Hood splitter for my vw
 

Since I bought my VW last fall I have not done much to it. Changed tires, put a grill block on it. The weather had gotten colder mileage was still good but had dropped off to about 40 mpg.

Last week we had some weather approaching 70 degrees and I decided to take my last piece of election sign and make a hood splitter. I had also pulled the bottom of my grill cover out and attached it to the front of the bumper.

I carved it into a D shape and heat molded it with a propane torch. Right now it is duct taped on.
http://www.veloliner.com/vw/jettaprofile32011.JPG

Earlier this week I was driving in the rain and really noticed a change in the pattern of the drops on the windshield. The yellow lines mimic the pattern they made on the windshield.
http://www.veloliner.com/vw/jetta32011airflow.JPG

I can't say specifically the effect on the mileage. It may be good. I have 280 miles and it is just at 3/4 of a tank. Which is further than usual but not quantifiable.

Any comments on the air flow toward the center. None of the rain drops went past the center line of the windshield.

I may make some brackets and raise the back of the hood.

I was about to say forget it but upon further reflection I think everyone ought to concentrate all their efforts on this area, and let us know how it goes.

Well damn Frank. Who peed in your Cheerios ?

Let us know how the tank works out Varn.

I have seen wiper deflectors thet have slightly upped FE and wondered if a larger one would help.

Somebody has a large one on a pick up, ummm, BamZipPow? Big one that goes across most of the hood and is around 6" high. Worked for him.

How about making it wider, like at least the width of the hood ?

Aerohead has a big deflector / fairing that reduces the hood/windshield angle.

If it's on his truck, you know you want it, too ;)

Nope...not mine. Yer thinking of Aerohead's T-100... ;)

From a safety aspect...don't do that. There are specific safety catches on the fenders that are there to prevent the hood from flying over the vehicle in a front end collision.

Yer better off building it up from foam/Coroplast sheeting... :D

That's just Frank being Frank, he's blunt but he means well

Well, seeing as how there were several conversations going on this exact topic, very recently, and I felt they were conclusive i.e. sufficiently explored and explained, and aerohead's explanations were quite clear and had merit, and yet here we are... so it seems to me a bit less like pee in Cheerios and a bit more like peeing into the wind? :p

http://ecomodder.com/forum/showthrea...n-16329-4.html

http://ecomodder.com/forum/showthrea...flow-7116.html

http://ecomodder.com/forum/showthrea...tml#post227994

http://ecomodder.com/forum/showthrea...test-6155.html

I think this has potential.

EDIT: [I just saw Frank's post, which went up while I was writing mine. If this topic is already addressed and "laid to rest" as not significantly helpful, then that pretty much wraps it up. HOWEVER, if there is gain, it looks like low hanging fruit - you probably could build a full-width version as I described below pretty quickly and easily.]

I think that though you're calling it a splitter, most of the air it affected is going up over the windshield without really hitting it. Which I think is a good thing, and more helpful than if you had split the air off to the sides.

I'm guessing this from the "sunburst" pattern on each side of the windshield. If the air had been split, each side of the windshield would have a set of more parallel streak lines, going either up the windshield or maybe off to the side. But not a sunburst pattern.

So you've helped the flow of the air going up the middle of the hood. That's my guess.

So to get more benefit, widen the device out to the edge of the hood, or even out over the fender if you can make that happen. My idea is to scoop most of the air off the hood so it skips over the windshield. Keep the top rear low enough so that even a driver shorter than you can still see the same line down over the hood's forward edge.

And to keep it safe in a collision, make it out of coroplast. So if the hood flies up, or if your mod flies off the car, it doesn't cause damage. You might have to make it collapsible or removable, just so you can check the oil.

Why fool around? Go all in or go home!

http://ecomodder.com/forum/showthrea...tee-13405.html

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