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Rear Coilovers On a S197 Chassis

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There seems to be some misinformation going around regarding installing true coilovers on our cars. There have been thousands of coilovers installed with no failures that I know of. When using the proper bracket and installed properly the stock mounting location is plenty strong. Please post up if you've ever seen a failure first hand.
 

ArizonaBOSS

Because racecar.
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Arizona, USA
I have not seen a failure yet.
I think a lot of these "rumors" are based on assumptions about the strength of the rear shock mounting point. One thing I do know is that the FRPP brackets that are used to attach most of the coil over rears in an "eye-to-eye" style have the brackets wrap over part way into the wheel house, so some of the load is spread into the vertical part of the rear subframe itself instead of straight into the horizontal flat shock flange.

So far I think everything seems OK--but I'm not an expert.

I don't have this setup, myself, but have seen them in-person many times.

One benefit the competition (302R/S) have is that the rear downtubes for the cage land in these points so that adds extra vertical reinforcement.

There are other arguments for having the springs mounted in the factory locations such as motion ratio and effective spring rate--that's a separate discussion from durability/failure though.
 

cortexracing

Supporting Vendor
42
134
Failure of the rear upper shock mounting point of the S197 chassis is extremely unlike. We have never seen it happen and there is good reason. The upper mounting pad is tied directly into the rear unibody frame rails with steel that is quite thick. The upper pad that the OEM shock bushings bolt to approximately 0.200" thick and it is surrounded by multi-wall heavy duty vertical reinforcements on all sides. The CorteX Racing upper shock mounts have a large pad area that spreads the loads and feeds them directly into all of the vertical supports surrounding the bushing pad area. Because the shocks are nearly vertical there is essentially no side loads (horizontal). For those that are not convinced, you could always retain the OEM bump stops that are bolted to the top of the axle tube and shorten them as needed to ensure adequate bump travel. We do this on the majority of our installs mainly because it is easier on the shocks over time. If retained, the OEM bump stops would take loads from a large hit such as jumping the car instead of the shock mounts. We have spent a fair amount of time thinking this through and testing our design on daily driver and dedicated race cars of a number of years. The benefits of a much improved motion leads to better ride quality and much improved handling. Properly setup full coil-overs on an S197 are amazing and we highly recommend them for all serious enthusiasts.
 

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