see ur luck one lar...i saw one guy using 400mm at grandstand...the security ask to check...then told him to keep that lens...even though the security guards dunno anything abt lens...they can still see the number is bigger or smaller than 300 mar...unless u use a 200mm or 300mm with extension lor...then maybe they will not know...the guy i saw was using a telelens for nikon with max 400mm (not prime)...the security was not very sure and he asked me as i was nearby and got pass so he sort of trust mi abit more lar...
1st day when i went in before noon (pass holders can go in earlier) my gear was checked...since my longest is 300mm i had no problem...mine was 28-300...they will see the number on ur lens lor...
oh ya...my 300mm is F6.3 and very hard for me to take decent shots at the night races...could only take without motion blur for day races...so best if your zooms are better than mine...
Don't think there was any lens restriction last year...see this thread
http://www.clubsnap.com/forums/showthread.php?t=419042