http://hondaworkshop.com/images/mpg/mudflaps.jpg

Jan 26, 2008 - Moved front license plate down to block the grill

Its been rainy, so the car is filthy! In Texas, we're required to keep a front license plate to avoid harassment, so I decided to start by making the most of it.

http://hondaworkshop.com/images/mpg/licenceplate.jpg

You can see the two holes in the bumper where the top of the plate used to attach. Below that, from inside the grill, is a metal bracket that was originally affixed to the bottom of the plate. I did some creative bending to the bottom bracket so it would serve as a top bracket for the plate tucked inside the grill opening.

I also added a bit of 1/4" rubber tubing to the top edge of the plate just to keep it from scratching in to the bumper finish.

Future plans are to completely cover the top grill opening in a tasteful way.

This is good,
your car an my 04 Civic have similar designs.
I don't have any mud flaps to remove
but I like you idea for the license plate.
I've been toying with the idea of covering the lower grill
so the moved plate is a nice start that keep most of the stock look.

I think what you're doing is going to give me a good look into what I plan on doing to my Camry. I also have a '00 accord V6 but I'm lucky if I can get 20mpg with that so I mainly drive the Camry that gets between 20 and 25 mpg depending on conditions (I live in the city, lots of stop and go). I'll keep tabs on this thread to see what all you're doing to the civic to give me some ideas for my camry, good luck with your project. Just thought I would also pass this along, it's something I just bought for my Camry, you won't find them cheaper anywhere else, usually these cost $20/each but here they are just $18 for a full set (plus $15 shipping).

http://cripedistributing.com/stainle...ces-p-391.html

the only thing other then that you would need is you will have to trade your wheels for some standard steel wheels that can probably be purchased from Honda directly or from ebay or something. Also, if your car uses 15" wheels instead of 14" wheels like my car uses, that link I posted has some 15" covers for like $30 I think.

Feb 1, 2008 Update:

After doing the above two mods, using my old-fashioned way of calculating mileage (using the trip-odomoeter and dividing the gallons when I fill up) I have gained another 2-3 miles per gallon from removing the mudflaps and repositioning the license plate... to say the least, I'm hooked.

Just today my Scangauge arrived in the mail! Though its mainly cosmetic, I'll post pics of the install. This weekend I'm also going to look into starting a cover for the top grill opening. Stay tuned.

Definitely a nice job with moving the license plate, :)

Today the lower intake was covered using some foam pipe insulation
(someone else did it and is seemed simple to do)
and a bit of the top also using black duct tape.
Altho the commute home tonight is going to be a bad one
(freezing rain and snow) so I doubt I'll get any useful data on the ride home.
But between slowing down and doing a modified (for traffic) P&G I've got the mileage up from 32mpg in December, to average 37mpg in January.
My goal is 40 also.

Well, according to my Scangauge, I was able to easily attain 42mpg on my first commute with it. It took no time to figure out pulsing&gliding and coasting in to stops and driving sensibly up the parking garage all made a huge difference.

Can someone tell me why my mileage is so much higher than I ever expected? Maybe me tire height or my Scangauge settings? Maybe I should push for 45mpg??

On this morning's commute I pushed it up to 44.5mpg!!!

Now I'm beginning to think I am gaming the scangauge by pulse-gliding. Am I really able to do that well or am I tricking the device?

Until you calibrate the gallons in the tank at Fillup,
the mileage will be off.
I had to readjust mine and suddenly I was getting 45mpg,
at the next fillup I had to readjust the amount delivered back down
and the mileage went back to normal.
There is a very specific method for calibrating the tank
and I guess it HAS to be done right.

Guess I need to read the manual. :o

Good information to know, I didn't know it needed special calibration. I'll make sure I RTFM when I get mine.

February 17, 2008

The Scangauge is now more calibrated, and showing roughly 30mpg for mixed traffic (gridlock/highway) and 38mpg when its only highway. Driving habits, license blocking the grille, and removal of mudflaps help me get there.

Today I was in the garage building another air blockoff for the front:

http://www.hondaworkshop.com/images/...vic_block1.jpg

http://www.hondaworkshop.com/images/...vic_block2.jpg

I started with cardboard to build the general model, then built the final one with corrugated plastic. It was covered with some old silver vinyl that I happened to have laying around, and then attached with zip ties.

I cant wait to try it out Tuesday. :)

Nice work! That block looks great on the car. How about those small inlets on each side of the main, lower grille? Are they actually holes through the bumper? If so, I'd do them as well.

Congrats on the progress so far. What else do you have in mind?

If this one makes an improvement, I want to do something more permanent and flush. There is PVC sheeting at Home Depot, and I could remove that grill section and 'wrap' it.

One of the openings is blocked, the other one is opened. Should I try to make them flush with the bumper or just block off the open one?

The other plan I have is to make a underbody cover for a large void near the rear bumper...its like a parachute back there.

Closed is better than open, and flush is probably slightly better than simply blocked. But we're splitting hairs here. Don't lose any sleep over making it flush, if simply blocking it is easier.

Sounds like a plan with the rear undertray. Looking forward to watching your progress.

You should do a fuel log as well - have you been tracking your fuel economy at fill-up time?

I have, but I had to interrupt my typical cycle to get the scangauge calibrated. Now that its on, I'll be able to do it using the same pump at the same station every time.

Looks pretty good. Keep it up!

February 27, 2008 Update:

I busted my OEM front spoiler in two on a parking berm... now I have the choice of either paying $100 for a new one that could break again, or fabbing something up that is more FE specific. I'm wondering, should I make a small front air dam or make an undertray?

^^ Repair it with fiberglass on the inside.... To fill the crack on the front, apply tape over it (to conform to shape), then fill with resin (polyester won't yellow in the sun which may be a good attribute for you). Then wet sand with super high grit so it appears clear.

That is, if you want to repair it.

I think that a front air dam without side skirts will not be as effective as a smooth full size undertray with wheel fairings.

With an air dam and side skirts, you don't have to care about how rough the underside of your car is, plus it's probably easier to build and install, but it can increase your frontal area by a good 10% and frankly does not really look good compared to a stealthy undertray.

I've done some glassing before, but this thing shattered into too many little bits. :(

I'm going to try out the undertray with wheel fairings.... but first I'm doing a warm air intake.

Thanks for the input!

Looking good. Did you match the paint?

I've got the same front bumper with the giant gaping hole in the bottom. I'm thinking of covering the whole mess and keeping the top one open for engine cooling. I don't have the two on the sides or the spoiler that you broke. Maybe delete it (less A) and start on the undertray...spend the 100 on materials :D

And those don't look like DX wheels ;)

I think basjoos has pointed out in another thread that you're better off (for best aero) blocking the upper opening and leaving the bottom one partially open, rather than vice versa. If aesthetics and SWMBO permits.

Interesting, but the 5th gen civ that basjoos and others have don't really have much of an upper opening. Which was his point, now that I found the statement (on GS)

I haven't found Cd figures for each model of Civic, but the 5G is apparently .31-.33 and the 6G is ~.36. So I have more work to do :(

My problem is that I have to sit at too many stoplights and I live in a hot climate, where it's 90F from April to October, AC is a necessity, and cooling is the issue. My thinking is that the upper opening is more beneficial to cooling, and smaller, so it would be the one to keep in this case. I'm thinking of an AndrewJ style airdam and leaving the upper grill as is. Next week when I start getting daylight after w*rk I'll look at the radiator/airflow setup more closely.

My 92 Accord was a chronic overheater, the radiator leaked, then a hose blew, then the water pump leaked, and one of the radiator fans never worked. I had to turn the AC on to get the condenser fan to cool the engine in traffic. :eek:

I think my first mod will be a killswitch (thinking EFI as it's the fuel we're trying not to use) anyway, but as this is a similar car in a similar climate I'm following this one with particular interest.

We get that kind of heat humidity in Ontario in the very peak of summer - though not for the length of time you have it. I've never had a car with A/C, though sometimes I've wished for it.

I'd suggest you can extend your non-A/C season with one of these:

http://tbn0.google.com/images?q=tbn:...adedseat_1.jpg

Wooden bead seat cover. I call it "my A/C", and I only put it on for about a month or so per year, but having a bit of air circulating behind & under you makes a world of difference. I swear by mine.

Just did a fillup today, and its looking like I might be about to reach my goal of 40mpg average on this new tank... Why?

• First: warmer ambient temperatures
• Second: the addition of a Warm Air Intake setup that showed an immediate spike in my mpg numbers. Are you listening, fellow Honda folks?

I'll get some pics of my warm air setup ASAP.

My intake temps have gone from basically ambient before the WAI mod up to an avg of 140°F, sometimes peaking near 200°F. The only question I have is "what could be the negative side effects of the WAI, and how can I address them?".

I know the horsepower is compromised, but honestly I have not put the gas pedal down past 1/4 since I got the scangauge, so I wouldnt really notice. What I'm thinking is premature wear on spark plugs? Should I buy colder plugs or adjust my timing next?

BTW, I'm going for a wood-bead seat cover soon, too. Here in the middle of Texas, AC is a serious necessity for much of the year.

Duly noted.

Looks like something I may have to tackle tomorrow. I've been thinking about an easy way to do it for a while now.

In Cali one cannot technically alter any part of the intake (or exhaust) system without the modifying part having the CARB stamp of approval.

Fortunately before the air filter, the intake is split, half coming from under the wheel well. The other comes from the engine bay.

Our peak of summer is a month or so of 85F low temps. I never had AC either until I moved here. It's a wet heat!

Interested in how you did the WAI
 

What did you do for the WAI? I would love to try that mod on my Honda. Did you do it yourself?

March 22, 2008 - Added a Warm Air Intake

I wanted to wait until I was happy with this WAI before posting pics etc. so this is a belated post. Let's get straight to the pics:

http://www.hondaworkshop.com/images/mpg/wai_overall.jpg

The inlet is a $5.29 flexible steel exhaust tube from an auto-parts store. Its is approx 2-1/4 in diameter. I tucked it just under the exhaust manifold shroud, but I was careful to make sure it was not actually touching anything. It is zip tied firmly onto one of the fan shrouds. I also slightly rearranged the O2 sensor wire so it was not touching the inlet.

http://www.hondaworkshop.com/images/mpg/wai_inlet.jpg

The coupling is a 2" plumbing coupler from Home Depot. This costs around $2.99. Be sure to get one that is safe to use with hot water, so it will withstand higher temps.

http://www.hondaworkshop.com/images/...i_coupling.jpg

The filter box for my particular engine (D16Y7) is uncommon for Hondas. The filter is inside a box with a downward facing throttle body... kinda like a carb intake that was converted to fuel-injected. I have asked around, and it has been agreed this was designed for fuel efficiency, better emissions, and low end torque improvement. In any case, this particular manifold is well-suited for conversion to a WAI. I simply sawed it off short, removed the sound-dampennig box, and put my flexible inlet on.

http://www.hondaworkshop.com/images/mpg/wai_filter.jpg

This mod has been the biggest improvement I've seen outside of changing my driving habits. I'd say its around a 10% FE improvement, and with my driving style changed, I haven't noticed the accompanying loss in horsepower at all.

With intake air temps averaging 140°F I'm still wondering what this will do to my spark plugs and sensors. I'm also getting an itch to pre-warm my fuel...any thoughts?

Looks Good!
 

I blocked off some cold air entry points thereby raising the IATs accross the board. With a slight change in weather (Temps up 8-10° and RH down to 25-40%) and this mod, it looks like I have about 5% savings on same weekly trip cycle. Judged by ScanGuage and Fill Data, both in perfect agreement.

My IATs are nowhere near 140° however. Maybe consider backing the IATs off by moving your intake a few inches back of the manifold at a time.

I'd think on startup/early ops, the 140° may be very beneficial, but as FWT get normalized around 185°, I'd say a few degrees less WAI will still provide same FE increases.

I found a spot in my parking garage, that if I back in to, the sun will only shine on my hood for about 2-3 hours prior to the afternoon drive home. I'm anxious to see if the additional underhood heat load will help on getting the FWT and IAT up earlier on the trip home.

Well, it turns out my gauge got wonky somehow, so I only got about 37mpg on the last tank... still good, but not the 40 I was hoping for.

I'm going to take your advice and try to pull the tube away from the manifold to get somewhere around 110°F on average. Stay tuned. :)

You know you can adjust the SG to correct for differences at fill time.

Yeah, I've been doing that and getting some wild swings in useage readings vs. fillup readings. I'm using the same pump at the same station, but I think maybe the variations in temps threw it off a bit, because I did a morning fillup once then an afternoon fillup later on, and the temps were different by maybe 40°F.

I dont know what else it could be, but when I fillup, I'm adjusting my useage by more than a half gallon every time. Maybe I should try using a different station/pump, or not worry about it now that temps are more consistent.

I've just kept a running log of Scangauge gallons (uncorrected) vs real gallons. After a year, it's pretty consistent, so I just use the average offset now. That's +8% fuel in my case.

Mine seems to start making FE progress at around 90°, and seem to be really good at 105°-110°. I think you'll see a difference. I added another baffle over the weekend, and my return trip averaged ~ 105° IAT today, previously 95°ish.

I went to synthetic oil this weekend. The previous owner (first 36K) used dino oil from bulk drum at dealer. The FWT was 5-8° cooler than similar trip conditions last week. Result - return trip was 46.8mpg (up 3mpg) after those two mods. Daily trip average was busted by an errand I had to run this AM at 8:30 down the busiest road we have. Even with that diversion, I was up 0.7mpg for the day.

My ScanGuiage adjustment stays at -1.6% the last three fills. Dead on.

Today I commuted with the intake about 4 inches away from the exhaust manifold. AVG temps were 125° and FE increased by a little bit. I'm going to try to get to 105° tomorrow. Thanks everyone for the tips.

I realize this is a Honda inspired thread, but I've noticed similar results on my Dodge RAM. When the OAT is about 90*, I see a slight mpg improvement driving back from work. I have tried a WAI from the eng bay side of the radiator to the airbox, but that only gave a 5-7* temp rise. Not enough when it's 30*F outside.
This makes me think I need to remove the insulation I wrapped around my manifolds. I don't think I gain anything from it, other than slightly cooler eng bay temps...might have to start a thread like this one to catalog the journey.

I highly recommend synthetic oils. My truck has seen synthetic since its 1,500 mile mark. If you like to worry (like I do), you can get a filter-mag for your oil filter. It's a curved magnet that sticks to the filter. It traps all the ferrous stuff inside. Remove and stick on the new filter at your oil change....