The aero mods begin (Now working on Diffuser) !!!

[Recumpence]

Hello All,

 

I have begun doing some areo mods on my Max. Today I made clear wheel covers. I made them out of 1/4 inch thick Lexan (Polycarbonate) plastic. I do not like the look of solid wheel covers. Heck, the cool stock wheels on the C-Max are just too nice to cover up. So, to that end, I decided to make clear covers. As you can see by the picture, they are pretty much invisible (other than the valve stem hole).

 

These wheel covers are fastened to the wheels with five 1/4-20 stainless button head bolts. I drilled and tapped shallow holes in each wheel for this. I would not recommend this as it is easy to break a tap or in some other way screw up a tapped hole and the OEM rims are not cheap. However, I have a small machineshop and a HUGE amount of experience in fabrication. So, for me, it was a snap. Also, as for wheel strength, these are 15 spoke wheels. I only drilled into ever thirs spoke. Also, the spokes are a good inch thick. I only drilled and tapped about 1/2 inch deep into the spokes. Trust me, there are NO strength issues, what-so-ever. I never plan on selling my car. So, I have no concern about a perspective buyer complaining about the holes. Actually, if I remove the wheel covers, I just have to insert the bolts into the holes and the small shiny button heads look like a visual accent anyway.   :)

 

I have about 3 and 1/2 hours in this project and one piece of plastic. So, the time and cost investment is not large.

 

I chose 1/4 inch thick for a few reasons.

 

#1 It was easy to obtain.

 

#2 The rims are a tiny bot more than 1/4 inch narrower than the tire edge. So, the 1/4 inch thick wheel covers almost perfect fill the void making a nearly perfectly straight transition for the air flow from the tire edge to the disc and back to the rear of the tire edge. It is more earodynamic this way.

 

#3 I felt that plastic would not be rigid if it were any thinner.

 

I have driven it a tiny bit. But, not enough to give a decent report on mileage improvement. In fact, I think it will take a few hundre miles to really get some decent numbers to share. I can tell you that most people who use covers (On other cars, I have not seen any on a C-MAx yet) report somewhere around 1.5 to 2mpg improvement on the highway. I assume about half of that improvement in town. My driving is 70% in town and 30% on the highway. So, I will not see the large improvement that is possible. But, anything helps. Also, I get annoyed when I get on the expressway and watch my phenominal in-town mileage drop. So, this will help.

 

Beyond this, I plan on making some very nice new flat grilles, complete the lower pan under the rear of the car, and add a lower chin spoiler to reduce the volume of air compressed under the car.

 

Anyway, I will let you know how it goes when I do more driving.

 

Matt

Edited December 21, 2013 by Recumpence

[joe]

I would be concerned about heat build up.  There are two reasons why the wheels have all that open space.  Save weight, and allow heat to escape - both from the brakes and the wheel bearings.

[Recumpence]

I hope this doesn't come across as rude, but apparently you do not understand hybrids. Nearly all braking action is accompished by way of brake regeneration. That happens in the electric motor, not the brakes. I have 22,000 miles on my car and I have never cleaned the rims. There is no brake dust there. I have reached through the wheels and touched the brakes after stopping without any noticeable heat. The brakes only heat up if you panic stop. Then they cool down very quickly. The vast majority of hybrid braking does not build up any heat at all.

 

The wheel bearings are only affected if you trap brake heat. The bearings themselves do not heat up enough to make any difference.

 

Also, there is airflow behind the wheels. This is not an air tight arrangement. It only cuts down on outside turbulence around the sides of the car.

 

Matt

Edited May 25, 2013 by Recumpence

[fotomoto]

The Honda Civic Hybrid has used nearly solid wheels for many years.   Bolting on a used set of those has been an eco-mod for the non-hybrid civic owners looking for easy mpg's.  

[StoBro2]

I hope you remembered to use anti-seize compound on those stainless steel bolts in the aluminum wheels!

 

You will probably find that the polycarbonate will start to yellow rather quickly upon exposure to UV light from the sun. The headlamp lenses are especially coated/treated to slow down UV degradation, standard sheet stock Lexan rarely is unless it's an architectural glazing grade.

[Recumpence]

Ahh, the yellowing is something I had not considered. I have used Lexan in vehicle applications and never noticed it. That being said, I do not think I have ever used it in continuous outdoor exposure.

 

I will have to keep an eye on that.

 

I thread stainless bolts into aluminum for my bicycle drive systems all the time and have never had an issue. I know stainless galls in stainless, and aluminum galls in aluminum, but I have never seem them gall together. Of course, just because I have never seen it, does not mean it cannot happen.........    ;)

 

Matt

[plus 3 golfer]

Pic look great. You could get clear uv film and put over the Lexan. It should also prevent the Lexan from scratching and likely be easier to clean.

Edited May 26, 2013 by Plus 3 Golfer

[Recumpence]

Wow, what a wonderful idea!

 

Thank you. :)

 

Matt

[Recumpence]

I just removed the passenger side mirror to test what my mileage improvement is. Most guys say roughly 1mpg on the highway per mirror. This thing is freaking HUGE!

 

Oh, it only took 15 minutes to remove the mirror and replace it wil a thin piece of carbon fiber.   :)

 

If I do not see an imrovement in FE, I will put it back on. No biggie. If I see a good improvement in FE, I may replace the driver's side mirror with either a fisheye camera or a possibly a tiny mirror (to satisfy the law) along with a good quality fisheye camera. Actually, I could do camera on each side and have plenty of visibility without the aerodynamic loss.

 

I love that this is so easy to do and reinstall if desired.

 

Matt

[C-MaxSea]

Matt,

 

Any update comments on your mods & MPGs?  I would love to see a close-up on your Lexan wheel covers.  Did you do the front grilles & spoiler?  Driving light covers.................

 

Nick

Edited October 7, 2013 by C-MaxSea

[Phil1336]

I just removed the passenger side mirror to test what my mileage improvement is. Most guys say roughly 1mpg on the highway per mirror. This thing is freaking HUGE!

 

Oh, it only took 15 minutes to remove the mirror and replace it wil a thin piece of carbon fiber.   :)

 

If I do not see an imrovement in FE, I will put it back on. No biggie. If I see a good improvement in FE, I may replace the driver's side mirror with either a fisheye camera or a possibly a tiny mirror (to satisfy the law) along with a good quality fisheye camera. Actually, I could do camera on each side and have plenty of visibility without the aerodynamic loss.

 

I love that this is so easy to do and reinstall if desired.

 

Matt

I`m amused by your (an*l) obsession of scientifically attempting to derive every possible extra MPG out of your C-MAX.  I for one am content and very satisfied if I can obtain Fuel Economy anywhere in the high 30`s for City and low 40`s for Highway.  Considering its a comfortable decent size Vehicle and not a tiny "Flintstone Car", I was thrilled with my 11` Fiesta that got consistent 33-35 mpg City and 41-43 mpg Highway.  If the C-MAX averages close to 40 mpg on average, whats the complaining about?  Best of luck with your experiments but I for one will keep my C-MAX just as it is, both Wheels (uncovered )and utilizing (both) exterior Mirrors.

 

 

Reason for Mod update: edited to make this post "G" rated.

Edited October 8, 2013 by Jus-A-CMax

[C-MaxSea]

Well, I understand your amusement Phil, it is certainly that & more I'm sure (like reducing exhaust emissions). Let's just chock it up to "to each his own".  I could never imagine touching the mirrors, but if I had a machine shop ..............  I'm more than happy, rather thrilled with 45 - 48 MPG with no mods.  As long as we can laugh at ourselves, it's all good.  Take care,  Nick  

Edited October 7, 2013 by C-MaxSea

[wab]

I just removed the passenger side mirror to test what my mileage improvement is. Most guys say roughly 1mpg on the highway per mirror. This thing is freaking HUGE!

 

Oh, it only took 15 minutes to remove the mirror and replace it wil a thin piece of carbon fiber.   :)

 

If I do not see an imrovement in FE, I will put it back on. No biggie. If I see a good improvement in FE, I may replace the driver's side mirror with either a fisheye camera or a possibly a tiny mirror (to satisfy the law) along with a good quality fisheye camera. Actually, I could do camera on each side and have plenty of visibility without the aerodynamic loss.

 

I love that this is so easy to do and reinstall if desired.

 

Matt

 

Some day we won't have mirrors.

Tesla, Ferrari, Lamborghini, Toyota, etc are almost ready now

 

http://www.teslamotors.com/modelx

 

http://www.lexus.com/concept/comingsoon/index.html

 

Our motor home has mirrors and cameras but only 1 display.

 

When I turn on the turn signal the display shows that side. Most of the time it's just as good as looking at the mirror.

 

I've thought about adding displays and removing the mirrors.

[Jus-A-CMax]

Well, I understand your amusement Phil, it is certainly that & more I'm sure (like reducing exhaust emissions). Let's just chock it up to "to each his own".  I could never imagine touching the mirrors, but if I had a machine shop ..............  I'm more than happy, rather thrilled with 45 - 48 MPG with no mods.  As long as we can laugh at ourselves, it's all good.  Take care,  Nick  

 

Neither could I. However, these mirrors are like air brakes. The faster we go, the more "breaking effect" it has, I suspect. If I had a way to remove them, I would but I am not a tinkerer like Matt.

 

I think the approach by Tesla with the side mirror-less is the way of the future. We have the tech to do it but I guess these giant car makers figure it cost an arm and a leg to do it right in a hybrid - thats why it takes a small specialist company like Tesla to show how its done. After all, even their "ipad" in the interior even has me swooning and goo-goo-gah-gahing.

 

 

@Matt - any chance for some pictures?

Edited October 9, 2013 by Jus-A-CMax

[C-MaxSea]

Jus, Matt, ....................  would there be any positive effect of folding in the mirrors - never mind, bad question.

 

BTW Jus, you do realize that you are the 'poster child' for no mods!  Tough to mod when it works so well without, eh!  (Although a case can always be made for minor & or cost effective mods)

 

Hope Matt checks in with some more input / pictures per my note #10.

 

Nick

[Jus-A-CMax]

Jus, Matt, ....................  would there be any positive effect of folding in the mirrors - never mind, bad question.

 

BTW Jus, you do realize that you are the 'poster child' for no mods!  Tough to mod when it works so well without, eh!  (Although a case can always be made for minor & or cost effective mods)

 

Hope Matt checks in with some more input / pictures per my note #10.

 

Nick

 

LOL, thanks....next time jus say I am completely unskilled with a screwdriver, a drill and don't even think about getting me near a hobby knife... :drop:

 

I think bottom line, as much as I luv the MPGs, I just like a "normal" car with no plastic covers or missing mirrors.

 

However....if I had the money, I would give my CMax to the Galpin Auto Sports (GAS) boyz in Van Nuys....Nick...you should see some of the work these guys do. They could do a side-mirrorless setup and do my car in a complete black stealth...complete with a lower carbon fibre scoop & molding....make my Maxine look like a F-117  stealth fighter, complete with the hard edging deturbulators. I haven't got into the interior yet. That would be my dream car..and it would prolly cost as much.

 

*sigh* time to wake up....

 

Yeah.

 

PS I am considering toying with these Gas Pods but I am not pulling the trigger yet. I don't really need it for my daily driving but where I think it will be much more effective is for my Mammoth or long trips when I go at freeway speeds. Still mulling....

Edited October 9, 2013 by Jus-A-CMax

[C-MaxSea]

Jus, It would be a hoot to see the GAS boyz stuff, to be sure!

 

Forgot to add that having so many of us doing great mileage without mods is very good, showing what is possible with just a little air.

 

Also forgot to mention that I am still expecting Ford to come through for us on a couple 'mods' for free, or nearly so - 2014 hood seal ...........  Hope I'm not dreamin, cause I seriously think Ford owes us even a little more, for being early adopters.

 

Nick

Edited October 9, 2013 by C-MaxSea

[Jus-A-CMax]

Lets hope so Nick but I am not holding out. The hood seal should be easy, I am surprised no one has come up with some clear plastic seal...if we can seal the doors, why not the hood...yeah, yeah, temps/heat...smeat.

 

Thats right with the other non-modded 600+ Mile Club members...Matt did some huge numbers before aero mods and he's still pushing the 700+ every tank just doing everyday driving like the rest of us, frbill, seth and many others as well. I have to let loose sometimes...hence my mid 600 tanks but I think I am keeping up with the Jones with my wee 3 x 800+ tanks,  etc. Jus takes me longer to do my tanks cause I don't drive as far, like I use to...which is good.

 

Aero modding adds more fun though, jus imagine the more miles....if you have the talent, money and skill to do it..ala Matt :)

Edited October 9, 2013 by Jus-A-CMax

[ScubaDadMiami]

Also forgot to mention that I am still expecting Ford to come through for us on a couple 'mods' for free, or nearly so - 2014 hood seal ...........  Hope I'm not dreamin, cause I seriously think Ford owes us even a little more, for being early adopters.

 

Nick

It doesn't sound like this is going to happen.  I can't remember the thread, but someone posted that finally got a response on this.  I think it was on the Twitter with Ford thread.

 

Basically, the answer was that it would not be possible to do retrofits for whatever changes they make for the 2014 model.  I don't know if this answer was only addressing things like the anticipated rear spoiler change or if it means everything and anything. 

[mtb9153]

LOL, thanks....next time jus say I am completely unskilled with a screwdriver, a drill and don't even think about getting me near a hobby knife... :drop:

 

I think bottom line, as much as I luv the MPGs, I just like a "normal" car with no plastic covers or missing mirrors.

 

However....if I had the money, I would give my CMax to the Galpin Auto Sports (GAS) boyz in Van Nuys....Nick...you should see some of the work these guys do. They could do a side-mirrorless setup and do my car in a complete black stealth...complete with a lower carbon fibre scoop & molding....make my Maxine look like a F-117  stealth fighter, complete with the hard edging deturbulators. I haven't got into the interior yet. That would be my dream car..and it would prolly cost as much.

 

*sigh* time to wake up....

 

Yeah.

 

PS I am considering toying with these Gas Pods but I am not pulling the trigger yet. I don't really need it for my daily driving but where I think it will be much more effective is for my Mammoth or long trips when I go at freeway speeds. Still mulling....

Jus, I have my first set of nine GasPods which are black and held on with 3M super sticky gel tape.  Would you like to give them a shot?  I'm not using them, just laying in a drawer in my garage.  LMK.

[Jus-A-CMax]

Jus, I have my first set of nine GasPods which are black and held on with 3M super sticky gel tape.  Would you like to give them a shot?  I'm not using them, just laying in a drawer in my garage.  LMK.

 

Thanks for your offer Mike, for the time being I am still pondering...still need to do some more research, if u know what I mean.

[fbov]

Research comes in 2 forms, looking for information that someone else gathered, and gathering information that others will look for. I think you mean the former while I'm going to talk about the latter, as my wife calls the car "my science project," and she's right! As to whether I'll gather data that others find useful, we'll see.

 

With a sample size of 1 (my car), and some 1-way updates (like 13B07 PCM), I'm doing a 1FAT study. That means I only change 1 Thing At a Time, then take copious data before making other changes. You see the affect of each change, but you get nothing on interactions among the test variables.

 

Test Design

- 2 standard test routes

High MPG - stop/go with 35-40 mph limits,

Low MPG - expressway with 55-65 mph limits.

- primary response variable is the location on a plot of MPG vs. Temperature

locus of points in a scatter plot

curve fit parameters (e.g. slope and intercept of a line)

statistical methods (e.g. ANOVA) when things are close

current data: 

 

Test Plan Phases

- Purchase/break-in by first owner (Oct. 2 - Aug. 9)

inherited the car from my Father-in-law

- Learning (Aug. 9 - Sept. 3)

I gave myself a month to learn to drive a hybrid consistently

- Baselining (Sept. 3 - Oct. 15 (I hope))

Try to drive with a consistent style over the two routes,

Interim results attached; strong temp effect in stop/go, but none for expressway??

- PCM Update (Oct 15 - it starts to snow)

Scheduled for Oct. 15

Timing is dealer- and weather-dependent; going to Vermont for Thanksgiving, and taking no chances!

- Snow tires (Dec - April)

While rated "LRR" I expect the tire change will be large

Using an aero wheel cover to blunt the increase in RR

- Aero Mods under consideration (April - October, 2014)

hood seal improvement

rocker panel skirt

chin spoiler on air dam

rear tire skirt (like the one on the front tires)

aero wheel covers

grill block

Kamm-style mod to lift gate

Gas pod-like devices

 

Notes on aero mods...

 

The only aero mod I've found that "fits the C-Max" is stick-on rocker panel skirt and air dam material. I would use it as-is for the skirt area and rear tire, trim it to height for the chin spoiler and front wheel skirt extension. I also think this is the stuff to fix the hood seal.

 

The current hood seal is bad; it only touches the hood at the ends, with an gap that fits fingers without compressing the seal. Plus, it ends at the grill, leaving the stretch to the headlight open. Wide tape would give a short-term fix, and I may test it that way to see if it's worth fixing. I'm thinking the rocker panel skirt material might be just the ticket for an openable seal; mount it to the underside of the hood and trim it where there's excess, like near the headlights. 

 

I'm making pizza pan wheel covers for the snows, but the concept only works well on steel wheels. The spokes on the c-max alloys leads me to look at brake shields as a better way to prevent air expulsion to the side. The only question is if the spokes themselves act as an aerodynamically rough surface, causing losses beyond the air injection issues... and now that I look at the price of Kleen Wheels, can I do something equivalent from a DIY perspective?

 

Grill blocks are low on the list because a) top grill is engine air intake and will benefit from hood seal, and b) the lower two grills both have louvres. We'll see what the 13B07 update does.

 

I'm hesitant to make bodywork changes, but that's what a permanent Kamm-back would involve. Conversely, all the aero guides I find say you only get big gains in Cd by mods in the rear. Perhaps Gas Pods are the no-bodywork equivalent? This is too far off to say what the next test might be.

 

Comments welcomed; there's a lot of things that could change the plan, but this is what I'm thinking today...

 

HAve fun,

Frank

Edited October 9, 2013 by fbov

[ptjones]

Here is the brochure I came up with in Feb. of this this year when temps. were cold.

 

Everyone I talked had an improvement of 2 or more MPG.

I have left my covers on all year long with no problems.

I'm currently working on wheel covers and expect 4% improvement.

 

Paul

 

Correct image attached
 

Edited October 10, 2013 by ptjones

[fbov]

Paul, your work was one of the first I looked at, as it well documents an improvement. I'm looking for new "low-hanging fruit." I notice that you only block the lower grills, the ones with louvres, and with the change in lourvre operation contained in the PCM update, I'm again going to leave that area alone. The upper grill looks like little more than a cold air intake for the ICE, and there's lots of open area behind the grill face to feed the plenum; it's hardly a pressurize feed. While I was at it, I also did hood seals.

 

Starting point

 

I pulled the plastic retaining plugs (pry up and remove cap, pry out plug) so I could access the area behind the upper grill. A little newsprint and a marker gave me a rough template, which I cut out in scrap plexiglass.

Here's it in place,with the grill pulled back. You can see the plexi best near the latch, where it's notched; reflections make the rest hard to pick out. It's bent slightly, so no rattle conerns.

And all closed up...

 

Next, hood seals...

Frank

 

 

[fbov]

Others have mentioned the gap at the front hood edge on either side of the upper grill, suggesting one lower the stops to close the gap. I looked at it from an aerodynamic perspective, especially when Ford announced mods for 2014 that include front hood seal modifications. The existing seal didn't seal; there was a air gap to the hood. There was also a gap a the edge of the hood all the way around, not just at the front edge.What to do?

 

For the hood seal, I added high density rubber foam weatherstripping to the underside of the hood where the existing seal is supposed to make contact.

Afer sitting overnight, you can see a crease in the rubber where the seal is making contact... and perhaps see how you can aim better than I did! That's the base of the latch at lower right.

I also used this material to build up a multilayer seal on the hood tall enough to seal outboard of the existing bulkhead-mounted seal, but left the center latch access open. This doesn't look reliable, so no pictures to prove I ever did it.

 

For headlights, I used a "bulb-style" silicone weatherstripping in clear.

I mounted it on the headlight itself, tucked in at the front and cut flush at the rear, and cross the upper grill facia where it meets the hood edge. The hood lead edge gap was larger than the weatherstripping could bridge, so I added a piece to the hood edge. At the other end, you could also continue past the headlight up to the windshield, but I didn't see a gap parallel to flow as being that important. If you like the look, it also fits the door jams; any where you get an 1.8" gap, but I suspect it's gong to be decorative

 

The hood now likes to be dropped to close, but it's tight and looks fairly clean with the clear being the only addition visible. (Using flash at dusk because I did this last night, the grill block this morning...)

 

HAve fun,

Frank, who couldn't wait until Spring to start doing the aero stuff.

 

PS remember, weatherstripping is designed to be used outdoors; it's designed to get wet and frozen and still stay put when you open gaps. the only risk I see is longevity, maybe some adhesive residue after removal...   

Edited November 2, 2013 by fbov