V90

[Kraske]

Matt's Lyx V90
So I've been playing with 7xx/9xx Volvo wagons for a while and figured I should make a thread. This is the latest stage of my disease: 1997 V90 wagon.
I've had my eye on owning one of these for some time but never figured I'd actually buy one. If you don't know, they're basically the ultimate version of the 7/9 series chassis:
RWD
DOHC in-line aluminum 6-cyl
body matched most pieces
interior ergonomics improvements
locking differential
...and the list goes on but unless you're a Volvo person you probably don't care ...









I picked her up back in October of 2010. She looked like this back then:







Tossed some 18" Work VS-TX on her to start with:








Then I wrecked her and melted basically the whole engine. So I replaced it in three days (1 out, 1 in, and one learning about Volvo starter inhibitor circuits):








Then I cut the front springs. The back uses a transverse fiberglass monoleaf like a Corvette so there was no easy way to drop it. Sport rake is cool right? No, not really. This only lasted about a month before getting put back the way it was.




Then I got a little distracted:

[Kraske]

Then I made an impulse buy:



AIRBOGZ?!

I’ve been a closet lowrider fan my whole life. However, I value my back. Air was the obvious compromise.
As I was browsing Craigslist one day I found a complete air suspension system for some random car (the owner wasn’t really sure). Since it was a steal of a deal, I took the ferry to Bremer-compton and picked it up.
The above was the result.




Before I go any farther I want to make a few things clear:

1. If you are looking for a professionally made and installed AIRRIDE (tm) kit, look elsewhere. I shouldn’t need to tell you that my work isn’t perfect. It was done on a college-student budget.
2. I used my engineering intuition on most of the calculations that should have been done here. I feel that my design is safe enough to be daily driven. If you don’t like it, feel free to tell me why but don’t clutter my thread with it. So we’re all on the same page with this:
WHAT I HAVE DONE IS NOT GUARENTEED TO WORK AND MAY NOT BE SAFE. DUPLICATE AT YOUR OWN RISK.
… now that that’s out of the way. I believe that my car and the modifications I’ve preformed are safe for daily use. Where appropriate I will mention my reasoning. Feel free to ask if you have any questions.
3. Performing similar modifications may result in contagious smiles and laughter. So what are you waiting for?

Okay, here we go…


Most McPherson air bag systems use a ‘strut bag’ that has a telescoping cylinder in the center so there is room for the damper shaft. This system was designed to seal to the damper shaft and body. Obviously these pieces wouldn’t fit my car so they went in the scrap bin and I got started on some new plates.



These got drawn up in SolidWorks in an hour. I had them cut at a waterjet place a few months ago. I have an extra set available if anyone is interested. You’ll need to source your own Firestone 255-1.5c air bags with bead rings instead of top and bottom plates.




The holes were offset to allow the bag to clear the strut tower (which it would have anyway) and to make space for the fill fitting.




Once these were cut, a groove was turned in the large hole top plate to accommodate an o-ring. This allowed the top plate to seal to the damper shaft while still allowing it to spin when the car turns. I don’t have a picture of it so you can just imagine:




The bottom plate was then welded to an extra pair of stock dampers with the spring seats removed and a hole tapped to accommodate the fill fitting. The top plate and bag were installed, and pair of factory spring seats and steering bearings were used along with the factory camber/caster plates.




Voila, front air struts for Volvo V/S90.



These were installed just like standard strut assemblies.






Now, the part everyone is really curious about: the back.

As you all know, lowering springs for S/V90s and similar 960s are kind of hard to get and expensive at that. Since I’m broke I found a different solution: I made my own.

Wait, WHAT! You think you can just MAKE a lowering spring? But it’s fiberglass and unicorn piss and stuff!

Yes, well that may be the case. I decided I could get away with this for several reasons:
1. The spring wouldn’t need to bear the full weight of the car. It just needs to take a portion of the load off the rear air suspension system.
2. It’s a solid piece of fiber glass. It has resin throughout so there is no great risk of splintering or uncovering dry portions. There is also no obvious complex geometry at work in this piece. It’s a brick and as such I made the assumption that I could treat it as a solid structure rather than a composite structure. I did my best to avoid creating imperfections in the surface that would act as stress raisers.
So, let’s move on to the TB procedure for making your own V/S90 lowering spring. You’ll need a belt sander, a respirator and a vice.

Remove the spring from the car (sounds like something a Haynes manual would say).
Okay, so to do this you need to pull most of the rear suspension off the car. I did this 4 times with the front of the car on the ground so it’s possible. Keep the jack handy as you’ll need to use it multiple times. Remove the brakes, trailing arms, sway bar, and the other bar at the back of the hub (the upper control arm is the only one that stays). The spring is still under tension when the suspension is completely extended so you’ll need to lift on the lower control arm with the jack to unbolt the hub from it. Then it’s a simple matter of the 10 bolts that hold the lower rear subframe to the upper rear subframe.


PS: Don't be an idiot like I was. Use jackstands, please.




Once the spring is out, clamp it in the vice, throw your respirator on, and very VERY carefully start removing material from the rear spring. This was a guess and check procedure for me.







This amount was good for a moderate static drop:





This was what I ended up having left when the car was finally low enough:





Once the spring is done, reinstall it and see how much tuck you can get:




To lift the rear of the car I had to use my imagination. I was planning on using bags from the beginning but the ‘kit’ came with cylinders. As it happes, the rear of this car has zero good mounting locations for any sort of bag. As I looked at the cylinders more and more I realized they would work perfectly.
Since a portion of the weight of the car would be carried by the weakened fiberglass spring, the single-shear trailing arm mount would be sufficient to supply this ‘helper’ lift. The cylinders would fit here in place of the factory damper.
To damp the rear suspension, I installed flow control valves in the contracting side port of the cylinder. This allowed the cylinder to work as both a damper and a spring. Problems theoretically solved.

The actual installation was a different matter. The factory damper is about 1.5 inches in diameter while the cylinder was over 3 inches so it was a tight fit.

A spare set of oem dampers gave their lives and I began mocking up mounts for the bottoms of the cylinders.







After some trial and error I finally found a design that worked. The clearances were still pretty tight:

Cylinder to Swaybar

Cylinder to LCA










With some work I was able to angle the cylinder such that the damping valve would clear all the control arms but it still was interfering with part of the frame. Taking a cue from CW who cut part of this out in his coil-over mod (albeit much less cutting), I clearance the frame for the damping valve:





The last steps were installing the compressor, valves, lines, tank, and switches. They, of course, went under the floor in the back.



This was the result:

[Kraske]

Last spring (2012) I bought a set of ML55 SUV wheels. They came with something like 285/75R18 tires and all my friends justifiably thought I was crazy.

Then I put the 215/35s on them and everyone got quiet really quick:




Since then a few minor updates have been made including:
-fresh paint in a few places
-clear turns
-city lights and minor headlight upgrades
-5000k HID low beams and fogs
-new tails
-new seats
-other stuff I'm forgetting


The air suspension was a great learning experience but I'm not really happy with it. I will be scrapping and redesigning the system in the next few months.





There are a lot of 700 series cars that are lowered. However, I'm 99% sure I have the only bagged V90 in the western hemisphere and as far as I know I have the only one in the word (come on Sweden, you've been slacking).

[Kraske]

Reserved

[rice4life]

Love the car mane!

thats one low volvo

[keeton]

Looks awesome. Nice flags.

[Randomofodication]

Gotta say that is pretty dang cool. Fibreglass spring is something I have never even heard of lol. Are you redesigning the system just to go lower?

[Kraske]

Love the car mane!

thats one low volvo

Looks awesome. Nice flags.

Thanks!

Gotta say that is pretty dang cool. Fibreglass spring is something I have never even heard of lol. Are you redesigning the system just to go lower?

Among other things, yes. I'm really just sick of the cylinders. The seals are worn out so they're loud and a little leaky, and the volume is too low so I am running accumulators to smooth out the ride in the back.

I would really like to run another pair firestone 255-1.5c bags and some different dampers which should clear up all the previous issues and may allow me a little more drop. We'll see...

[kittenpuncher]

Wow this thing is really sick, really interesting suspension set up. Good work man.

[sacrifice]

I love this. Great job with all the custom work. My first car was a 960 and sometimes I really miss it. This is one of those times haha.

[Kraske]

Wow this thing is really sick, really interesting suspension set up. Good work man.

Thanks! It's not perfect but it was my first air system and done on a shoestring budget!

I love this. Great job with all the custom work. My first car was a 960 and sometimes I really miss it. This is one of those times haha.

You know you want another one

I'm thinking about selling some of my current air components to make a little cash for the redesign. Anyone interested can find me on Turbobricks: http://forums.turbobricks.com/showthread.php?p=4530647

[SheaMoose]

Good work man!
Looks really good.

[jordy_wd]

The engineering - on the rear especially - is awesome, can't wait to see what you have in store.

[Kraske]

Good work man!
Looks really good.

The engineering - on the rear especially - is awesome, can't wait to see what you have in store.

Thanks, hopefully the next phase will look even better.

I put the Work 3-piece back on for a little while.

[JVC]

re-build those Work's with some huge lips.

I love your wagon, that pic with the 3 bagged wagons gets me all hot and bothered every time I see it!