Shocks

[maupineda]

B6 make the ride height higher, end.

Reason is the gas pressure, they typically have 40-60lb force of gas pressure, making the overall rate higher, so the car will sit higher.

Let’s assume the spring is 200lb/in, if you add the shock gas force, the same car weight will make the suspension travel less.

With time they settle, as some of that gas leaked away. My car is now lower compared to what it was 20k kms ago. My car has lost 7mm, which is noticeable to the eye.

I have H&R coils which are based on Bilstein mono tubes. I had set the height at factor (607mm), now my car is 600.

[plenty]

It's a while ago now, but I have dug out this old picture I took when I fitted them and was having my discussions with Bilstein; it looks like 365mm from the centre to the arch. I'm not sure what OEM is, but I bet its not 375mm!

That is indeed high. I'd have expected 340-350mm based on Eibach's claim of a 10mm drop at the rear. If it was taken shortly after fitting, I'd be interested in what it is today, after having had time to settle.

Reason is the gas pressure, they typically have 40-60lb force of gas pressure, making the overall rate higher, so the car will sit higher.

Surely that only makes sense if B6 gas pressure is 40-60 lbs higher than OEM dampers, which seems unlikely.

It does however nicely explain why a car on new dampers rides higher than on worn ones which have lost most of their gas pressure.

[maupineda]

Reason is the gas pressure, they typically have 40-60lb force of gas pressure, making the overall rate higher, so the car will sit higher.

Surely that only makes sense if B6 gas pressure is 40-60 lbs higher than OEM dampers, which seems unlikely.

It does however nicely explain why a car on new dampers rides higher than on worn ones which have lost most of their gas pressure.

You are missing the fact the architecture of the OEM and Bilstein are different, and typically the OEM gas pressure is much lower, around the 20lb. but that is not the main factor, the mono shock gas chamber is in series, stacking the gas and oil chambers, on the twin tube, the gas is on the outer tube, so the impact of it in the "spring rate" is much lesser, that is why twin tube dampers tend to be more compliant.

[plenty]

You could well be correct. To be convinced I'd want to see corrobation from Bilstein, or like-for-like comparisons of ride height from someone who's tried different and brand-new dampers with the same springs.

[taz1966]

Thanks for all the replies guys.
I can safely say that my car with the new Eibach springs defiantly runs lower than shaunKC's car.
for me i really want to retain the very slightly lowered look.
Not sure what to do know.


Sean

[taz1966]

B6 make the ride height higher, end.

Reason is the gas pressure, they typically have 40-60lb force of gas pressure, making the overall rate higher, so the car will sit higher.

Let’s assume the spring is 200lb/in, if you add the shock gas force, the same car weight will make the suspension travel less.

With time they settle, as some of that gas leaked away. My car is now lower compared to what it was 20k kms ago. My car has lost 7mm, which is noticeable to the eye.

I have H&R coils which are based on Bilstein mono tubes. I had set the height at factor (607mm), now my car is 600.

B6 make the ride height higher, end.

Reason is the gas pressure, they typically have 40-60lb force of gas pressure, making the overall rate higher, so the car will sit higher.

Let’s assume the spring is 200lb/in, if you add the shock gas force, the same car weight will make the suspension travel less.

With time they settle, as some of that gas leaked away. My car is now lower compared to what it was 20k kms ago. My car has lost 7mm, which is noticeable to the eye.

I have H&R coils which are based on Bilstein mono tubes. I had set the height at factor (607mm), now my car is 600.

What do you think of your H&R Coil overs.

[ShaunKC]

That is indeed high. I'd have expected 340-350mm based on Eibach's claim of a 10mm drop at the rear. If it was taken shortly after fitting, I'd be interested in what it is today, after having had time to settle.

Well that was interesting, I have just done the measurement again, and the height hasn’t changed at all. I think they went on in June, so I guess that does prove that what Bilstein said, that they won’t settle was correct. With their measurements there was a tolerance of course and mine was at the top of that tolerance, but then again all the rubbers, mounts etc. had been replaced so really as close to new as possible. Anyway a picture attached, it was from the centre of the wheel to the highest part of the arch. It’s not that clear on the picture because my wife was/is/has losing patience with me over the car height the measurement was 365mm

[Mr Tidy]

What do you think of your H&R Coil overs.

I have H & R coil-overs and if you find the Eibachs crashy you really don't want H & R coil-overs!

Earlier this year I got a ride in a 20K mile MC on stock suspension and the ride felt like a magic carpet compared to my car.

I have no experience of the Eibachs, but have met a couple of M owners who found them so stiff they took them off again!

It seems to be a bit of a minefield, and probably depends a lot on your personal preference as well as how you plan to use your car.

On a really good road surface my H & Rs are fantastic, but potholes tend to be the order of the day in most places.

[taz1966]

What do you think of your H&R Coil overs.

I have H & R coil-overs and if you find the Eibachs crashy you really don't want H & R coil-overs!

Earlier this year I got a ride in a 20K mile MC on stock suspension and the ride felt like a magic carpet compared to my car.

I have no experience of the Eibachs, but have met a couple of M owners who found them so stiff they took them off again!

It seems to be a bit of a minefield, and probably depends a lot on your personal preference as well as how you plan to use your car.

On a really good road surface my H & Rs are fantastic, but potholes tend to be the order of the day in most places.

Thanks for that Mr Tidy
Just like the lowered more aggressive look but not the ride.
I have lowered many of my cars but can honestly say that this is the worst car I've had for hitting the bump stops when going over pot holes.

[Mr Tidy]

Thanks for that Mr Tidy
Just like the lowered more aggressive look but not the ride.

I know what you mean.

Even set as high as the H & Rs go I've got a 0.9" drop at the front and 0.75" on the rear which looks great but doesn't handle bumps too well. But it can go a fair bit lower, which just means the springs are very short and therefore have to be much stiffer.

When I got my car with them fitted it had been slammed to the point that the floor grounded on speed bumps. I spent ages reading threads on here while I tried to work out what to do with it but I've sort of got used to them now.

And seeing as they were only a few months old it seemed a bit of a waste to take them off!

My car came with a set of Eibachs and a set of H & R lowering springs but I sold them years ago as they were fitted to 2006 OE shocks.

Good luck finding a set-up you like.

[taz1966]

Thanks for that Mr Tidy
Just like the lowered more aggressive look but not the ride.

I know what you mean.

Even set as high as the H & Rs go I've got a 0.9" drop at the front and 0.75" on the rear which looks great but doesn't handle bumps too well. But it can go a fair bit lower, which just means the springs are very short and therefore have to be much stiffer.

When I got my car with them fitted it had been slammed to the point that the floor grounded on speed bumps. I spent ages reading threads on here while I tried to work out what to do with it but I've sort of got used to them now.

And seeing as they were only a few months old it seemed a bit of a waste to take them off!

My car came with a set of Eibachs and a set of H & R lowering springs but I sold them years ago as they were fitted to 2006 OE shocks.

Good luck finding a set-up you like.

Thanks for that Mr Tidy
Just like the lowered more aggressive look but not the ride.

I know what you mean.

Even set as high as the H & Rs go I've got a 0.9" drop at the front and 0.75" on the rear which looks great but doesn't handle bumps too well. But it can go a fair bit lower, which just means the springs are very short and therefore have to be much stiffer.

When I got my car with them fitted it had been slammed to the point that the floor grounded on speed bumps. I spent ages reading threads on here while I tried to work out what to do with it but I've sort of got used to them now.

And seeing as they were only a few months old it seemed a bit of a waste to take them off!

My car came with a set of Eibachs and a set of H & R lowering springs but I sold them years ago as they were fitted to 2006 OE shocks.

Good luck finding a set-up you like.

[maupineda]

What do you think of your H&R Coil overs.

Off the box they are actually pretty bad from a ride quality stand point, other than perfect smooth roads, they rode like crap.

The can summarize the main problems with them as follows

- They are too low
- the bump stops are too long, they are under compression at ANY ride height
- The springs are too stiff
- They have too high gas pressure, so secondary ride quality is poor, and have a lot of rebound force.

Short answer is that whomever designed it, either missed very fundamental concept, or just set the car up for perfect tarmac.

I had to do a lot to make them decent, I was able to fix all issues above, except for the last item list.

- I set the car to OEM ride height, though as I said already the car settled and is now 600mm all around, which does not bother me as I am not after a lower stance or looks, but actual functional gain
- Had to cut the stops to 40-45mm (they are 70mm long!!!!!)
- fixed with a different spring set, used linear swift springs that where only 10% stiffer, spring rates I chose are 225 front, and 500 rear

With the above changes the car is not crashy anymore, and it absorbs small and medium bums much better and car is more compliant, however, the gas pressure makes them jittery (remember, you need about 60lb of force to make the shock start moving, in rough or very tiny bumps the whole car moves instead of the suspension doing the job), only in very fast compressions it can still feel crashy, but there is nothing I can do here unless I have the revalved.

The key is to ensure you set the car in a way that you don't mess the geometry (lowering the car does this) and have proper suspension travel.