Need Help Destroyed another shock

[Bow Tie 67]

So I noticed oil on the driver side frame after getting home from Motorstate, it turns out it is shock oil.







This is the second shock I have had an issue with. My subframe has no bumpstops, prior to my swaybar upgrade I bottomed one out and it leaked, now this.

The shocks have been on the car since summer of 09 with several track days and no incident. So here are some pics of the suspension and I'm wondering what loads will be placed on the upper and lower a-arms when contacting a stop. I'm running 600 lb springs and still had 3/4" compression available on both shocks. The car was setup right at the midway point of shock travel. Total travel is 4 1/4" with a 1/4" o-ring as a shock extension stop. So the effective shock travel is 4" at the limits.

I'm getting tired of shock damage as it gets expensive, not to mention down time on the car.

I'm thinking of adding a bump-stop to the bottom of the frame-rail for compression, and fabricating a bracket with the bump-stop contacting the upper a-arm adjustment turn-buckle. My concern is the loads that may be placed on the control arms when contacting a stop. I think having the upper bump-stop contact the a-arm at the cross-shaft would be better, but then I get into packaging problems with the sway-bar arm's travel and providing enough support for the stops mount. Help .................



Thoughts?

[silver69camaro]

Bumpstops would be my first step. I don't know what kind of internal stops those shocks have, but it's unusual for the top to push out like that - they are well built shocks. What's odd though, is that would only push out (that I know of) with excessive rebound, not compression.

On a side view, are those shocks mounted at an angle? I'm wondering if there is excessive side loads and working the top cap loose.

[Bow Tie 67]

Bumpstops would be my first step. I don't know what kind of internal stops those shocks have, but it's unusual for the top to push out like that - they are well built shocks. What's odd though, is that would only push out (that I know of) with excessive rebound, not compression.

On a side view, are those shocks mounted at an angle? I'm wondering if there is excessive side loads and working the top cap loose.

Excessive rebound as in shock adjustment or lifting a tire?

The shocks appear to be mounted vertical.

[dontlifttoshift]

Did it push out or just unthread itself?

Actually if it was bottoming out it wouldn't have anything to do with the top plate would it? In order for the top plate to come off it would have to pull out....or just unthread it self.

[Bow Tie 67]

I had one bottom out before and it damaged the closer nut and was leaking. The threads are slightly damaged but they were not ripped out. So its looking like the nut loosened up first.

[dhutton]

I had one fail like that but it failed due to a sudden drop in the road, not compression. I think these shocks do not like a lot of preload on the spring. At least that is my thinking but I have no analysis to support it.

[silver69camaro]

Excessive rebound as in shock adjustment or lifting a tire?

Yeah, but to be honest I've only seen that in super high spring rate applications where the shock just wasn't suitable for the job. Most if not all aftmarket shocks have some sort of rebound stop that should keep that from pulling out. But, if the theads appear to be OK, maybe it just walked out? Never seen that before, but anything is possible...

[silver69camaro]

I had one fail like that but it failed due to a sudden drop in the road, not compression. I think these shocks do not like a lot of preload on the spring. At least that is my thinking but I have no analysis to support it.

What brand was it?

[dhutton]

What brand was it?

Sorry, same brand, Varishock. To be fair they took both of them back and rebuilt them for me no charge. I have had no issues since changing spring rate to require less preload.

[Bow Tie 67]

Setup, 600 lb spring, ( recommended rate per manufacturer for application / use ) Vari-shock double adjustable, ride height set at mid travel, no major suspension bumps or dips, shock was set at 10/16 rebound and 8/16 compression. ( clicks ) Would 600 lbs be considered excessive, I would not think so. The car weighs 3185 wet without driver.

[Bow Tie 67]

Earlier in the year I took a good look at the new ridetech coil over shocks and really liked what they have to offer. As your average working stiff I could not justify the cost of changing a component that's doing its job, so it was only a passing thought. Well things change, and now I have a decision to make, have mine rebuilt or try another brand. I made a call to ridetech and my mind was made up, I decided to try their new coil-overs.

I installed my new single adjustable shocks yesterday and took a short ride. So far so good, the car feels more responsive, the big test will be at the Heidts challenge in two weeks. I will leave feedback once the event is over.

In the mean time here are some pics. Due to the difference in shock design, the Ridetech shocks were more difficult to install. For one they actually have a nitrogen charge, so the shock wont stay collapsed and the mount bolt center line to shock body is a shorter distance. At first I thought I might have to grind for clearance on the lower control arm, but soon found if I pushed the suspension down as far as it will go I could set the shocks in and install the bolts. I double checked full suspension travel without the coils to make sure no binding would occur. SCORE !! there is enough clearance.

I'm still working on some suspension stops, but have faith in these shocks as they have real bumpers vs a 1/4" o-ring!!

clearance to lower control arm



Installed pic

[monteboy84]

I'm still working on some suspension stops, but have faith in these shocks as they have real bumpers vs a 1/4" o-ring!!

That O-ring isn't a bump-stop, it's a travel indicator.

-matt

[Bow Tie 67]

That O-ring isn't a bump-stop, it's a travel indicator.

-matt

No Sheet!!!! ............. not in a good mood today

[bret]

Just so you guys know...the ridetech shocks have an internal extension bumpstop. I'll see if I can dig up an image to post of that stop. The compression bumpstop is the large rubber washer visible around the piston rod, and doubles as the travel indicator.
REALLY glad to see that you have checked everything out for clearance through the entire suspension travel...VERY important.
Looking forward to your performance evaluation...I will be at the Heidt's event...we'll chat then. Thanks for trying our stuff out!

[monteboy84]

No Sheet!!!! ............. not in a good mood today

My bad, wasn't sure if you were serious or not. Turns out sarcasm is hard to convey through text

-matt

[darren@ridetech]

I you look closely in this video, you can see the extension bumper at the bottom of the rod guide.
http://www.ridetech.com/store/suspen...ms/coil-overs/

[JRouche]

It looks like the cap backed out and un-threaded itself. I dont see any thread damage that would be visible if the cap got pulled out.

Solly to see they didnt use any thread locking compound to lock the cap in place. Aluminum threads dont have the ability to torque the fitting down tight enough like steel to get a "stretch" and decent holding ability. Unfortunately it looks like they rely on the pressure from an O-ring or something the keep the cap in place. Not good!!! A simple application of some decent thread locker compound (I would use loctite blue, dont use red, it will kill the threads if you need to remove the cap) would have kept that cap from coming off. JR

[Bow Tie 67]

Heidts challenge results

5th auto-cross
7th road course

5th over-all event

I'm going to say, I LOVE the new front shocks.

I have never been very good at the autocross, now the car transitions much better allowing me to learn to drive the car and not fight it.

On the road course she was very predictable and had no problem handling the large rumble strips when I was to wide or pinched a corner.

Street manners are vastly improved, the new shocks can be dialed down and give me a more sedate ride.

All in all I'm very happy and dont believe I need to worry about bump-stops. I have set the compression bumpers down on several occasions and only had them show contact once ( railroad tracks ) although I did not feel any harsh compression.



Plane and simple ridetech coil overs work!!!

[wiedemab]

Nice - I'm glad to see that they worked out well for your car!

[Tony@AirRideTech]

I heard about the results from the Heidts event.... good Job Matt! Thanks for the Props and the feedback!