Helmet requirements

[George]

So I'm still not quite clear on this: What is the minimum requirment for a helmet in my open-cockpit car for autocross?

[PaulL]

It doesn't matter what type of car you have ... all the helmet requirements are the same.

4.3.1 Helmets
Helmets meeting the following standards must be worn while on
course: All helmets meeting the current or two immediately
preceding Snell Foundation standards (SA, K, or M), or SFI
standards 31.1A, 31.2A, 41.1A, or 41.2A are acceptable.

For maximum protection, helmets must fit securely and should
provide adequate peripheral vision. The chin strap must be
securely fastened. Loaner helmets should be available to vehicle
occupants not having their own.

So, get yourself either open or full face, with a Snell SA or M rating of 1995, 2000, or 2005.

Also see this thread;
http://www.rmsolo.org/forums/showthread.php?t=174

[jhadler]

Don't forget rule 4.3.3.

4.3.3 Eye Protection
Face shield, goggles or similar face protection (conventional
eyeglasses are not sufficient) shall be worn while competing in a
sports racing car, formula car, special, or in any car with less than a
stock size windshield.

-Josh2