I think it all depends on the cop... if the exhaust is obnoxiously loud obviously you have a high chance of any cop giving you a ticket. Then you have those cops that has nothing to do or having a bad day and will give you a ticket even with the quietest aftermarket exhaust system. Also depends on how you drive...some guys are heavier on gas then others. I noticed on mine with HKS non-resonated mid pipe and HKS Legamax cat back it only gets really loud around mid rpm range and up. I don't know how LC cops are sensitive to exhaust but from what I remember it wasn't too bad. Maybe things have changed since the last time I lived there.
I grew up in LC a long time ago... went to Paradise Canyon elementary and LCHS JHS and HS. Lived off of Gould and Knight Way... Went up and down the crest countless number of times. Try not to take the R35 up there...just keep it at the track and be safe.