PART NUMBER: 61-2359
These braces reinforce the front sway bar mounting points on the front subframe. The sway bar mounting points are known to bend and/or break under cornering loads from aftermarket sway bars on cars that are running stock spring rates, because the sway bar is doing all of the work to prevent body roll. This makes these braces important for any car competing in Stock class autocross. Cars with stiffer spring rates are less likely to see failures of the sway bar mounting points on the subframe, but these reinforcements can still be added for peace of mind.
Installation Instructions can be found here:
Brian's Comments. Customers upgrading front and rear bars don't seem to need this item, stress is better distributed when both front and rear bars are upgraded and particularly when customers also have upgraded springs/coilovers with higher rates, etc. Customers in CS SCCA autocross wherein we can upgrade only the front bar, and wherein we are stuck with stock springs per the rules, DO NEED THIS or you eventually break the factory mounts at the front with the massive upgrade that is the Karcepts front bar putting a lot of focused stress on the front mounts. I am not convinced yet that customers in SCCA CS class running our Progress Front Bar need this, but it will install with our Progress front bar for those seeking insurance and running our big Progress front bar in SCCA CS.
We have seen no evidence to suggest these are needed if you are installing front AND rear sway bars, which is far better for distribution of stress loads. Thus, unless you are running SCCA CS you likely do not need these.
Just installed reinforcement kit in our new MX5 GSP in conjuction with a .120 Karcepts sway bar instructions were detailed and easy to follow. It comes with a couple of different washer sizes for a perfect fit as subframe varies from side to side. Highly recommend this product.
Dave and Heidi (2020 MX5 GSP)