Change ur rear 6x9 speaker. 

thats not my FC. my FC with RVR turbo auto is nearly that la. about 8km/L urban, 11km/L hiway..

---

Added on November 16, 2011, 11:31 am
the front speakers are only 4" ones. so sound is so-so only.
rears 6x9 speakers are good, but since it has foam material, easily koyak.
change the fronts to 6" component speakers and the rears to a better and bigger magnet speakers.
but beware that with bigger magnets (for the rear speaker) the magnets will hit the boot's batang besi mechanism.

u wanna upgrade both? depends on ur preference la. i dono what u like. u want ori or local also can? u want sound nicer only without those SPL or SQ setup?
if u want ori, Alpine Type-R 6" component around rm750, rears get those JBLs about rm350. or you may opt for ok sound from Mohawk speakers (front and rear rm600 from mudah.my)
u can search for speakers here in LYN or ZTH or mudah. here in LYN look for forumer like drexchan or howiechoo

front light perdana is so-so only.
get brighter bulb like Osram Nightbreaker or add booster.
exhaust tip senget, is individual problem la. haha. u ketuk sikit make it straight la..
my exhaust only 1 tip, no senget2.. 

yep. brand new ori Koito cost rm1200 for both side.
2nd hand may cost half that.

i'm also puzzled as to why ur car is stiff, the older the spring gets, the softer it will be.
maybe ur absorbers are out?

previously (in 2006), when my car was bog standard, it was soft and smooth as silk but cornering was a bit so-so.
so i changed to sport springs which was better handling but harsher ride.
but not satisfied, i change to adjustable suspension which is still working nicely..

---

Added on December 30, 2011, 7:56 am
if the said Koito, then it's ori but sure 2nd hand la..
i dont think anyone will sell brand new for rm3xx...

some screw must have gotten loose.
try opening up the area where the krek2 sound comes from and tighten the screws la..

kruk kruk sound when car running or parking ?