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Discussion Starter #1
I was looking to help my rear suspension in the Geo
Metro.

I found out that canev has replacement coil springs
for about $265, and coilsprings.com can do it for
$187...

But what about air springs, and air bags...does anyone
know a good link to find out which one is good for my
car?

thanks

Michael Golub

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Discussion Starter #2
Hello Mike,

Look at www.ridetech.com

On my 1977 El Camino, I use the Air Shock Wave system. These units replaces
both the springs and shocks for any weight from very lite sport cars to
heavy trucks.

My EV with the standard suspension would be 7/8 of a inch lower in the back
with the standard Monroe Air shocks pump up to 100 psi. I found that I can
lower the front to level up the EV with the Air Ride System.

Roland




----- Original Message -----
From: "mike golub" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Tuesday, August 14, 2007 9:42 AM
Subject: [EVDL] Air Springs


> I was looking to help my rear suspension in the Geo
> Metro.
>
> I found out that canev has replacement coil springs
> for about $265, and coilsprings.com can do it for
> $187...
>
> But what about air springs, and air bags...does anyone
> know a good link to find out which one is good for my
> car?
>
> thanks
>
> Michael Golub
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

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Discussion Starter #3
I'll be using these (single adjustable) in the back of my truck:

http://tinyurl.com/29qgzf

and I'm planning on using these (double adjustable) in the front:

http://tinyurl.com/2fc7ms

What bothers me though, is how the weight is supported. With the stock
shocks and springs, the weight of the vehicle was supported mainly by
the springs -- two large leaf spring mounts per side in the rear, and
the large stock A-arm cups in the front.

By using integrated shock/spring units like these (it would be the same
if I'd gone with coilovers), I'm now concentrating the significantly
increased weight of my EV on just 4 shocks. And it's not like I get to
use big bolts either -- the holes they provide take a 1/2 inch bolt,
which just doesn't seem like very much metal between me and disaster.

How safe is this? Am I asking for one of these mounting bolts to shear
off on a hard bump and ruin my day? The rear will have custom-made
mounting points for the shocks, as the rear frame is being redesigned
anyway; I can build them however I want. For the front shocks though, I
was considering just mounting the shocks in the stock location, but I'm
wondering if it will be strong enough...

--chris



Roland Wiench wrote:
> Hello Mike,
>
> Look at www.ridetech.com
>
> On my 1977 El Camino, I use the Air Shock Wave system. These units replaces
> both the springs and shocks for any weight from very lite sport cars to
> heavy trucks.
>
> My EV with the standard suspension would be 7/8 of a inch lower in the back
> with the standard Monroe Air shocks pump up to 100 psi. I found that I can
> lower the front to level up the EV with the Air Ride System.
>
> Roland
>
>
>
>
> ----- Original Message -----
> From: "mike golub" <[email protected]>
> To: "Electric Vehicle Discussion List" <[email protected]>
> Sent: Tuesday, August 14, 2007 9:42 AM
> Subject: [EVDL] Air Springs
>
>
> > I was looking to help my rear suspension in the Geo
> > Metro.
> >
> > I found out that canev has replacement coil springs
> > for about $265, and coilsprings.com can do it for
> > $187...
> >
> > But what about air springs, and air bags...does anyone
> > know a good link to find out which one is good for my
> > car?
> >
> > thanks
> >
> > Michael Golub
> >
> > _______________________________________________
> > For subscription options, see
> > http://lists.sjsu.edu/mailman/listinfo/ev
> >
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev

--
Christopher Robison
[email protected]
http://ohmbre.org <-- 1999 Isuzu Hombre + Z2K + Warp13!

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Discussion Starter #6
storm connors wrote:
> I just noticed the price! A spring shop could put extra leaves in your
> leaf springs for a lot less money. Replacing coils with heavier ones
> is also relatively cheap too. Why not do it right, especially if it is
> cheaper.

I am putting a 4-link suspension in the back, hence, no leaf springs.
Also, I like these units as the bounce and rebound are independently
adjustable, in the dual-knob version. (They're like Konis, but easier to
adjust without removing the shock.)

One possibility for the front at least is their bolt-in product, which
replaces just the shock absorber and allows you to use the stock springs
(or in my case, replacements with a higher spring rate). I'd lose the
ability to adjust ride height and spring preload, though.

Another option is just replacing the A arms with tubular aftermarket
arms designed for use with a coilover setup. They'd end up a lot
lighter.

Still mainly worried about the rear sitting on those bolts (which will
have a LOT of battery weight on it, and potentially some cargo) but if a
1/2 inch grade 8 will take the load, then I can make a decent
double-shear hard point for it out of 3/16 or 1/4 plate, that hopefully
won't let go.

--
Christopher Robison
[email protected]
http://ohmbre.org <-- 1999 Isuzu Hombre + Z2K + Warp13!

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Discussion Starter #9
Yup. I used to work for a plastics manufacturer who closed their doors
to go full time into the air bag buisness. I have watched the testing
and helped cut up bags and can say without a doubt, these guys have a
great air bag.

http://www.slamspecialties.com/

When you talk to Nick, you are talking to the original owner of the 300Z
that I converted.

This sounds like an endorsement,but really it is just facts. They are
designed in such a way that they don't expand in diameter when inflated
and don't come apart if inflated without being constrained. They also
use a special process(not sure if I should say more), that prevents leaks.

The bags are stiff enough to act as the dampening, often times where
shocks went through center of spring, guys get away with leaving the
shocks off.

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Discussion Starter #10
There is a golden rule, never locate on springs*. Unfortunately leaf
springs in pickup trucks have violated this rule for years. To fix that
you weld in a 4-bar link.

*may that is my variant of never locate with bolts.

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Discussion Starter #11
will he give us a good price?
--- Jeff Shanab <[email protected]> wrote:

> Yup. I used to work for a plastics manufacturer who
> closed their doors
> to go full time into the air bag buisness. I have
> watched the testing
> and helped cut up bags and can say without a doubt,
> these guys have a
> great air bag.
>
> http://www.slamspecialties.com/
>
> When you talk to Nick, you are talking to the
> original owner of the 300Z
> that I converted.
>
> This sounds like an endorsement,but really it is
> just facts. They are
> designed in such a way that they don't expand in
> diameter when inflated
> and don't come apart if inflated without being
> constrained. They also
> use a special process(not sure if I should say
> more), that prevents leaks.
>
> The bags are stiff enough to act as the dampening,
> often times where
> shocks went through center of spring, guys get away
> with leaving the
> shocks off.
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

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Discussion Starter #12
I dunno. There was talk of that when I worked there, but that was over a
year ago. Maybe I could become a distributer for the list, I could look
into that.

I seem to remember they were really reasonably priced. I was surprised.
Since they can handle the pressure you can get a smaller diameter bag
and put more air pressure in it to give you the same lift as a larger
diameter bag at lower pressure, but the ride changes.


IIRC, there is a pressure rise when you go over a bump and for 1" of
travel, this rise is different on an 8" diameter bag vs a 5" diameter
bag. I think the small bag on higher pressure is stiffer than the larger
bag on lower pressure. This acts like the difference between a shorter
stiffer spring and a softer spring with more preload.

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Discussion Starter #13
will these crack at -40 degrees?
--- Jeff Shanab <[email protected]> wrote:

> I dunno. There was talk of that when I worked there,
> but that was over a
> year ago. Maybe I could become a distributer for the
> list, I could look
> into that.
>
> I seem to remember they were really reasonably
> priced. I was surprised.
> Since they can handle the pressure you can get a
> smaller diameter bag
> and put more air pressure in it to give you the same
> lift as a larger
> diameter bag at lower pressure, but the ride
> changes.
>
>
> IIRC, there is a pressure rise when you go over a
> bump and for 1" of
> travel, this rise is different on an 8" diameter bag
> vs a 5" diameter
> bag. I think the small bag on higher pressure is
> stiffer than the larger
> bag on lower pressure. This acts like the
> difference between a shorter
> stiffer spring and a softer spring with more
> preload.
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

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Discussion Starter #14
-40degrees burrrr. I don't have any idea.

I was trying to calculate spring constants and I may be completely wrong
about the difference in ride between different diameters. So don't quote
me on that yet.

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