u can take adm. in bits and prepare for iit....but its gonna affect ur cgpa ...(jyaada bhi nahi padega kyonki bits mein aake padta kaun hai...)

now if u r taking any btech degree , lower cg wont affect u much as u can coverup later(in case u dont get into iit after 1st year), but if u r taking a msc degree than it may affect the btech branch u take after 1st year...

u also hav an option of taking electronics at goa ( i also scored 325 last year and took eee at goa)....i can tell u from my experience that goa is almost equivalent to pilani and infact u hav more oppurtunities here as it is a developing campus and u are a part of that development...