Current FFR Bilstein Shock Issue!

[Jamo]

Keep this thing down to a minor roar or we'll throw water (not koolaid) all over it.

[xlr8or]

LOL

[BeanCounter]

I haven't been part of the discussion over on the FFR site because I left there due to all the problems you guys have cited several years ago. I have probably one of the oldest FFR's around, 1056. I know of only 5 or 6 that are older. It's been on the road for 11 years. I run Carrera's on my car and have had absolutely no problems in all of the years and I drive on a lot of country roads that are pretty brutal on the car. To me it doesn't matter if it's Bilstein's fault or FFR's, the responsability lies with FFR. They need to step up to the plate and save somebody's life. They can then fight it out with Bilstein.

[John McMahon]

Originally Posted by BeanCounter

To me it doesn't matter if it's Bilstein's fault or FFR's, the responsability lies with FFR. They need to step up to the plate and save somebody's life. They can then fight it out with Bilstein.

I absolutely agree with you 100%.

[Hoofa]

FFR should step up, But it's been years now. Something has to get done before someone dies. I could just picture my old girlfriend at my funeral " I told him it was stupid to build your own car, If that boob listened to me he'd still be alive."

[xlr8or]

Now wonder your nuts are broken. That was way too much rack for them to handle.

[Maricopa]

Very nice Hoof!

I am guessing Bilstein are not cooperating because they suplied the shock as requested. FFR converted it to a coilover and decided it would work at an angle

I think this is basically true. The vast majority of the shock failures have been attributed to 'bad' springs that were being sent out, supposedly after a supplier changed their specs. These springs had too many coils and on a hard bump would lock up sending all that energy right into the shaft. The other thing that was happening was the spring becoming unloaded at full droop and coming back to rest on the cup in a cockeyed position, putting large side-loads on the shaft. These are all things out of B-stein's hands and IMO they shouldn't have to answer for it.

Besides the things I mentioned above I think an underlying reason for the breakage is that the B-steins simply are too small. I don't have the buckage right now to buy the Konis but I have a friend that did and gave me his old Pro Shocks. Besides this shock being an actual coil-over rather than a conversion the shaft is .070" larger, the body larger and the spring dia larger. Why in the hell, if not simply to save money, would they have downsized the shocks?

[ENTDOC]

Hoofa, damn nice of you to step up and try to help, and if the nuts decrease the stress on the offending area of the shock it would seem wise to use them at least untill another option comes along.

The SPF coupes had a similiar problem where the front suspension broke on a few cars. All were under track conditions, however, it was still not acceptable. SPf sent out replacement parts to every owner to rectify the problem. Now that is of course a much smaller number than the FFR situation, but the point is that it was taken care of quickly and at no expense to the owners. What does that say about SPF? it says they screwed up and the owners raised hell and SPF fixed the problem before someone was hurt.

[mrmustang]

Hoofa,

It is not sideload that is breaking these shafts. Having bent enough old Bilstein shafts to prove that point back in 2006...........


Bill S.

[Hoofa]

The shafts don't bend they snap, they're very hard. The ares where they break, bends, as it's softer metal with a sharp cut into it. Repeated cycling is the enemy. Again I'm not an engineer, just a guy that couldn't afford new shocks to replace my new shocks. This is great being able to discuss this issue. This is how we'll fix this problem, with open discussion. This is after all why Al Gore invented the internet.

[Hoofa]

This is a text book break.... I just looked it up in a text book. That area is a textbook example of a fatigue break. Two beach areas, final break perpendicular to max stress. Huge stress riser. Fine grain steel is particularly susceptible to stress risers. I would guess that the tensile strength of the shaft is greater than whatever is holding the shaft in the shock body. I'm not doubting that the shock is too short, I just don't think that is the root cause of the breakage. Were the Proshock failures from being pulled apart?

[mrmustang]

Hoofa,

Your still thinking this is a lateral load or overload issue when it's not. Again most of the breakage is not of a lateral load issue. Some are due to misalignment, or incorrect installation, but not the majority of them as you have been lead to believe. Once more, FFR (both Jesper and Dave Smith) had this unbiased third party information along with pictures and in one case the broken shock(S) that was(were) analysised back in 2006.........


Bill S.

[mr bruce]

http://en.wikipedia.org/wiki/Hydrogen_embrittlement

[Hoofa]

Originally Posted by mr bruce

http://en.wikipedia.org/wiki/Hydrogen_embrittlement

If we could just channel the hydrogen away from the shock and into the engine we'd be in business! That's a win,win.

[TButtrick]

Hoofa,

Trying to understand how that nut is installed. The shaft doesn't seem to have the thread length to accept a long nut plus the rod end.

I've always felt the rod ends are being installed incorrectly by a few but not certain it could be attributed to any type of fault. I watched a fellow builder take the lock nut and ram it down on the shaft as far as it would go then take the rod end and tighten it against the lock nut. I'v been told never to bottom the lock nut like that but rather turn it CCW toward the rod end with a wrench on the rod end to snug them together.

[mrmustang]

Originally Posted by TButtrick

I've been told never to bottom the lock nut like that but rather turn it CCW toward the rod end with a wrench on the rod end to snug them together.

Who ever told you this is 100% correct, you never ever want to bottom out the rod end and the lock nut at the very bottom of the threaded shaft.



Bill S.

[Hoofa]

Originally Posted by TButtrick

Hoofa,

Trying to understand how that nut is installed. The shaft doesn't seem to have the thread length to accept a long nut plus the rod end.

The nut has a interference fit sleeve that slides over the thicker part of the shaft. It has the same amount of threads as the original Jam nut. It just isolates that super ****ty area of the shaft so the only forces it sees are tension and compression. It transfers the bending forces to an area of the shock that has a 42% greater cross sectional area and better metal. That area of the shock is built like a samurai sword. It has a tougher core with a hardened shell. And NO stress risers. Fine grain steel is very sensitive to stress risers.
I'm thinking about breaking a couple more shocks today to see how short I can make the sleeve.
Someone tell me I'm wrong so I don't waste any more time or money.

[mrmustang]

Hoofa,

I love your work and your ingenuity, but the real issue at hand is not on the compression stroke but on the extension as the shock can only extend an addition 2" before maximum travel has been achieved, thus causing the stress fractures because the shaft cannot extend further than it's maximum length vs the additional 1-1.5" of suspension travel on uneven roads or potholes allows in real world driving. Think of pull instead of push on the shaft and you'll understand where I am coming from.



Bill S.

[Hoofa]

I completely understand what your saying. But the way the shaft fractures, tells me a different story.

[mrmustang]

Originally Posted by Hoofa

I completely understand what your saying. But the way the shaft fractures, tells me a different story.

Go back and study all of the pictures again, as the last several show two different fracture signs, one from the over extension, the other from a side load. Do you not see the difference in the two different shocks?


Bill S.