Penske Spec Miata Coilover System

In 2019 the SCCA altered the rules for Spec Miata to accommodate a new shock package. After extensive testing, Penske was chosen to build a brand new shock created just for Spec Miata. These shocks are a fairly big departure from the Bilsteins we still love and use on our cars, but if you are planning to compete in National level competition, this is the spec shock and what is required to be used. If you're sticking with regional only racing, you'll want to check out the old tried and true Bilstein SM Coilover kits we also offer.

With the shocks being so different from the Bilsteins, the only things that can be carried over from your Bilstein setup is the springs, coilover sleeves, and spring isolators. The Penskes have a special machined top mount that requires the OEM shock hats to be machined larger to accommodate the new top mount. This is extremely hard to do and will require a professional machine shop, or a very skilled person operating a drill press, with a very large bit. This is a big reason we only offer these as fully assembled, because it's not something the garage-based enthusiast can accomplish as easily as the Bilstein SM coilovers.

There is also a choice between "threaded body" (version 2) and "non-threaded body" (version 1) shocks. The reasoning for this is because it was found that the Eibach springs were rubbing on the coilover sleeves on the version 1 shocks that reused the slip-on coilover sleeves of the Bilstein kits. Penske created a revision (version 2) that has built in threads on the shock body and a special locking collar/spring perch system. This was meant to cure the rubbing issue, but we hear it is still an issue. While the version 2 shocks are nicer in appearance and "racy'er" looking, the version 1 shocks are more affordable by about $250 in the end, and it's said that the version 2 shocks still have the spring rubbing issue. You be the judge!