This article is from the VW Performance FAQ, by with numerous contributions by Jan Vandenbrande others.
Modified Category has five classes, including three intended
primarily for open wheel race cars and two for production
based cars that have been modified beyond Prepared
allowances. In this class, the sky is the limit (almost). In
my region, we have two Datsun Z cars with Chevy V8s and a
heavily turbocharged Miata in Modified, as well as a
fiberglass GT-40 lookalike kit car. Popular Modified cars
include Formula Fords, Formula Vees, and F440s.
The SCCA publishes the Solo I and II Rules in a book that
costs about $10 (for nonmembers, less if you are a member).
The rules are updated annually and the current year's rules
are available beginning in January. The above descriptions
are general and NOT comprehensive: if you are contemplating
modifications to your car for Solo competition, I strongly
recommend that you buy a rulebook. Happy conehunting!
 
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