Ways of reducing the weight of our cars

[the bruce]

Some ideas:


1. hood, fenders, doors, hatch

made of glass fiber or carbon fiber from Becker, Seibon and others

- 12 kg  to  - 35 kg


2. suspension

H&R, Öhlins and others make aluminium struts and dampers
racing coils are also lighter
arms and hubs from S3 or TT

 - 10 kg  to  -20 kg


3.  front bar behind bumper

Golf: made of steel; A3: made of aluminium

- 10 kg  just 1.8 kg  (so just drill and cut the stock one)


4. no DSG

- 40 kg


5. front seats

GTI 32 kg
GTI Motorsport: 22 kg
Recaro PolePosition: 12 kg

 - 40 kg / pair


6. battery

stock:  16 - 20 kg
eg Braille:  8 kg

~ - 10 kg


7. damping

I suppose not worth considering for most of us

~ - 5 kg to 10 kg


8. wheels

from 8 kg to 15 kg per piece, stock are 11 kg and 12 kg

 ~ 4 kg x 4 = 16 kg, but these are ROTATIONAL masses !!


9. tyres

between 8 kg and 12 kg per piece

save up to - 16 kg  (rotational masses as well)


10. luxory options

sunroof, leather, stereo and many gimmics more

up to - 100 kg possible


11. interior & rear seats

rear seats about 50 kg
airbags not worth considering for street use in my opinion

save 50 kg



12. brakes

~  - 5 kg


13. car jack + spare wheel

there's an aluminum jack from Audi (half the weight to steel one)
I removed the spare wheel and replaced ist by a tyrefit kit.

-  5 kg to 15 kg less


14. windows

replace side glass by Lexan or Macrolon

saves 25 kg and lowers center of gravity


 


So from 200 kg to 300 kg is possible. What's realistic just depends
on the ride comfort you still need and on your budget.

 

[marka87uk]

You know the funny thing is alot of the people that go this route and strip the cars right down to save weight when you see them or a photo of them it often makes me PMSL.
Because they never look at themselfs and think, hey i could do with loosing quite a few KG myself that may help  

I also find this quite funny!

Unless you strip a lot of the car to save a lot of weight I don't really see the benefits... say you save 15kg on an Ed30 - that's the equivalent to increasing the power by 2bhp/tonne which isn't going to make any real-world difference. Even 100kg is only going to increase power by about 13bhp/tonne.

[the bruce]

When I replace the bumper bar, the bonnet and the battery I will loose 30 kg
of weight on the front of the car. That will help cornering.

No horsepower of this world will do the same. 

[fuscobal]

marka, The bruce is right. It's not about being faster on a straight line. Loosing weight helps cornering much more than increasing power. Today I've learned something new : the bar behind the bumper and Lexan instead of the side glasses ! Bruce, can you give me more details about these ? What's the cost for both ? Do you have a part number for the bar behind the bumper ? Are you talking about all 4 side glasses ? Lexan website is down now :(

[marka87uk]

Thanks, that makes more sense! 

[the bruce]

Audi S3:  8P0 807 113 D   (80 € in Germany) - requires some modification GTI bumper/grill

There are some manufacturers cutting Lexan and bending it to the reight shape for common cars.
Even with a black frame to cover the glue and as an option with a hard laquer to prevent scratches.

(similar to the Golf's headlights)

[fuscobal]

This is the closest I've found >

Uploaded with ImageShack.us and it's with ''B'' at the end. The code for GTI one is 1K5 807 109 E. What do you need to modify on the GTI bumper/grill so that the A3/S3 side reinforcement bar fits our cars ?

[the bruce]

I didn' try it yet. I just had held the A3 bar when I had my bumper removed
(for fitting the Votex splitter).

I don't think that the GTI bumper has to be modified. But the A3/S3 bar has to.
The GTI steel bar has a bracket on top in the middle to hold the grill. I don't
know if this is really needed. I it is, it must be cut from steel bar and screwed
to the aluminum bar.
The second point is the tow ring. There are some differences as well. But still
no big problem.

[fuscobal]

Brembo GT junior kit with 330x28mm discs :

- disc > 8.8kg
- caliper with pads > 3326g (the pads only have 8mm meat as compared to my Carbotech RP2 wich have 13mm !!!)
- caliper carrier > 818g

[fuscobal]

Bruce, I have the opportunity of switching the bars with an A3. Hopefully all will go well and I will make some pics. Did you make any progress with it ?

[s3dubbin]

Do you think you could remove too much wgt? Make the car too light that traction off the line is effected? Possible?

[the bruce]

Fuscobal, unfortunately I have not.
But I'm very interested to see how it works. 

S3dubbin, NO. 

Of course there are some places where it helps more and some where it helps less.
Save weight on front and way up (roof, windows) and more on the driver's side (UK)
than on passenger side. The engine is much heavier than the gear box.

[Carrera2RS]

The front rear weight balance is very poor, I would not bother reducing any weight at the back of the car. My Pirelli came in at 918kg over the front axle, 526kg over the rear. This is with 1/2 a tank of Petrol, TD pro race alloys and TT arms. If the front mounting bar weighs a lot this could be interesting, frankly VW should have tried harder to mount the engine further back in the chassis. Coming from an E92 M3 you do understand the difference when the manufacture tries harder with basics before they look at the right bits.

I will enjoy my Pirelli and will continue to tweak, knowing it's a GTi. So far Stage 2, PSS9, TT lower arms, Neuspeed arb's, WALK, 8x18's, awaiting VWR brakes or AP Racing, Forge twintercooler (to keep the modest stage 2 on the money in all weather) for me the power is more than adequate for the shell. I thoroughly enjoy the chassis and car in the knowledge it comes from a more humble starting point, expect too much and there will be disappointment !

I keep looking at the BMW 1M....... at £40k it really ain't bad when you look at the build and bits.... 9 and 10" 19's with good tyres, M3 brakes, M3 light alloy suspension, 3.0 L twin turbo, superb diff, close ratio box, etc

[fuscobal]

What I can do on front besides the reinforcement bar is the battery. I now have the Power Cell 3000 wich weighs an impressive 27Kg > http://www.carhifishop.at/Power-Cell-3000-Batterie . I have recently found a battery that can take care decently of my audio system and weighs only 12.5Kg > Odyssey ER40 > http://www.odysseybatteries.com/batteries.htm

Problem is, my Powercell has like 95Ah and the Odyssey only 45Ah. I hope it will meet my demand as I'm not listening to my music at loud volumes or with the engine shut down !

[Hurdy]

This is the issue with the lightweight batteries, but if you take care not to run electronic systems in the car with the engine off for too long you should be fine. It is the crank amps you need to ensure match up. Try the Braille batteries. I'm sure someone on here has a 9.5kg one fitted with no side effects. Crank amps are impressive too at over 1300

http://www.braillebattery.co.uk/index.php/batteries/b3121/

Or if you want it to look sexier, you can have it with added carbon fibre

http://www.braillebattery.co.uk/index.php/batteries/b3121c/