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Re: Interest in lowering springs

Posted: Thu Jun 23, 2011 10:36 pm
by DaveEV
The suspension changes are primarily to firm up the suspension a bit so that it will handle a bit more predictably and "float" a bit less. Many feel that they have less control over the vehicle when the suspension is too soft.

1-2" lower is not a significant amount but will slightly improve the visual appeal - the car appears a bit "lifted" stock.

I doubt that there will be any significant or measurable aerodynamic benefit, though in theory it should help. Maybe the guys at ecomodder or cleanmpg have measured the benefit on other cars. Since the bottom of the LEAF is already very clean - most of the benefit will come from tucking the wheels/tires into the fenders a bit more.

Re: Interest in lowering springs

Posted: Thu Jun 23, 2011 11:54 pm
by TonyWilliams
It's good to know that we have fuel, a jack, and a spare tire.


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Re: Interest in lowering springs

Posted: Fri Jun 24, 2011 12:27 am
by mark13
I would be interested in the upgrade.. 8-)

Re: Interest in lowering springs

Posted: Fri Jun 24, 2011 6:09 am
by aqn
drees wrote:I'd be interested.
Ditto.
drees wrote:Would also be interested in some struts/shocks with more low speed damping to go with them, too.
Ditto. In fact, I'd only need stiffer dampers; I don't really need shorter/stiffer springs that much. Less body lean and a lower look are both nice, but body lean is not what bothers me about the LEAF's handling, and I don't really need a lower stance.

I don't mind the tall soft spring and copious body lean, handling-wise. It's toss-up between those and the tires as to which is the limiting factor. I do agree that the LEAF can use more damping (note: "damping", NOT "dampening"!!! Sorry, pet peeve of mine).
drees wrote:EDIT 2: Forgot about the rear beam axle - not going to get coilovers on back there so springs/shocks are the only option.
Just to clarify: a torsion beam suspension does not necessarily requires a separate-spring-and-damper set-up (and thus not suitable for "real" coilovers). It happens that the LEAF has separate spring and damper ("shock") on its torsion beam, but there are cars with torsion beam rear suspension that have concentric spring and damper set-up, and thus can accept "real" coilovers. For instance, watercooled VWs up until about mid-2000s.

Re: Interest in lowering springs

Posted: Fri Jun 24, 2011 6:10 am
by aqn
Skywagon wrote:I would like 0.5 to 1 degree of negative camber in the front to help with turn-in.
drees wrote:Anything in that range would be good for the street.
drees wrote:Edit: If the information in this post is correct - it appears that it may have enough negative camber dialed in already, but a little more never hurt. :)

http://www.mynissanleaf.com/viewtopic.p ... ent#p98414
I have no clue whether/how much negative camber would help with turn-in. On my VWs, I run more negative camber in the front to make the front sticks more/understeers less (since it would retain more negative camber); more negative camber does not seem to do much for turn-in response. For quicker turn-in, I run a small amount of toe-out in the front. Excess toe-out causes "wandering" at speeds, but my experience with my VWs is that with a small amount of toe-out (0.5 degrees or less per side) there's some wandering but it's barely detectable.

I don't know how much is "enough negative camber" I since my experience with VWs most likely won't apply to the LEAF, although they both have MacPherson strut front suspension and torsion beam rear suspension (up to the Mk IV's), given the differences in geometry, weight, weight distribution, etc. If I want to try a different alignment, I'd need to play around with different alignment settings. For example, on my A3 GTI, I ran -2.1 camber and 0.4' toe-out. For me, the jury is out on whether making the camber more negative would make the LEAF stick any better in turns, ditto adding more toe-out to improve turn-in response, because any alignment changes may just be lost in the under-performance of the tires. It's hard to say.
drees wrote:Gotta find out what the stock alignment specs are - suspect the settings are very mild.
As indicated, the LEAF has about -1 degree camber and just about straight-ahead toe. It would appear to be "very mild" but that's just a guess, since there are so many other variables.

Re: Interest in lowering springs

Posted: Fri Jun 24, 2011 6:10 am
by aqn
ERG4ALL wrote:Are these changes purely for the looks of the vehicle or does anybody have any data that would indicate a slightly longer range (i.e. less wind resistance)?
I wouldn't mind a less severe 4x4 look for my LEAF, but appearance is secondary to me. Ditto range, when it comes to suspension tweaks. I kinda doubt if there are any measurable changes in range resulting from a suspension change. A lowered LEAF might have less aerodynamics drag (though I don't know why; a lowered LEAF still has the same cross sectional area), but I wonder if it's measurable.

I do want a better suspension for the 5% of the time when I "get into it" a bit in the twisties, and for when things go pear shaped and I need to get out of Dodge to get out of the way of a Dodge.
ERG4ALL wrote:I suspect that the LEAF has a somewhat "squirrely" feel especially in wind is because they have limited the amount of "toe in" in order to reduce scrubbing and increase mileage.
That's a very interesting observation about less toe-in to increase efficiency. I don't have any complaints about the LEAF's behavior in day-to-day driving. It feels squirrely in the wind probably both from the soft suspension as well as from the broad-side-of-a-barn profile.

Re: Interest in lowering springs

Posted: Fri Jun 24, 2011 9:03 am
by Herm
Note, a "coilover" is a device that combines the coil spring with a shock absorber in one unit, mostly used in McPherson strut suspension systems.

If you guys are interested in increasing range first pump up your tires to max sidewall (and beyond if you are not chicken).. then see how it feels and handles before you start changing components.

Re: Interest in lowering springs

Posted: Fri Jun 24, 2011 12:24 pm
by mxp
Yes. I am interested as well.

I prefer to keep the factory shocks and have a vendor tune the lowering springs to factory shocks for a consistent and tight ride.

Most people forget that there is still an "installation cost" and a "wheel alignment cost" that needs to be factored into this project. Therefore, I felt a Leaf "coilover solution" as a product would be more expensive.

Coilovers are great for more customization, like user configurable height and other factors which could turn your Leaf into a weekend track car and reset back to daily driver on week days. But, unless there is a comparable cost to coilovers and installation costs, only then I would I consider it.

Re: Interest in lowering springs

Posted: Fri Jun 24, 2011 12:30 pm
by DaveEV
aqn wrote:I don't know how much is "enough negative camber" I since my experience with VWs most likely won't apply to the LEAF, although they both have MacPherson strut front suspension and torsion beam rear suspension (up to the Mk IV's), given the differences in geometry, weight, weight distribution, etc. If I want to try a different alignment, I'd need to play around with different alignment settings. For example, on my A3 GTI, I ran -2.1 camber and 0.4' toe-out. For me, the jury is out on whether making the camber more negative would make the LEAF stick any better in turns, ditto adding more toe-out to improve turn-in response, because any alignment changes may just be lost in the under-performance of the tires. It's hard to say.
I would bet money that more negative camber will improve grip - at least up to 2* like you ran on your GTI even on stock tires. On my WRX I had a big sway bars and stiffer springs and even at 1* it could have used more camber looking at the tire wear. The fact that the rear stock spec between 1-2* verifies this. Get the fronts set the same as the rear (about 1.5*) and I'd bet it'd be pretty balanced.
Herm wrote:If you guys are interested in increasing range first pump up your tires to max sidewall (and beyond if you are not chicken).. then see how it feels and handles before you start changing components.
Already done - 44 front and 42 rear. Improves road feel slightly from how it was delivered (about 39 psi all around) but doesn't alter handling feel to any noticeable degree.

Like the others, I feel the biggest deficiency is the lack of low speed damping in the stock shocks - things can get a bit floaty over undulations in the road.

Re: Interest in lowering springs

Posted: Sun Jun 26, 2011 4:45 pm
by MrFish
I contacted Eibach to let them know there would be 4 or 5 Leafs here interested and I am waiting to hear back from R&D.
Ill keep you posted.