so on the topic of weight reduction i thought i share my findings.
just trying to be usefull to the community.
i dont like to just take part off without replacing it with something that retains the feature of the car.

starting with sound system
1 most stock speakers are ferrite magnets/metal baskets
neodymium magnets are much lighter and smaller in size paired with a plastic composite basket will retain your speaker without losing sound quality
alot of newer cars use neodymium magnets stock already( those tiny magnets that people think are junk actually as good as stock speakers with ferrite magnets.
same goes for subwoofers. they also have ferrite magnets and composite baskets.
paper cone is still best bang for the buck.then kevlar cone.
2amplifier type
digital amplifiers are now very close in sound quality to AB class and less than half of the size and power consumption of regular amp.
theres also tripath amplifiers for those who are more familiar with electronics
digital amps allow you to use smaller gauge wire because they are more efficient.( dont expetc to power a 500w amp with a 16 gauge tho. not that far.
3
headunit most of its weight is in the CD mechanism.
mechless units are much lighter they are pretty much empty inside.

4power antenna can be replaced by onglass antenna amplified gives about same reception as regular power antenna.

5aftermarket headlight and taillight assemblies are usually lighter than stock* yes cheaper worse quality but also lighter.

6 aftermarket exhaust is less restrictive and also lighter than stock exhaust system that includes stock header.

carbon fiber hood fenders trunk lid/hatch/
removing spare tire and replacing it with a tire hole patch and a cheap autozone tire inflator ( so you dont get stuck completely with nothing)

intake system short ram is much lighter than OEM intake system

newer cars have smaller ac compressor and power steering pump is also smaller( require some customizing)


ITR ac bracket is alluminum vs steel on other models

also many people dont realize how much moisture is in your car that is soaked in carpets. seats. foam etc around the car. if you live in not so dry climate adn your car is leaking or has alot of condensation. some moisture absorbing bags would keep yur car dry and your electronics rust free.


all the above can add up to 20-50 lbs or more
when added to other weight reduction will still count.

shorter lowering springs less weight than stock. same goes for shorter shocks

aftermarket sway bar sets seem to be different design from OEM which allows them to use thinner sway bars. dont quote me on that tho
any steel or iron part that can be replaced with alluminum is probably can be made lighter than OEM iron.steel part.


one most important part.
keeping garbage out of the car.
if you think that all the autozone bullsht that you buy for your car doesnt add weight then ripp it all off and put it on a scale.

compas, cellphone holder,cellphone mat,cell phone clip. 5 different cellphone chargers, 10 brands of air fresheners or 10 air spencers, seat covers seat massagers, mirrors, JDM animals and bobble heads, half a bottle of vinyl dressing splattered everywhere.dirty underwear under your seat diapers in some cases,some fries and and loose change. and many other things. the self sustaining ecosystem around your spare tire with tools that you thought you lost 5 years ago.
collection of nightclub flyers that fall into te door.( i counted over 30 in one of the cars that we had in the shop, the owner was pretty surprised to see what came out of his doors)

i can at any given time fill up a 5-10lb bag of **** that just floats around my car.

anyone else is more than welcome to pitch in