New front air dam
 

I thought it was time that I stopped just reading about mods and tried experimenting with one so I built a front air dam last weekend. I'm quite happy with the look (the less important part) but I'm not sure yet if it is going to help MPG. I already mounted a partial front pan last year and redid my grillblocks in the fall. Lowest suspension parts are at 6" and bottom of dam is 5.5". Eventually I would like to do a full pan and widen the front bumper to clear the tires but that is not an outside project at -20c. Anyway, I had a 200mile highway run yesterday that I make occasionally and mileage was only 8L/100km avg. at 65-70mph but -20c to -12c temp may have had some effect. I avg around 7.6-7.8 in the summer if the winds not blowing hard. I need to do some sort of A B A test when it warms up to be sure I guess. It may be too low or maybe I should have left the middle open. It may be creating more turbulance at the front tires since it doesn't clear them even though I tried to deflect it out at the end. I would appreciate your feedback. I was going to post pictures but apparently the file sizes are too big.:(

puddleglum -

The album feature will upload any size JPEG. Go as follows :

User CP -> Pictures & Albums -> Add Album

Create an album and add a picture to it. The album will automatically downsize the image to fit. Then click on the picture and you will have a "BB Code" text of the image that you can copy into your post.

CarloSW2

i'm so confused. you talk mpg, mph, & 200 miles. but you posted 8L/100km.
so i did some research.

you got 29.40 mpg
according to this site: http://www.pege.org/fuel/convert.htm

Carlo, thank you for the help, I'll try this again. Luvit, sorry about being confusing. I was trying to use US terminology, but I do everything in metric and I didn't take the time to work out the conversion.

Here is my second gen. grill block with adjustable lower baffle and the pan before adding the air dam.
http://ecomodder.com/forum/member-pu...re1521-004.jpg

http://ecomodder.com/forum/member-pu...re1526-005.jpg

This is the filler pieces I built to tie into the small factory air dam and a piece of vinyl siding starter strip and some rubber cove molding that made the air dam.
http://ecomodder.com/forum/member-pu...re1520-003.jpg

Here is some assembly and the finished product.
http://ecomodder.com/forum/member-pu...re1523-007.jpg

http://ecomodder.com/forum/member-pu...re1524-008.jpg

http://ecomodder.com/forum/member-pu...re1522-010.jpg

http://ecomodder.com/forum/member-pu...re1525-009.jpg

Sorry that some of the pictures are dark but please tell me what you think. I

grill blocks look great!
by the way, how cold has it been for you this week?

lows have been around -5 to -15F with windchills -15 to -25F. Highs around 0 to 10F. Not as bad as a few weeks ago, hit -40. It's supposed to warm up this weekend though.

puddleglum -

Excellent execution! I like your choices of materials. We usually see garden edging for this kind of stuff.

I see you have a block heater "ceegar" (plug), so to speak, ha ha. ... Or maybe a battery trickle charger plug?!?!?

CarloSW2

That is one of the cleanest set of mods I've seen. Looks totally stock!

BTW, What kinda vehicle is that? I can't place it.

Clean looking work.

It'd be great if you make a garage entry for the car. Then we'd all be able to figure out what it is. :)

Love the grille block. It almost looks like a factory option!

Thanks for your encouragement. My goal is to find a way to do mods that help mileage and look good as well. Now I just need to determine if it's really helping mileage. I did the garage entry but is there anyway to enter mileage in metric? Oh, yes that is a block heater plug. They are standard equip. here. Everybody has them.

Very nice work! That siding starter strip is a great idea and the cove molding looks like it belongs!

I know you're in a cold area, but I'm curious if the little peephole you left open is enough for when the weather gets warmer?

No it's not. That will only do for around town when it's cold. The center pieces slide in behind the outer ones so it can be opened up as needed. When opened up it was okay on the highway to 50 F last fall so if I'm in town it will be good for warmer than that.

I wanted to post an update on my airdam. I made the same trip last friday as I did before. I've been thinking that I may have made it too long since it was an inch below the rest of the underbelly and initial results were not stellar. Anyway, I decided to pull it back off except for the tin brackets. This left me with around a 2" air dam. the temp was warmer (steady at around 20F) and almost no wind for either trip. My trip up mileage was a little worse, a little over 28 mpg but there was freezing drizzle and fog in the morning this time which may have had some effect on results. On the trip back, though, I got 31.3 mpg. I've decided that I need to take an inch off the rubber when I put it back on and I think it will work better. I'm also not entirerly happy with using the tin for support brackets. I hit some ice in a parking lot and bent the center bracket already. The rubber folds under and comes back nicely though

Well the test results are in. I decided to do an A-B test before I reinstalled my modified air dam. I replaced the tin center section with plastic (old siding) and I shortened the center of the rubber to 2.25" and tapered it down to 3" on the ends.
got some black screws to install the rubber this time and it looks even better than before. Sadly though, It is a failure. I made three two way runs without the air dam. Weather was not ideal but result was consistant. At start of test, temp 14F, S wind 9.4mph, Baro. 100.0kpa and runs were east and west at 70mph. Avg for two way runs was .83 liter and 27.04mpg. Installing the air dam took a little longer than I thought so I only had time for one two way run with it on and I had to turn the lights on. Wind had changed to SSE 11.2mph and baro. 102.4kpa with fog. With the air dam, I used .83 liter and got 26.88mph. Very discouraging, just a waste of ime and money:( I don't know if it is redundant because of the partial belly pan that I had already or if it didn't help because it doesn't fully clear the tire. Any thoughts?

I think you should give it another shot when the weather breaks and clears up. I'm fairly certain your gains were lost to the minute changes in weather, temperature, and the fact that you had to run 200w of lighting.

I'd be reluctant to declare this either a success or a failure without very controlled testing. The difference between the two airdam sizes will be very small regardless.

I had taken the air dam off to modify it and the A test was done with no air dam. The only part of the dam that I didn't remove in the A test were the outer deflectors in front of the tires. I'm going to leave it for now, but I'll probably experiment with something different in the spring.