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Ralf
06-16-2011, 06:32 PM
I built my car with BSI's suspension set-up, which includes their camber plates with a 1" spacer welded on top of the strut tower. The shock bodies have been shortened and have Koni 8611-1257 shocks in them. When installed in the car, the springs already have tension on them, which means the shock piston can't extend any more. When the car is on the ground, I estimate that the piston is only compressed into the body about 1" or less. I only got about 5 races out of the first set and 4 for this last set. My thinking is that they are getting damaged from topping out instead of bottoming out.
Anybody had the same problem and found a solution? Right now I'm thinking of using a non-shortened strut body and placing a spacer inside of the strut body to get the same length but allowing the shock piston to be closer to the middle of the shock. Doing this, I would get about 2 1/2" before it tops out and 3" before it bottoms out.
Lowering the car even more is probably not an option, since the lower control arms are already pointing up.
What do you think?

dj10
06-16-2011, 06:40 PM
Contact Bildon.

Ralf
06-16-2011, 11:56 PM
Looking for a solution other then a complete new set-up. I like the idea of adjustability, but not the price of the KW race shocks that Bildon sells.

Dano77
06-17-2011, 09:54 AM
Can you remove the 1 inch weled spacer and effectivly lower the entire deal 1 inch down the tube. Is there enough threads on the spring perch?

Probably too diffacult to cut the spacer out,but cut off wheels are cheaper than struts.

Nodrog
06-17-2011, 11:10 AM
You need a longer strut assembly in there. The strut housing that you currently have it too short for the ride height you're at. If you can find a set of stock non-sealed struts for the VW, use a set of 8611-1259RACE inserts instead (which are longer and directly fit in the housing) and the setup will work fine.

Using the 1257 with a spacer in a stock housing will also work if the inserts that you have are all right. Just be sure that there is a hole in the center bottom of the spacer so you have access to the compression adjuster.

Gordon

T Broring
06-17-2011, 04:39 PM
Do Koni's need to run an external bump stop?

Matt93SE
06-17-2011, 05:37 PM
Do Koni's need to run an external bump stop?

All of the red/yellow Konis I've run need one. don't know about the 8611s, but I would think they do.

Ralf
06-17-2011, 05:40 PM
Gordon,
I already have new 1257's on hand, so will have to go with those. What do you feel is a safe compressed distance so that they don't "top" out? Looking at the strut bodies threads, I could cut off about 1/4" to 3/8" without having to machine more threads.

StephenB
06-17-2011, 11:21 PM
We had this issue with the Audis but it wasn't because of them topping out. It was actually the side load on the internal parts of the strut. I honestly don't remember the part that kept failing but after some research with Lee at Koni he was able to identify the exact issue. In the end we went with Bilstiens like most FWD VWs have around here in the north east. The Konis wouldn't last more than a few weekends and the Bilstiens lasted 2+ years. I will say that Koni was awesome and very helpful. If you haven't sent them directly to Koni and talked to them one on one then do so, they are (were a few years ago) very informative and helpful.

Stephen

On edit: I meant to mention that I don't think Bildon is doing anything anymore. A few friends of mine tried multiple times to contact them and to this day still have not heard back from anyone.

Lael Cleland
06-18-2011, 03:51 PM
I am firm believer in Bilstine's... The front ones on my gti were purchased in 1984 by Donald Gregory (Paul & Eric's) dad, They were on a Scirocco I ended up with that he bought new in 80... They were groupe 1s, I disassembled them this winter, cleaned them up & re-greased them, there are very hard to compress, but when you do they come shooting back! Still have gas! The thing is the side loads, these have 3-4 inches of bushing in side on a 2 inch shaft, they don't get side loads on the seal.... All i have ever heard about Konies is " they blew up"...

Ralf
06-18-2011, 05:13 PM
I'm going to put a spacer in a non-shortened strut housing and see how they hold up. If this set blows, I will buy something else.

Flyinglizard
06-20-2011, 12:04 PM
Billys, at stock length work very well. The bearing sq in ,is much higher than the Koni.
FWIW, if after install,(hanging on the lift) If the control arms point down less than 1 in. you will top out the shox and have a short life span..
MM

Nodrog
06-20-2011, 01:53 PM
Gordon,
I already have new 1257's on hand, so will have to go with those. What do you feel is a safe compressed distance so that they don't "top" out? Looking at the strut bodies threads, I could cut off about 1/4" to 3/8" without having to machine more threads.

As a rule of thumb, I go with about 0.5" above the center of stroke to be safe (including the length of the bumpstop in this measurement). For the 1257, this ends up being about 3-3.3" of rod showing at ride height.

As for the VW strut housings, don't shorten them as you don't really need to. Even with the housing at full length, you are already effectively 1" shorter with the spacer on the tower. Even an inch is almost never needed if you're trying to set the car up with level lower control arms.

If with the new setup you're hitting the bumpstop, you can cut these in about half (start at the bottom and go up). You do need to run them with the 8611s though as there are no internal bumpstops.

Gordon

Ralf
06-20-2011, 09:43 PM
Thanks for that info. The way I have it set up now is with a 1 7/8" spacer under the insert. Some left over roll bar tubing fit perfect inside the strut housing. A little bit of grinding allowed it to slip over the bottom 1/2" of the insert. Next race isn't for another month, so won't be able to tell until then how well this workes.