Mounts for coilovers on a C4
01-31-2008, 08:32 AM
#1
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Mounts for coilovers on a C4
Check this out...
http://www.c4guru.com/modules.php?na...=quote&p=17344
Well that's good to find out.
Nice to have a real engineering working on this stuff!
Look like if you go into coil bind before hitting the bump stops with the current setup, the mount will fail.
Sound like time for a new mount.
http://www.c4guru.com/modules.php?na...=quote&p=17344
Originally Posted by ghoffman
We are addressing both the upper front and lower rear debate.
The upper front mount distributes the load over a greater surface area so that the lilkelyhood of cracking is all but eliminated.
The lower rear is a different story. We have no idea what the OE stud is actually made of (alloy wise) but assuming it is a decent alloy steel piece, it is marginal for the loads encountered. Tom Urban measured the piece off of his '95 and I modeled it with COSMOS. The load in this model is 2200 lbs and that is just at the elastic limit (yleld). History indicates that it has not been a problem, as C4's have been running around with coil overs for years, and to do 2200 lbs, you basically have to have slam the one side of the car down at 1.5 g's. On the other hand, the other mounts, can take much more than this and argues for a new design for long term fatigue. Comments are welcome as well as sarcastic remarks!
Cheers,
Gary
The upper front mount distributes the load over a greater surface area so that the lilkelyhood of cracking is all but eliminated.
The lower rear is a different story. We have no idea what the OE stud is actually made of (alloy wise) but assuming it is a decent alloy steel piece, it is marginal for the loads encountered. Tom Urban measured the piece off of his '95 and I modeled it with COSMOS. The load in this model is 2200 lbs and that is just at the elastic limit (yleld). History indicates that it has not been a problem, as C4's have been running around with coil overs for years, and to do 2200 lbs, you basically have to have slam the one side of the car down at 1.5 g's. On the other hand, the other mounts, can take much more than this and argues for a new design for long term fatigue. Comments are welcome as well as sarcastic remarks!
Cheers,
Gary
Well that's good to find out.
Nice to have a real engineering working on this stuff!
Look like if you go into coil bind before hitting the bump stops with the current setup, the mount will fail.
Sound like time for a new mount.
01-31-2008, 09:18 AM
#2
Melting Slicks
Mine was bent before my coilover conversion. I use a grade 8 bolt and alum spacer per side. Ive seen a few other designs, but mine is the simplest from a fabrication stand point.
