Bilstein HDs and lowering springs

John In Valdosta · Post by **John In Valdosta** » Mar 10, 2005 10:40 AM

After reading through several pages on the Archives (here and roadfly) I found alot of post where people were using Bilstein HDs and lowering springs. Many of these post were from a few years ago and I was wondering if anyone has seen any adverse affects.

I have always heard that runnng HDs with lowering springs would cause premature failure in the shock. Is this a fact or just another lie told to small children.

lino · Post by **lino** » Mar 10, 2005 10:50 AM

I know someone who has Blstein HD and Eibach on his Mercedes W124 and he swears that it's more comfortable than the sport springs since they are shorter and that he is very happy with the setup. He has had it for quite some time. I think as long as the springs are a modest drop (1"- 1.25") than it's ok.

C.R. Krieger · Post by **C.R. Krieger** » Mar 10, 2005 10:54 AM

John In Valdosta wrote:After reading through several pages on the Archives (here and roadfly) I found alot of post where people were using Bilstein HDs and lowering springs. Many of these post were from a few years ago and I was wondering if anyone has seen any adverse affects.

None whatsoever, using Bilstein HDs with a set of Eibachs advertised to lower the front ~1/2 inch and the rear ~3/4 inch.

I have always heard that runnng HDs with lowering springs would cause premature failure in the shock. Is this a fact or just another lie told to small children.

I'm going with the 'old wives' tale' theory.

Craig -535i- Seattle · Post by **Craig -535i- Seattle** » Mar 10, 2005 11:45 AM

The HDs are longer, you can bottom out more. I suppose it depends on the springs you pick.

I HATE HATE HATE mine with the POS BavAuto springs I have. The car bottoms out constantly unless I am careful about bumps at speed. They are the next on my list of things to fix on the car.

Note that the HDs and Sports are the same stiffness, they just are different lengths.

Edit: I've got an E34 so YMMV.

[Edit by Craig -535i- Seattle on [TIME]1110473146[/TIME]]

SmokinDav · Post by **SmokinDav** » Mar 10, 2005 3:12 PM

Which begs the question that has been asked a thousand times I'm sure, but on the old forum.

What are the best springs (brand, model and spring rate) for autox and track duty? Where is the cheapest place to buy them?

Craig -535i- Seattle · Post by **Craig -535i- Seattle** » Mar 11, 2005 1:38 AM

Hey Dave-

These aren't Mustangs so rates are never discussed unfortunately. It's all a big secret.

I had good luck with H&R on my Cobra, that's probably what I'll be getting for the 535i as well. As for which ones, I'm not sure yet.

BDK · Post by **BDK** » Mar 11, 2005 8:16 AM

If you run the HDs, don't pick the BavAuto springs, they lower the car too much for HDs and thus they run on the Bumpstops all the time...

I HATE HATE HATE mine with the POS BavAuto springs I have. The car bottoms out constantly unless I am careful about bumps at speed. They are the next on my list of things to fix on the car.

It is not the springs, its the length of the HD's and the fact they are running on the bump stops....BavAuto no longer list HD's as being compatible with their springs, they now suggest the sports....

Craig -535i- Seattle · Post by **Craig -535i- Seattle** » Mar 11, 2005 11:57 AM

[QUOTE="BNC"]It is not the springs, its the length of the HD's and the fact they are running on the bump stops....BavAuto no longer list HD's as being compatible with their springs, they now suggest the sports....[/QUOTE]

Well, IMO these springs are way too soft for how short they are. There is a lot of body roll, but I drive on the track occasionally so probably bias my opinion towards that more than most would.

If they were at their current rate but about a half inch longer I still wouldn't like them, despite not bottoming out.

dasMafia · Post by **dasMafia** » Mar 11, 2005 12:26 PM

IIRC the sports are just a few dollars more than the HDs and come with the same warranty, so there really is not reason not to run the sports if you're going to lower the car.

as for which springs... per my recollection, Racting Dynamics and Suspension Techniques tend to have the best rates all-around. they are a long way from "soft" but eh, that's not really the point, is it?

the only thing stopping me is I only want to pull it all apart once, and want to go BBK, 16s and springs/shocks all at once.

I've got the money for springs/shocks, but 16s and brakes are still in the works...

shifty · Post by **shifty** » Mar 11, 2005 1:38 PM

I heard the problem with running the standard-length Bilsteins (HDs, Tourings, Comforts, etc) on lowering springs is that you'll never use the full ability of the shock since it will always be somewhat compressed.

I've also heard that the problelm on the Bilstein Sports is not the shorter shock body but the HUGE bump stop. If you cut the bump stop down (say, in half), you'll have half the problems you had before.

I'm seriously thinking about going back to Bav Autos and Bilstein Sports for my 528e. I think the two main problems I had were because of a bad shock, a bad shock mount, and huge bump stops.

C.R. Krieger · Post by **C.R. Krieger** » Mar 11, 2005 1:46 PM

[QUOTE="Shifty"]I heard the problem with running the standard-length Bilsteins (HDs, Tourings, Comforts, etc) on lowering springs is that you'll never use the full ability of the shock since it will always be somewhat compressed.[/QUOTE]

Where the hell are you getting this shit? The works of a shock are in the valving, not the amount of 'head space' it has! :@ It doesn't matter where in its stroke it starts out (unless it's a gas-charged shock, which would start out a bit more energetically, but otherwise perform the same throughout its stroke). It should dampen movement by the same amount whether it is nearly completely extended or nearly completely compressed. It is not a spring!

shifty · Post by **shifty** » Mar 11, 2005 2:31 PM

I know the difference between springs and shocks.

What I was saying is that you're not using the full advantage of the longer shock travel by using the HD with a lowering spring. There's a certain part of its travel that you'll never use, because the shock is compressed -- a spring term, I know, but you know what I mean.

My point is that the Sport is pretty much the same stiffness as an HD yet it differs in the length of the shock body. The Sport was made for lowering for a reason. Why run the HD when you have a similar shock made by the same company for the spring you want to run? Cut the bump stop on the Sport, and you're good to go.

Velocewest · Post by **Velocewest** » Mar 11, 2005 4:07 PM

How are you going to cut the bump stop? Bilstein bump stops are internal.

Kenny Blankenship · Post by **Kenny Blankenship** » Mar 11, 2005 7:24 PM

I can't recall where I saw it but there was a list of the aftermarket spring rates for the E28. Racing Dynamics was the stiffest, Eibach I think was towards the stiffer end, and B&G was at the softer end (of the aftermarket springs). Someone will have to refresh my memory as to where the list is located...

stuartinmn · Post by **stuartinmn** » Mar 11, 2005 7:38 PM

This is cut and pasted from the M535i.org site:

1. Stock - 166 lb/in - 0mm drop
2. M-technik, BMW - 193 lb/in - 20mm drop fr/rr
3. Dinan (Stage 1-4, #D100-0417) - ~200-220 lb/in - ~20mm drop fr/rr or 5/8ths to 3/4 in. drop (also Spring Set #D100-0442 - less expensive, for Euro M5/M635)
4. Suspension Technique (#60065)- ~200 lb/in - 20-25mm drop fr/rr
5. Bavarian Autosport - ~200 lb/in - 32mm drop or 1.25 in. drop
6. Alpina - ~200 lb/in - ~20mm drop
7. Hartge - ~220-240 lb/in - 35mm drop
8. Eibach - ~220-240 lb/in - 30mm/35mm drop, or 1.2/1.4 in. drop
9. H&R Springs - ~220-240 lb/in - 32mm drop, or 1.25 in. drop
10. Racing Dynamics - 274 lb/in - 32mm drop, or 1.25 in. drop

shifty · Post by **shifty** » Mar 12, 2005 2:30 AM

That's not completely right. The drop with the Bav Autos is without a doubt more than the drop you get with H&R springs.

BDK · Post by **BDK** » Mar 12, 2005 9:56 AM

I agree with shifty, the BavAuto Drop is closer to 2" in the front and about 1.5" in the rear, it drops the car the most that I have seen....
I think maybe Spax makes a spring that will drop it lower but can not confirm this....TCD had a set you could ask him...

In the pic I posted you can see Dukes car on H&R and mine on BavAuto and how much lower mine sits.... Todds car (his 5 not the 7 in the pic)on SPax sat 1/2" lower if remember correctly

[Edit by BNC on [TIME]1110639449[/TIME]]

[Edit by BNC on [TIME]1110639483[/TIME]]

Tjn182 · Post by **Tjn182** » Mar 12, 2005 10:21 AM

I got HDs all around w/ eibach sport springs -- It's a lower and stiffer ride for sure... yet it's not as stiff as I want. I believe my shocks are going bad and I'd rather just sell em and get something a little bit stiffer.

Monotalonawd · Post by **Monotalonawd** » Mar 12, 2005 1:32 PM

I got HDs all around w/ eibach sport springs -- It's a lower and stiffer ride for sure... yet it's not as stiff as I want. I believe my shocks are going bad and I'd rather just sell em and get something a little bit stiffer.

Are you going to sell your Eibach's?

cgraff · Post by **cgraff** » Mar 12, 2005 3:45 PM

That's not completely right. The drop with the Bav Autos is without a doubt more than the drop you get with H&R springs.

Well...Remember. Those are "official" figures I got way back when from the manufacturers or the suppliers.

The reason BavAuto springs *might* tend to drop the car so much more is due to the lower spring rate (compared to similar lowering spring rates).

Personally I believed BavAuto F-ed up when it came to their springs. You can't have it both ways (soft sprung and lowered). And it's extraordinarly difficult to get a progressive rate spring (which can solve that problem) to perform well or predictably.

For springs, you can't go wrong with H&R, Suspension Techniques, or Racing Dynamics. (Of course Dinan, BMW, Alpina, and Hartge are all great quality.)

And the HD shocks are longer than the Sports. The damping is the same. I refer you to Bilstein's website which states that information explicitely. The german one actually has a decent amount of good info (as opposed to the US site).

www.bilstein.de

-Chris

Tjn182 · Post by **Tjn182** » Mar 12, 2005 4:12 PM

I got HDs all around w/ eibach sport springs -- It's a lower and stiffer ride for sure... yet it's not as stiff as I want. I believe my shocks are going bad and I'd rather just sell em and get something a little bit stiffer.

Are you going to sell your Eibach's?

Monotalonawd wrote:

Are you going to sell your Eibach's?

Nope

The Eibachs work great! There's no way I'm gonna ditch them!

MyE28.com

MyE28.com

Bilstein HDs and lowering springs