05' Ford Focus ZX3 Hatchback Aeromods
 

I havent done much yet but i have seen an improvement in mileage since purchasing a scan gauge and being mindful of my instant fuel consumption. Now more recently i have added some light aeromods to the car and increased fuel economy from 33-34 before the scan gauge to 39 and change after the grill guard and gauge. the commute consists of essentially 15 miles medium city driving and 30 miles of rural highway driving.

Im not saying the grill guard was responsible for the majority of this, i have certainly adjusted my driving style as well as reduced my highway speeds in an effort to save fuel on each trip. but with the addition of the grill i have certainly seen an increase in mileage at the pump.

Since everyone loves pictures here's the vehicle with first grille guard in temporary form (got some weird looks and a lot of questions at work).
http://i53.tinypic.com/16jiteo.jpg

Notice the lower partial block is only on one side, originally i had them symmetrical on both left and right. however on my first test run (across the state) i noticed intake and water temps exceeding what i was comfortable with. AIT was reaching 130 before the electric fans would cool the engine bay. So i removed the driver side block which was inline with my air intake, at stop lights on hot days my temps still get into the 120's but will drop quickly at green. I am considering adding more lower blockage in winter.

To this: As you can tell I painted coroplast and secured it with fishing line and some clear tape on the lower grill.

http://i54.tinypic.com/whfql0.jpg

from another angle

http://i55.tinypic.com/qq8jk8.jpg


Needless to say my girlfriend approves of the new look in comparison to the blue tape before lol

Nice works on the grill mod.

You seems to do a good job at driving it since I've never done any better than 32 on my 06.

I like the clean look of the grill block. With the good fit around the blue oval, it just kind of fades out of sight unless you look for it. Good work!

If you are anything like me, the biggest economy improvement was adjusting the nut behind the wheel. :D

Ha, yes and no.

The motivation for purchasing the vehicle was the low mileage in my truck combined with a 90 mile roundtrip commute. when i first got the car i was rough on it in town but tried to keep it under 70 on the hwy which yielded the 34mpg's avg before finding this site. 34 vs 15 made m happy at the time, certainly the driving habits has made a large difference but not as much as one would think.

Got the 03 version of the ZX3 and best I've seen this summer is 36 mpg avg...now down to 34 or so. Mine is a California model and I'd guess the fuel mix is more controlled by the rear O2 in order to provide a complete burn in the cat...or so I've heard.

Also mine is an auto.

Will be testing the Volo chip soon.

Here is a pic of a new mod I just finished:

http://www.nonags.org/members/nijqk/ZX3frontpan2.jpg

Made of 3/8" sheathing plywood...edges were painted with fiberglass resin and 2 coats of oil based paint put on. Made the mistake of not paying attention to warping...after the sheet is off the stack...they warp. If I had made it so that it warped DOWN...I wouldn't have needed the stiffeners. Drilled 2 holes in the xmember to hold it at back...2 more will be in the plastic lip at front...4 in all. The hole in the middle is for the cat and exhaust...they don't sit down in the hole...just there to keep the heat away from the wood.

I THINK this will be more effective than the lawn edging I had on the front...not to mention that it would never handle the snow. At the back it is at the same height as the lawn edging was. I figure a gradual redirection of the air is better than a blunt forcing of it to the sides.

Cool ! Any idea on its weight ?

Thats pretty sweet, i crawled under my focus the other day to see how feasible a belly pan was and noticed except for the rear its not "too bad" under the car. I still want to really smooth it out but the rear would probably benefit the most.

Under the front on mine(style is a little different on the 05?)...the OEM dam is about 5" above the general undercarriage. This area under the engine and trans allows air to directly hit the oil pan and trans pan and assorted "stuff"...likely causing a lot of turbulence to the rear. Once past the engine...things look pretty smooth...except right at the back near the bumper....but the bumper is above the rest of the undercarriage...so it shouldn't catch air much. *After looking at it again...guess things are pretty sloppy in front of the rear axle too.

Might install some kind of deflector in front of the tires on both sides....thinking of angling them so the air is routed out to the sides.

As far as weight...it isn't real light....maybe 15 lbs or so. But unlike plastic it won't deform with heat....and is strong enough to handle snow...etc. 1/4" plywood might work OK...but it's hard to find it with outdoor type glue.

I'm going to close off the upper opening in the front like you did...and maybe some of the lower area temporarily during the winter.

Actually installed it...no issues on a 65F day with the wood getting too hot near the cat and exhaust. It does decrease the ground clearance by maybe 1/2" or so at the back.

http://www.nonags.org/members/nijqk/ZX3frontpan3.jpg

looks really nice, how did you mount it?

At the back you can see the 2 5/16" 18 bolts...the xmember was drilled and tapped for these. The front sits on the air dam lip...but also has two screws holding it just in case.

I used some old paneling to make a pattern. Cardboard was used to shape the wheel well areas...mostly following the plastic liners. Once the back was shaped...I just bolted it up and then traced a line around the front dam...cut it there. Had to trim the bottom of the plastic serpentine belt shield also.

The stiffeners should have been placed a little farther to the front....or even better...should have used the other side and had it warp DOWN. Due to the shape of the lip...the plywood won't sit perfectly on the lip.

The 1/8" paneling fit much better...but the indoor glue would have delaminated fairly quick?

good call on drill and tapping some parts, sadly i hadnt considered that on mine. I recently purchased a tap and die set, might have to use it soon!

I went ahead and added back on the drivers side lower air dam and put a small 2"x1" hole in it to allow some flow to the air filter and have seen more consistent air intake temperatures not exceeding 90' while cruising and a bump in engine temps back around 200. since most of my typical commute is cruising i dont think i will strees the electric fans at stoplights that often. I also was recommended a new route to work that involves more low speed driving at less then a mile difference with considerably less traffic and lights.

The past two tanks since changing the large white air dam havent been as impressive to me as the initial two tanks. i think the new block allows too much air to get trapped and still pass thru the upper grille. I think there will be some lexan in my future.

I am about to undertake some changes on my 2011 Focus 4 dr. I have been working on my driving style. I average 31mpg and up to 47 mpg on hwy. The sweet spot seems to be 60-65 mph on the hwy.
Putting eco tires on as soon as they get here. Cut sheet metal for under body seal all looks good only open area near front. Adding vortex generators to brake up air. I hope to get at a consistent 45+ on hwy. Hope to add instant mpg gauge next month.

47 instantaneous on the highway at 60-65? thats very impressive for a stock vehicle

What did you use for material for the upper grill guard? It looks really good. I'm looking to do the same to my 07 - but want something very lightweight. Thanks!

Front block
 

I have not done mine yet. However I plan to use sheet aluminum.

I think a front pan gained around 10% in mpg for a Prius?

Tested a lawn edge Air dam 2 weeks ago and saw no appreciable gain and possible loss of mpg's at cruise. pics below of lawn edging.

http://i40.tinypic.com/11av050.jpg

http://i39.tinypic.com/10cjm0y.jpg


the air dam has been cut to act as a deflector for both the front tires.

Also if you look close on the first pic you will see i taped the holes in my steelies, there was no gain noticed, however my wheels/caps stay clean much longer than they used to :)

this week im experimenting with the rear of the vehicle, i will try and post some updates when i get a chance.

question
 

What did you use to cover the fog lamps? it looks great - can't even tell what is behind the covers - thanks!

thin ABS plastic bent to shape and siliconed to the car, i know silicone isnt the best answer for most people, but i decided it was ok to me for this car.:thumbup:

did you heat the plastic and then from the coutour and let is cool to hold it's shape? of is it so thin that the silicone holds it in place? did you start with black or did you paint it? sorry about all the questions - but this is exactly what I'm trying to do to my 07 ZX3 - Thanks

the plastic is very thin, i cut out a thick paper mockup to the desired shape. then trimmed the plastic out from the paper template. i then took a lighter and slowly began bending the plastic to the desired shape, i would heat and bend some then hold up to the car. heat and bend some more and hold up to the car. eventually it was near perfect form, at that point i roughed up the abs where the silicone would adhere and laid a bead of silicone on the car where it would need to touch the plastic. i placed the plastic over the silicone and used painters tape to hold it over night to allow the silicone to firm up.

Great - Thanks - I love this site - lots of good ideas - I'm actually working on a mod now that would (if it works) result in well over 100 mpg to my 07 Focus (highway only) - without changing anything on the existing design by Ford - just adding a mod - if it works I hope to sell it and retire - either to an oil company (who might never use it) or to Ford to see if they might want to incorporate it into their line of vehicles.....so anyway - thanks for your help on the abs - hope to add it to the vehicle soon.

ok...so here is my latest idea...

http://i43.tinypic.com/3444abb.jpg

my only issue is fords want to be spoiler thats part of the hatch body panel.
any thoughts as to how beneficial this would be if i were to seal the cabin up with the hatch lid open as seen here?

Since the hatchback's integrated spoiler sits higher in the airflow when the hatch is partially open, you'll end up with a larger trailing wake, even if you were able to smoothly seal the other gaps.

I think i could remove the sheet metal that forms the spoiler and make a custom fiberglass or sheet metal smooth panel. then i would gain about 2 feet of vehicle length that improves the profile. I just wonder how much it would be worth investing in doing so...

It would probably be easier to keep the hatch closed to keep the weather out and make a kammback instead.

questions on the ZX3....???
 

* has anyone done TUFT TESTING on the rear of the ZX3? I have a set of AIRTABS I bought cheap off of Ebay...was wanting to mount them on the sides in back...and want to know what the typical flow directions are at various points along the sides...since with previous vortex generator testing I found that not all air flows are going directly to the rear at the back.

* has anyone testing using AC vs windows down in hot weather with this car?

airdam/mpg
 

FIAT's aerodynamics folks conducted wind tunnel studies and determined that on a car with a particularly well executed underside,that a front air dam could actually increase the drag.
This sort of thing is going to vary from one car to another.

I'm giving up on the Airtabs...seems they are not likely to work on a car? Might make my own VGs that would have less wind resistance and possibly some mpg benefit.

* Has anyone tested AC vs windows down?

* Has anyone tested these?

AutoVentshade IN-CHANNEL SIDE WINDOW DEFLECTORS - JCWhitney

My experience with the ZX3 in warm weather is that without AC...you'd want about all the air coming in the windows you could get to make it habitable.

The wind deflectors keep most air OUT of the car ...though with the windows cracked you might see more flow into the vents?

Might be possible to trim...say the lower end of the wind deflector to allow some air flow into the car with the windows all the way down?

typically the AC will knock down my mpg's from upper 30s to 40 down to low 30's average. as far as comparison between on vs windows down, its close to the same if i cycle the AC at lights and keep it on recirc while cruising and bump the air on and off depending on how warm it gets in the car.

if im doing sustained driving above 45 i will just give up and turn the air on.