Has anyone tried a front splitter in a Gen 2 for lower drag?

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That big British car show did it on a gas car and got nothing. I suspect unless you have a wind tunnel (or the relevant software that replaced wind tunnels) they are pointless. “Close” apparently does nothing.
 
OK...point well taken. I will still take measurements to see if it would fit well...it would really change the front-end looks. If it is not a good fit I will probably do a 2" lower rubber scraper chin.
 
Isn't a splitter used to increase front downforce ?
The side effect of creating downforce being more drag ?
A splitter on a race car is very low to the ground and often goes forward a bit to be effective
DSC_5907-scaled.jpg


Wouldn't an air dam be a better device for increasing range ?
An air dam is a device used to divert air from going under the vehicle helping to reduce drag and sometimes used to stop or reduce lift.
mvc-008s.jpg

I put an air dam on the front of a RV which improved fuel mileage 10%.
It was low enough to rub the ground on occasion.
Bottom few inches was a stiff rubber material.
 
Yes...As my post above...I'm now leaning towards that.....I measured the side of the front bumper skin against the air splitter & I think it wouldn't really work ....too much gap between the splitter & the forward edge of the wheel well ----I think that it would look wrong..... So, I'm going to buy a rubber chin -- https://www.ebay.com/itm/402537943923 looks pretty good.
 
Isn't a splitter used to increase front downforce ?
The side effect of creating downforce being more drag ?
A splitter on a race car is very low to the ground and often goes forward a bit to be effective
DSC_5907-scaled.jpg


Wouldn't an air dam be a better device for increasing range ?
An air dam is a device used to divert air from going under the vehicle helping to reduce drag and sometimes used to stop or reduce lift.
mvc-008s.jpg

I put an air dam on the front of a RV which improved fuel mileage 10%.
It was low enough to rub the ground on occasion.
Bottom few inches was a stiff rubber material.
No sure. There are a lot of things that can be done with aero. There might be something novel.
 
An air dam like the Chevy Volt might be the most sensible option:
TokNZiql.jpg

Though the Volt has a much less aerodynamic undercarriage than the Leaf, it's possible the gains from the drag reduction will be outweighed by the increased frontal area.

Being a frequent lurker on Ecomodder has taught me one thing: you should always test modifications, and not just assume they make a difference. Maybe I get inspired to put an air dam on my Leaf and try to measure the differences. A coast down test should be a pretty good indicator for aerodynamic drag.
 
Well...I'm going to try a chin rubber....I am getting a good feel for the usage in the first part of my trips (up & down a hill--then 55 mph for 8 miles with a round-a-bout halfway through (55 to 50 to 45 to 20 & back)....So I "should" be able to quantify usage within a week or so after installing it..... We will see.................. I just put in ULV diff fluid (the old fluid was really bad at 30K)....so I should have enough time to see that before the chin. I've been right at 4.3/4.4 Kwh for that run right now.
 
Well...I'm going to try a chin rubber....I am getting a good feel for the usage in the first part of my trips (up & down a hill--then 55 mph for 8 miles with a round-a-bout halfway through (55 to 50 to 45 to 20 & back)....So I "should" be able to quantify usage within a week or so after installing it..... We will see.................. I just put in ULV diff fluid (the old fluid was really bad at 30K)....so I should have enough time to see that before the chin. I've been right at 4.3/4.4 Kwh for that run right now.
*Momentarily fails to understand. The mental picture is entertaining*
“Don’t they call those dental dams?
 
A splitter isn't going to help, as a technical term a splitter is specifically a downforce instrument - an inverted wing at the front to push the front wheels harder into the ground. It's going to add rolling resistance and induced drag, so definitely a net negative on range.

An air dam is a better idea. The idea of an air dam is that air coming at the front of the vehicle is forced underneath the car, where it encounters all kinds of irregularities that cause drag. It's better for all that air to instead be diverted to the sides of the car, where it can freely flow and cause much less drag.

However, an air dam ALSO causes much less air to exit the rear of the vehicle, which then causes a larger, lower-pressure wake to form, increasing drag. So if you're going for a front dam, you should definitely also consider some kind of wake mitigation in the back. Boat tails are obviously the best, but practically unworkable. Kamm backs are easier to do and there have been some really practical ones through the years that have worked surprisingly well.
 
A splitter isn't going to help, as a technical term a splitter is specifically a downforce instrument - an inverted wing at the front to push the front wheels harder into the ground. It's going to add rolling resistance and induced drag, so definitely a net negative on range.

An air dam is a better idea. The idea of an air dam is that air coming at the front of the vehicle is forced underneath the car, where it encounters all kinds of irregularities that cause drag. It's better for all that air to instead be diverted to the sides of the car, where it can freely flow and cause much less drag.

However, an air dam ALSO causes much less air to exit the rear of the vehicle, which then causes a larger, lower-pressure wake to form, increasing drag. So if you're going for a front dam, you should definitely also consider some kind of wake mitigation in the back. Boat tails are obviously the best, but practically unworkable. Kamm backs are easier to do and there have been some really practical ones through the years that have worked surprisingly well.
*googles “kamm backs”*
https://en.m.wikipedia.org/wiki/Kammback
Ah so a truncated boat tail a la late model corvettes.
 
I agree with others that a splitter will not help. I do not think an air dam will help either, as the undercarriage is relatively aerodynamic.

That being said, I've been contemplating air deflectors to divert air away from font tires only. The stock ones are relatively small.

I'll be tuning in for your updated results.
 
Hmmmmm.... Thank You All for thoughtful responses.... Very good food for thought. I'm getting the rubber I posted above from eBay in the next couple of days & am thinking how to use it right now. I'm liking the idea of doing a right & left side air dam to be more effective than the current under-chin parts... Will play with the center spacing to see how it looks/may work...... I'll have enough material to try it a couple of ways.
 
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Hmmmmm.... Thank You All for thoughtful responses.... Very good food for thought. I'm getting the rubber I posted above from eBay in the next couple of days & am thinking how to use it right now. I'm liking the idea of doing a right & left side air dam to be more effective than the current under-chin parts... Will play with the center spacing to see how it looks/may work...... I'll have enough material to try it a couple of ways.
Well testing will tell. If you get a mileage bump it works. If you don’t it doesn’t.
 
I just ran across the factory front "spoiler" The part# is 62084-5SNOA & it looks like it is the same dark blue as the rear trim......I'm still going to create a left & right underside air deflector that is more than what is there right now, but I may just order the stock part from Nissan to install & see what differences it makes. The note indicates that the part was installed only on the 62kWh cars.
 
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That's interesting that it was only on 62 kWh cars. Maybe that has something to do with the battery pack hanging 40mm lower than the smaller ones?
 
Very good question...if I were to make a guess---that sounds about right. The Nissan Parts page just gives a generic description: "A vehicle body part mounted flush to a body panel used to work with a vehicle aerodynamics used to create less drag and increased aerodynamics." I'm going to contact the local dealer & see what the real cost is & how long it takes to get one. The Southern California dealer website I got the information from showed a cost of $168 USD.
 
Well...The eBay part was NOT very good....I tried a basic extension to the air deflectors....this is a very first take on it...have ordered a 3" wide X 1/8 thick rubber roll from Amazon to drop the stock deflectors & do a more effective outer like my first try....

I'm ordering the 62KWh front air dam on Monday.
 

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