Reconditioning Bilsteins

[tom_kauf]

EDIT: Never mind, the question I originally asked isn't important anymore. Deleted....

[Shaheenis]

Alexei this is what I could find:

"Front springs need to be progressive, but no more than 300lb. I think it may have been less than that. Front shocks need LOTS more rebound and also more slow compression. Fast bump is fine, the compression damping curve is too linear. Rear springs 400-450lb linear and the shocks just need the rebound tweaked, but are pretty good."

I have no idea whether the swift springs are progressive and do I simply ask the Bilstein reconditioner to do what is stated above?

[alexeiwoody]

Alexei this is what I could find:

"Front springs need to be progressive, but no more than 300lb. I think it may have been less than that. Front shocks need LOTS more rebound and also more slow compression. Fast bump is fine, the compression damping curve is too linear. Rear springs 400-450lb linear and the shocks just need the rebound tweaked, but are pretty good."

I have no idea whether the swift springs are progressive and do I simply ask the Bilstein reconditioner to do what is stated above?

My current front springs are non progressive...it would be nice to see what difference that would make.

Yeah, as long as the chap knows what he's doing, and has successfully done it before - I'd show him that and also ask for slightly better handling capabilities.

One of the major problems with the fronts that we found - sometimes going over a particularly shaped bump, not sharp like a pothole, but a more gradual change in road surface, the stock Bilstein just bottomed out, and hit the top hard. After changing up the slow compression, it can handle that spot without an issue.

I think it's a good idea to speak with the Bilstein reconditioner and suss out how good he is, and if he understands exactly what you're trying to achieve from the vehicle. Typically - the higher the handling "performance" of a shock, the tougher they will be on bumpy roads etc. You want to find a good compromise, and I believe this bit: " damping curve is too linear", should really help there. Also let him know about the springs you're planning to use, and if they match the application.

You'll be fine, as long as you don't do what I did and ask for "70% performance and 30% comfort...." with no mention of rebound, slow compression, digressive dampening etc. I could feel every stone, every crevice in the road for 2 months...and they would hit metal on metal every morning to work on a certain bump. I eventually had the fronts re-done again...from my mad ravings and wild descriptions, with plenty of arm waving and very colourful language, the TruTrack guys worked out what specifically the problem areas were (slow compression....too little body roll etc) and I've been very happy 2 years since!

[bigBADbenny]

Ok so it sounds like you had the same issue initially that gino had.
So crucial that the damper code is retained for future refurbs...

[Shaheenis]

BBB what do you mean by damper code? Alexei I will only proceed with re-valving if he understands that language. Even if it were conservative improvements in that department it would have to improve on stock right?

Given the rears sound more difficult to reco, I will keep them stock as it sounds like most of the improvement comes from the front anyway.

As I will end up with 2 sets of second hand billies (mine and the ones that come with the springs), how can I tell which ones are in the best condition? The rears I am referring to.

Cheers,

Tim

[tom_kauf]

BBB what do you mean by damper code? Alexei I will only proceed with re-valving if he understands that language. Even if it were conservative improvements in that department it would have to improve on stock right?

Given the rears sound more difficult to reco, I will keep them stock as it sounds like most of the improvement comes from the front anyway.

As I will end up with 2 sets of second hand billies (mine and the ones that come with the springs), how can I tell which ones are in the best condition? The rears I am referring to.

Cheers,

Tim

Regarding which ones are in best condition, get the workshop to test them. They'll have a test rig that tests the compression/rebound etc response. Quadrant only charged $25ea for that, but any half decent workshop will have a setup for testing shocks.
You could check which are visually the best (least amount of pitting or corrosion on the chrome shaft etc). That'll give you some idea of their age and km driven. But how they are internally and how they perform might be different to the condition of the exterior.

[bigBADbenny]

Re damper code I'm referring to the changes eg to slow compression that Alexei requested.

[Shaheenis]

Does that mean the service person could record such codes/specs when they do them?

[bigBADbenny]

You'd hope so

[Shaheenis]

If you want to stay with Bilstein hunt down a price on B6 shocks and fit your springs to those.

Interesting, new set from Germany or the US for ~$1000. Need to see if I can find a local retailer who can do them for a similar price and I would consider going this route.

[Emeraude]

What are the guys in Sydney charging to rebuild Billies?

[Shaheenis]

Roughly as follows (I only got a verbal):

$430 per pair to recondition
$500 per pair if bearings need to be replaced
$600 per pair to include re-valve

[Emeraude]

Cheers for that Shaheenis!

Roughly as follows (I only got a verbal):

$430 per pair to recondition
$500 per pair if bearings need to be replaced
$600 per pair to include re-valve

[Shaheenis]

Adrian, I am now considering the B6 Sport Bilstein might be a better investment if I can get a full set for around the $1000 mark landed. If you look at the Bilstein website though these are the only model that looks the same as ours so I wouldn't be surprised if the OEM ones are an older model of the B6 AFAIk exactly the same. The B8 is the one that says it is designed for lowering springs but I am sure the B6 would be fine as I am not dropping that much. When I think I could be spending ~$600 on just the fronts to have them re-valved and reconditioned, it will come down to how much I can get them for as I would prefer to avoid buying them from the US if possible. Does anyone have first hand experience with the B6 shocks?

[tom_kauf]

Yeah, B6s might perform better than factory if you're lowering your car. Because Bilstein says it is ok to lower a car a bit while still using B6s. The limit is "30mm.... Any lower and a shock absorber with a shortened stroke has to be fitted [B8s]".

I'd say our factory Bilsteins are more like the B6s than the B4s. "B4 Gas units were developed as replacement parts for standard shock absorbers. They have the same damping force as the original parts". But since our SpecBs are already an upgraded suspension, they might not count as 'standard shock absorbers'. B4s are black, whereas the B6s (and B8s) are yellow like ours.

I have B8s on my lowered 80s Mercedes and they're great! Not too firm, still comfortable but very compliant. I don't think the difference between B6s and B8s is that big - B8s are just designed with a shortened stroke for lowered cars.