Engine mods allowed?

[Sandman]

Outside of boltons are internal engine upgrades such as a cam allowed for STS class or is modification like this only allowed for SM?

[BlackZ29]

Maybe this will help? Sorry if the link doesn't work for ya.

http://www.scca.com/documents/Solo%20Rules/2008_Solo_Rules_2.pdf

[Sandman]

Sadly they aren't allowed. I'd be thrown into SM which I'm not ready for at all. I'll just have to wait till I can get better.