Suspension Upgrade Possibilities?

[JimSouCal]

Thank you all for ALL of the suggestions, outlinks, and fleshing out of the issues. It seems that some of us will be working to tighten up the ride a bit. And there is a possibility that the demo car I drove had under-inflated tires that compounded the spongy handling when I drove the car. Improvement is worth a bit of time and effort for me.

And yes, running your car around cones in a does prepare you for some of those unplanned events. Maybe an afternoon as guests at another event running LEAF against LEAF might be fun safety training

I am still researching the matter... Scott at Fontana Nissan contacted me, and I am wondering what he may suggest. Will report back.

 

[nader]

My brother has some friends that work at KW Suspension in Sanger. He is checking with them to see if they would be interested in developing a kit for the car I dont think it needs coilovers. Just a balanced set of springs and shocks/struts with a mild drop will do. Lower ride height = improved aero! Now if only my car would show up then they would have a car to use for development!

 

[garygid]

Or, with the LEAF's covered underbody, would one raise the body higher for less aerodynamic drag?

 

[DaveEV]

Lowering the car will reduce aero drag from the wheels / wheel wells, but I see your point, Gary. If only we had a wind tunnel...

 

[garygid]

I seem to remember that Aptera was trying to keep the body higher to keep the drag down.

 

[nader]

My comment was based on the assumption that the less turbulent air that moves under the car, the less drag. Similar in racing, where they use a large front splitter very close to the ground to direct air around the vehicle instead of under. In the case of the Aptera (just got my deposit back btw) and it's wing shaped body it makes sense for ait to be able to move under the car too.

 

[JimSouCal]

Lowering the car will reduce aero drag from the wheel wheels, but I see your point, Gary. If only we had a wind tunnel...

Others have pointed out that the battery pack is more likely to hit bottom with the car lowered. The low center of gravity of the car, and a higher loading would effect how this plays out, I'd think.

As far as lowering goes, I am reluctant to pursue that angle for the aforementioned reasons...

 

[nader]

Some wheels, tires and alignment will likely go a long ways, but be prepared to take some efficiency hit depending on the tires you end up with. The stock size rear tires off the Tesla may be a good candidate (Yokohama Neova AD07 LTS 225/45/17) as supposedly they have pretty low rolling resistance for their grip level...

The stock EP100 tires are also available in 215/45/17 but the service rating (87W) is a bit lower than the stock tires (91V). These tires are about the same overall weight as the stock tires (21 vs 20 lbs) and a lot lighter than the AD07 (25 lbs). Of course, they won't grip as well, either.

If you head to tirerack.com you can see what tires are available and full specs. 215/45/17 or 225/45/17 would be a good +1 tire size for the Leaf as it will keep your odometer/spedometer readings very close to the same.

I would also love to see some mild sport springs available as an upgrade. I have some now on my WRX and vastly prefer them over the stock springs.

A 205/50/07 would preserve the factory 25" OD. A quick search on tirerack for 205/50/07 with a lor rolling resistance rating (LRR) shows a few viable options.

http://www.tirerack.com/tires/TireSearchResults.jsp?filtering=true&width=205/&ratio=50&diameter=17

I like this route because it will keep the contact patch a bit smaller vs. 225 width tires and the improved looks of plus sizing. There are tons of light weight 17" wheels too in the 5x114.3 bolt pattern.

 

[DaveEV]

As far as lowering goes, I am reluctant to pursue that angle for the aforementioned reasons...

We're not talking about anything significant - 1-2". Nothing that would significantly increase the risk of scraping the underside of the car.

A 205/50/17 would preserve the factory 25" OD. A quick search on tirerack for 205/50/07 with a lor rolling resistance rating (LRR) shows a few viable options.

http://www.tirerack.com/tires/TireSearchResults.jsp?filtering=true&width=205/&ratio=50&diameter=17

I like this route because it will keep the contact patch a bit smaller vs. 225 width tires and the improved looks of plus sizing. There are tons of light weight 17" wheels too in the 5x114.3 bolt pattern.

Yes, that would work well, too. 215/45/17 is also close enough in diameter and will provide a few more options.

 

[Electric4Me]

I don't intend to modify my Leaf at all, since it is going to be my wife's car and I have several others for sports purposes, but I will definitely take it to an autox or a performance driving school at least once when it arrives to safely test its handling at the limits of grip, so I know what to expect in an emergency situation.

TT

If I modify my Leaf it will have to be subtle so that it doesn't make my wife reluctant to drive it. I have my WRX for a toy. I may consider anti-sway bars at some point though, but first I need to spend some real time behind the wheel! I will definitely take the car to an autocross as I consider that essential driver's training & new car orientation.

Camber will like get adjusted though as stock understeer always drives me crazy!

 

[Skywagon]

I have the attention of Ksport and will let you all know if anything progresses. They already make coilovers for several Nissan compact cars (Versa, Cube, etc) so they should hopefully have no issues designing a kit for the LEAF.

 

[JimSouCal]

I have the attention of Ksport and will let you all know if anything progresses. They already make coilovers for several Nissan compact cars (Versa, Cube, etc) so they should hopefully have no issues designing a kit for the LEAF.

Thanks for the effort. They will take into account the greater mass (battery weight) of the LEAF, I suppose? And the, well, general frugal nature of the market segment, or one can hope?

 

[DaveEV]

Edmunds has a nicely photographed Leaf showing off the suspension and brakes.

2011 Nissan Leaf: Suspension Walkaround

It does appear that camber is not adjustable in the front and unfortunately the aux stabilizer bar in the rear twist beam axle is welded in place instead of being removable (like on many Toyota's for example).

The brakes are indeed very beefy - beefier than the brakes on my Subaru WRX for example.

 

[mwalsh]

It does appear that camber is not adjustable in the front and unfortunately the aux stabilizer bar in the rear twist beam axle is welded in place instead of being removable (like on many Toyota's for example).

But it looks like more negative camber could be introduced with the simple replacement of that stock lower arm with a slightly longer one. An opportunity for the aftermarket manufacturing crowd, methinks!

Wheel and tire 41.5lbs per Edmunds, eh?

 

[nader]

Remember that most aftermarket coil overs have one of the lower mounting holes slotted to allow camber adjustment without having to add camber plates or adjustable bolts.

 

[TomT]

I guess I am a little surprised by how plebeian, simplistic, and flimsy the suspension and suspension mounting points look, particularly the front... Perhaps I've just become accustomed to the more substantial materials in my other cars over the years... But then, they were more upmarket and less pedestrian... I just wonder how things like those small bushings are going to hold up over the long run in a car that is decidedly not light weight.

I'd love to see something from the after market to allow more caster to improve the return and self-centering/on-center forces.

Edmunds has a nicely photographed Leaf showing off the suspension and brakes.

 

[DaveEV]

But it looks like more negative camber could be introduced with the simple replacement of that stock lower arm with a slightly longer one. An opportunity for the aftermarket manufacturing crowd, methinks!

Aftermarket control arms are usually very expensive. A much more affordable option would be to replace one of the strut bolts (typically the upper) with an elliptical one. Eibach or someone probably already makes one that will work - just need to figure out which one.

Wheel and tire 41.5lbs per Edmunds, eh?

Yeah - given that the stock tires are about 20 lbs (as light as they get), ~20 lbs for the stock wheels is excessive. It's not hard to make 17 lb 16" wheels and 15 lb 16" cast wheels are not uncommon. Going significantly lighter will require forged wheels (expensive) but then you can get down to 11-13 lb range.

I'd love to see something from the after market to allow more caster to improve the return and self-centering/on-center forces.

Camber/caster plates should be the most affordable solution here. A side benefit (or drawback if you dislike NVH) is that the typically cushy upper mount will be replaced with a solid mount. The difficulty will be convincing a manufacturer to go through the R&D to produce a low volume part.

 

[Electric4Me]

*sigh*
I've always told myself that I won't buy a car without independent rear suspension, but here I go...

I'm sure camber bolts will work fine like you said. For those that don't know them, here's a pair I'm currently using:
http://tinyurl.com/4csjatm

I'm definitely surprised by the size of both the front and rear brakes! I could see a "performance mod" of downsizing them! :lol: They're bigger than on my WRX which came with 16" wheels and weighs 3100 lbs.

 

[DaveEV]

I'm sure camber bolts will work fine like you said. For those that don't know them, here's a pair I'm currently using:
http://tinyurl.com/4csjatm

You using those on your WRX? I was able to get a bit over -1 with the stock adjuster in front on mine, and the rear is already about -1.5 stock.

They're bigger than on my WRX which came with 16" wheels and weighs 3100 lbs.

Heh - another WRX owner. Unfortunately my WRX will be sold to make room for the Leaf - but ~22 mpg and 20c/mile in fuel does not make any sense!

 

[mwalsh]

Aftermarket control arms are usually very expensive. A much more affordable option would be to replace one of the strut bolts (typically the upper) with an elliptical one. Eibach or someone probably already makes one that will work - just need to figure out which one.

Huh. Never seen those before. Guess I'm getting to be too "old-school".