Lets talk helmets.

What is a good helmet for track days.
Lots of helmets it seems and all motorcycle helmets meet AS1698.
I am more familiar with the snell standards the US has.

So does this mean you can go and buy a $45.00 a helmet from Ebay like this and use it for track events and is the AS1698 good enough for track days.
http://cgi.ebay.com.au/FULL-FACE-MOTORCYCLE-HELMET-ADULT-Med-AS1698-PL-BLACK_W0QQitemZ230286661648QQihZ013QQcategoryZ3207 8QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

It is my head and I want to keep it.

Snell is not US. Snell is internation.

Bell, Arai, Sparco.... Simpson?

It is your pick. There is not much difference between SA2000 (snell) or SA2005 standards.

EDIT: oh. Better have a light weight helmet and be sure to try it on in your car. There is not much room unless you are 5"1.

EDIT: you ticked my spending itch.... now I am looking at simpsons websites :hahano:

As long as helmets meet AS1698 they will be OK.Be wary of second hand helmets unless you know their history.Some people drop helmets on the ground on a regular basis.Not good.
There are many very reasonably priced bike helmets on the market of very good quality[I have one]
The main difference between a bike helmet and a motorsport helmet is that a lot of the motorsport ones have a Nomex or other type of flame retardant lining.
The main thing to do is take your time and find one that's comfortable and correctly fitting.
It's your head so make sure it fits snugly,without any sideways movement when done up.
Cheers
Len

And Taka's right about headroom.

I'm no giant and I only just fit in mine with a helmet on and the upright seating position most instructors will recommend to you (e.g. you should be able to rest your wrists on the top of the wheel).

Dave is correct in sitting position.

If you are vertically able, drop seat with a low racing seat. Mine now just clear hehe.

Being 6'3" tall I only fit in the car when wearing a helmet with the seat right back and tilted slightly - not ideal but I have learned to live with it.

The times I have wished Mazda had put in a telescopic steering wheel..........