[packinDSS]

Can someone start an official weight reduction thread? I am sure some of us have this info. It would be a great help to the community here. We use to have this on the cobra forums and it was a big help reducing the weight of our cars.

For example.

Removal of rear seats = XXlbs
stock hood = XXlbs
Carbon hood = XXlbs
Stock airbox = XXlbs
Run Flats = lbs
Type 198 wheels = lbs
etc....

Originally Posted by marcel b

here some weights (for E92):

bonnet 39.31
Rearseats 57.32
removable trunk panel rear 9.01
Floor mats 3.97
wheels+tires 231.49
brake disc front 24.03
brake caliber front 11.24
brake disc back 18.17
brake caliber back 7.72

[NMS335]

+1, Im also interested, although I think ive seen some similar threads in the past.

[stressdoc]

I thought about doing a sticky that would summarize data on weight. But there are so many different options that it is awkward.

Wheels: OEM 162 18" w/ rfts = 56.5 lbs front, 59 lbs rear. ± 1 lb. Replacement options vary from those that increase weight (esp. 19" options), to forged wheels (e.g., Volk 18" or BBS FI 19") with non-rfts (e.g., Michelin PS2) that weigh about 38 lbs front, 40 lbs rear.

Suspension: some coilovers are about 2-4 lbs lighter, Swift springs save a couple pounds, M3 parts save a few pounds.

Brakes: 2-piece alloy rotors can save a few pounds. CF rotors will save 6-8 lbs, but not yet available for the masses.

All of the above involve unsprung weight, which has much more effect on performance than weight loss in other parts of the vehicle. Another important location issue is how far from the center of the car the weight is. Reducing weight at the extremities (front, back, high up) is more important.

Other areas:

Battery: OEM 50+ lbs, Braille <20 lbs.
Exhaust: OEM >70 lbs. Many aftermarket systems are <60 lbs. Titanium is less, but $.
Seats: Power OEMs are >60 lbs. Many aftermarket seats are <25 lbs.
Stereo: It all adds up...
Junk: Manuals, tools, mats, ...
Hood & trunk lid: OEM >60 lbs, some aftermarket replacements are <30 lbs.

Options such as CA, Premium, Steptronic, etc. all add weight. The lightest stock cars are 6MT with no options.

All told there can be more than 300 lbs difference between a 6MT with above mods vs. a Step loaded.

[MuchMoore]

A mod double-post...nice

[GreenPlease]

That is funny. Two people posting the same thread within a few minutes. I'll post in this one since it seems to have more potential.

-An interesting tactic to quickly drop weight without losing functionality is to remove the passenger side seat. Good for ~50lbs. Passenger can still sit in the back seat with quite a bit of leg room to boot
-Going from the standard roof to a CF roof will drop at least 60lbs. That sunroof option is not light.
-With regards to wheels, my 19" VS7s with Continental ExtremeContact DWSs (235/35R19F, 245/35R19R) weigh in at 41 and 42 lbs respectively. I lost ~64lbs of unsprung weight by moving to this setup Granted they might have a >/= inertia relative to my 189s so I don't gain in acceleration but it makes life easier on my suspension.

It all starts to add up. Before you know it you've dropped ~200lbs from the car.

[Muffnbluff]

Weight reduction = $$$

Some things people do for reasons other than weight help such as wheels/tires and exhaust. But quality lightweight wheels are expensive.

Anyone that lives in colder climates may want to think twice before splurging for that braille race battery. If I had any kind of premium sound or navigation, etc, I wouldn't mess with a lightweight battery.

Getting a carbon fiber hood is probably the worst $/lb weight reduction as most modern performance cars have aluminum hoods which are often lighter than carbon fiber hoods.

Seats are definitely something you can save a ton of weight on in just about any car. Race seats weigh a fraction of what our big, comfy, adjustable leather seats weigh.

[GreenPlease]

^
+1 regarding $. HP is cheap on this car. Weight is never cheap. Seats are a great mod, IMO, because they're something you always touch and therefore always appreciate (if they are good).

[marcel b]

why don't you check the ETK http://de.bmwfans.info/parts/catalog/
all weights are mentioned of the original parts, very easy to calculate the impact of removing / replacing parts

[BobVader]

Girlfriend vs You for driving.

me 212lbs, my girlfriend 125lbs. I save 87lbs ...but broke my clutch...

[MuchMoore]

Originally Posted by marcel b

why don't you check the ETK http://de.bmwfans.info/parts/catalog/
all weights are mentioned of the original parts, very easy to calculate the impact of removing / replacing parts

Wow, that is a great resource thanks! The RealOEM site is great, but doesn't list weights of various items.

Cheers!

[JoosyJoos]

I'd be curious to know what the rear seats on the e92 weight. I've kinda browsed around for a DIY to remove them but haven't found one. I just wanna save some weight for autoxes.

[kyleb350]

It felt like more than 10-15lbs putting an aftermarket exhaust on. That rear section of the OEM exhaust is heavy as hell! The difference has got to be at least 20-30 lbs.

Forged wheels plus non-runflats = at least 10lbs per corner.

[marcel b]

Originally Posted by MuchMoore

Wow, that is a great resource thanks! The RealOEM site is great, but doesn't list weights of various items.

Cheers!

pleasure. spent hours on that site myself and ended up with a large spreadsheet

cheers

[marcel b]

Originally Posted by JoosyJoos

I'd be curious to know what the rear seats on the e92 weight. I've kinda browsed around for a DIY to remove them but haven't found one. I just wanna save some weight for autoxes.

see my posted link. all the weights there... isn't that much as I expected

[GreenPlease]

why don't you check the ETK http://de.bmwfans.info/parts/catalog/
all weights are mentioned of the original parts, very easy to calculate the impact of removing / replacing parts

Great resource! Thanks dude!

[Turbo>NA]

Not worth doing unless your a baller

Every 100lbs you shave off, it makes your car .1 seconds faster.

Do the math, you would have to take almost 900lbs off your car to make it 1 second quicker. lol

Even if you get an exhaust, brakes, tires, cf parts, racing seats, rear seat delete, 900lbs is still far away.

[Muffnbluff]

Originally Posted by Turbo>NA

Not worth doing unless your a baller

Every 100lbs you shave off, it makes your car .1 seconds faster.

Do the math, you would have to take almost 900lbs off your car to make it 1 second quicker. lol

Even if you get an exhaust, brakes, tires, cf parts, racing seats, rear seat delete, 900lbs is still far away.

Weight reduction doesn't just make you go fast in a straight line, it improves your handling and your braking as well. Not everything is about a drag race.

[GreenPlease]

^
Yep. That's why I'm such a big advocate of lightweighting. As it is, we can't fully use our stock motors (legally) on the street where we do 99% of our driving. I don't see "G-Limits" on on ramps, turns etc. though Not to mention less weight improves ride quality.

[Easternedge]

Wheels & Exhaust are the easiest!

Dinan mufflers weigh Like 40lbs together MAX, with the clamps!

RFT= Absolute solid pieces of chit!!

[Turbo>NA]

Originally Posted by Muffnbluff

Weight reduction doesn't just make you go fast in a straight line, it improves your handling and your braking as well. Not everything is about a drag race.

Unerstood, but once you do that and take that route the car becomes "another," car. It performes differently

For someone who doesnt have practice can lose control of the car because the weight balance is off. Unlike before with its regular weight. Get me?

Like, ppl with S2k's and Sti's that are light weight with bigger turbos making serious power have a higher chance of losing control of their car due to weight ratio to hp/trq.

For example, my friends e46 m3 weighs about 3,100 lbs if not lighter, His car is supercharged, he tells me I cant get traction, turning is harder because the car is more fragile and light weight. I mean weight reduction is some what dangerous but fun to play with.

I think the most improvement you see with weight reduction is at the drag race.

[GreenPlease]

^
Maybe you mean to say that its harder to control at the limit? Lighter vehicle = better traction and higher limits all else being equal.

[hotrod182]

Originally Posted by GreenPlease

^
Maybe you mean to say that its harder to control at the limit? Lighter vehicle = better traction and higher limits all else being equal.

Sometimes better handling cars have more serious accidents. This is because when the drivers lose control, it is often at higher speeds.