Lowering The Front

[GT2]

I decided to try and lower my 850 using 2.5" ID coilovers. As some of you know the problem is that the stock strut body OD is too large to use standard threaded sleeves.

So... get a piece of heavy wall 2.5" exh tubing and mark it like so; then grind it to fit the prech, it dosent need to be a perfect fit.

Then slice out about 1/8", clamp the slice together and tack weld.

Slide the tacked tube over the strut, it needs to be snug. If its not, open up the slice more and try again.

Also slide the spring over the tube and make sure it fits loosely. Once the fit is good weld up the seam and grind the weld down. De-bur the inside with a die grinder. Re-check the fit.

Clamp a piece of 1/4" flat steel to a thick piece of wood and hole saw a 2.5" hole. Then without unclamping the steel from the wood hole saw over the 2.5" with a 3.5" saw. You end up with a ring. Dont worry if its a little off center. Warning- use hearing protectors, its loud!

more on next post.

[S70 R]

this looks like something BVS could do, hurry and get them on the car

[GT2]

Slide the ring down the tube as close as possible to the bottom and put one tack on bottom. Check for level and then more tacks. Finally weld all around.

Now to make the spring tops. Using 1/4" thick 6061 alum plate cut out a 3.5" disk and a 2.5" disk. Then drill out the centers the same size as the shock shaft size.

Slide the two discs over the shaft and clamp together, remove them and drill two holes.

Pop rivet them together. Then slide everything onto the shock for a test fit.

Next take the stock upper perch and trim it down to about 3.5" diam.

When cleaned up it should look like this.

More in a few

[GT2]

With the alum top placed on the "stock" perch it should fit around the bushing.

All assembled looks like this. These are 225# by 10" springs by the way.

Ok they are all installed on my car.

The good news: Car handels great, could be a little stiffer maybe.

The bad news: 1) Because the springs fit close to the "tubes" they rub a little and make noise over bumps. I guess its not a problem for a track car, or if you dont care.

2) It only lowered the front 1/4" So much for calculating. This can be fixed by using 8" springs and making spacers to slide over the tubes.

3) I'm not sure if the Bilstens are up to the task of controling those springs

4) The ride is stiff.

I'll beat it around a week and let you know if any thing develops B)

[JESSEXC]

+10 points for creativity! Nice to see others thinking outside the box!

[GT2]

+10 points for creativity! Nice to see others thinking outside the box!

Thanks! I'll try most anything once,... well maybe twice! :D

[the underlørd]

agreed! nice work dude.. PLEASE come to our next meet.. :)

[GT2]

agreed! nice work dude.. PLEASE come to our next meet..

I'll be there.

By the way Kevin your brakes have got me thinking of a future project, nothing special... we'll see

[the underlørd]

I'll be there.

By the way Kevin your brakes have got me thinking of a future project, nothing special... we'll see

hey, ask any of the guys.. anything i can do to help, I'm all in. ... lookin' forward to meetin' ya man.

[WhiteT5]

Homemade Coilovers... Turbobricks style !

I like this guy... willing to think outside the box and try something new.

[GT2]

Well I've had these "coil overs" on my car for a week now (with 10"x225# springs).

The ride seemed firmer but something dident seem right. In a medium loaded turn if I hit a small hole or small bump the strut would " bang". So I thought either the springs were going coil bound or the shock was bottoming out ( I also thought the Bilstiens were maybe junk).

Plus the spring noise is starting to get to me!

I put travel indicaters on the struts and sure enough they were bottoming out! The car wasent even very low!

Today I pulled them apart and put 325# springs on.

I also got a small motorcycle inner tube and cut a 1" wide ring and streched it around the shock body, then slid the " coilover" tube down over it. I also cut a 2" wide ring and streched it down over the spring seat bottom and let it over lap "up" the "coilover" tube. I then slid / wedged the 325# spring over the tube.

The test drive felt way better!! And NO more spring noise!! (We'll see how long that lasts)

I went on my "test" loop and hit a few corners fairly hard with no shock "bang".

I'm thinking the springs could still be a bit stiffer.

When I got back to the garage I checked the shock travel indicators and there was about 1" left befor bottoming out.

The down side is the stiffer springs raised the ride height up about 3/4"

I'm going to beat this setup around for a week, then maybe try some 8"x 375 or 400# springs.

I'll let ya know B)

[VolvoTowVehicle]

Seems strange that with 225 pound springs, which are probably almost double the OEM spring rate, you would fully compress the struts, with only 1/4" drop in the ride height. I wonder if the Bilsteins are shot. It would seem that you would have to have been bottoming out with your OEM springs as well.

[GT2]

Seems strange that with 225 pound springs, which are probably almost double the OEM spring rate, you would fully compress the struts, with only 1/4" drop in the ride height. I wonder if the Bilsteins are shot. It would seem that you would have to have been bottoming out with your OEM springs as well.

I was wondering when someone would catch that!

It was confusing me too. But I think I've figured it out.

Keep in mind that these figures are estmates.

When I was rating the stock front spring I measured it like you rate any other coilover/race spring, ie a set amount of preload and then one inch of compression.

Well with a stock spring that was about 95#(which sounded wimpy), problem is that I failed to relise that the stock spring is compressed or preloaded about 4 to 6" which gives you a starting rate of about 300 something #s (I'm going on thin memory), but the spring rate is still 95# per inch after that.

I kind of relised this after I changed to the 325# springs and the car still was med soft.

I'm going to 8" 450#s soon to lower and stiffen more!

[VolvoTowVehicle]

Something just doesn't seem quite right, but I may be missing something. I may not have seen if you posted elsewhere on measuring the front spring rates. I'll try to come up with something approximately close to what I think you're getting at:

Let's say your car is approximately 3300 pounds, and the weight distribution approximately 60/40. That yields 1980 pounds on the front of the car, and roughly 990 on each front spring. If the springs are compressed 4 inches when the car is at rest, then the spring rate is roughly 247#/in. If the spring is compressed 6 inches, the rate is 165#/in. Let's go with the 4 inch compression, since that is closer to the 300 something number you stated. I don't see how a spring can then become 95#/in after that. If it's 247, it should remain 247, and the same goes for 300, unless the spring was progressive. Keep in mind though, if the spring were progressive, the lower rate would compress first, leaving you with the higher rate as the car went through turns. Also, if the spring truly was 95#/in after that, then it should have been bottoming out even worse than the setup with the 225 pound coils.

I wonder though if there's just some other factor that I don't understand which makes my assumptions invalid. Of course, I welcome any comments and corrections if what I tried to come up with above is not correct.

[GT2]

Something just doesn't seem quite right, but I may be missing something. I may not have seen if you posted elsewhere on measuring the front spring rates. I'll try to come up with something approximately close to what I think you're getting at:

Let's say your car is approximately 3300 pounds, and the weight distribution approximately 60/40. That yields 1980 pounds on the front of the car, and roughly 990 on each front spring. If the springs are compressed 4 inches when the car is at rest, then the spring rate is roughly 247#/in. If the spring is compressed 6 inches, the rate is 165#/in. Let's go with the 4 inch compression, since that is closer to the 300 something number you stated. I don't see how a spring can then become 95#/in after that. If it's 247, it should remain 247, and the same goes for 300, unless the spring was progressive. Keep in mind though, if the spring were progressive, the lower rate would compress first, leaving you with the higher rate as the car went through turns. Also, if the spring truly was 95#/in after that, then it should have been bottoming out even worse than the setup with the 225 pound coils.

I wonder though if there's just some other factor that I don't understand which makes my assumptions invalid. Of course, I welcome any comments and corrections if what I tried to come up with above is not correct.

Ok I'll give it a go, but please understand I'm not a mathematician

Front weight is 2150#. ( See http://volvospeed.com/vs_forum/index.php?s...=corner+weights )

A stock 850 T sedan front spring is about 18" free height compressed to about 12" befor car load.

On the spring rater compressed to 12" the rate is 200# +/- a few#, (not 300 as stated befor). I'm not sure how you determined the rate by car weight? However the flaw in your example is that a spring is rated by # per inch. not over all #s. This means that 100# per " springs increase thier rate by 100# each inch compressed, ie 4" of compression = a 400# resistance.

Now this formula doesent quite work out on the stock spring (6" of compression only neted 200# ) because

of things like dead coils and the tapered top and bottoms of the stock springs and the slight progressive design.

Part of the reason I was bottoming was because the car was lowered and the way I made my upper spring seats I lost 1/2" of bump. Also I wasent bottoming "bad", but since I dont have bump stops on yet it "sounds" bad.

Not sure if this helps? Feel free to comment. :)