SM and SSM Differences?

[BigKeyserSoze]

I am thinking of buying a Miata to run the growing SM challenge class. I see a lot of cars advertised as SM/SSM. I believe there are semi-significant differences, but do not know what they are. Can anyone direct me on what those differences are? I don't want to pay fair dollar for what I think is a SM car to find out it is SSM and then I need to spend more money to get it SM ready. Any help is appreciated.

[ZipZap]

Right off the top, an intake and exhaust. Depending on year, there could be some minor suspension differences. The biggest practical difference is that there is no limit on power in SM, given you follow the rules. In SSM, the power and torque are capped.