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(Post Link) post #1 of 16 Old 11-05-15 Thread Starter
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Help Lightweight alloys, just how much does it matter?

Hi guys.
As the title says:
Lightweight alloys, just how much does it matter?
It should have an impact on both mpg, and performance, but is it noticeable?

Cheers
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I've heard rumors that 1kg weight loss is 10nm of torque to the wheels. The 16v twin spark will benefit a lot from light weight wheels, because of the lack of low end power. I'm looking for light wheels but they are either ugly or too expensive. My winter rims weigh 7.3kg, my alloys weigh 8kg and I felt the difference when I put the winter wheels on, which is 700grams.
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Lighter wheels mean lower unsuprung weight and therefore handling should be better.
You would have to shave a lot more than few grams to notice the difference though, just the brake discs alone are 10kg.
Difference in mpg will not be measurable in any way, acceleration difference will be not measurable as well, not on car as heavy as the 159.
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(Post Link) post #4 of 16 Old 12-05-15 Thread Starter
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Ok, thanks for the input's, so it's not on the top 3 priority list
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Somewhere on the www is a scientific test that a motoring magazine did on fuel consumption comparing things like:-

Windows open / closed
Aircon off / on
Car empty / loaded
Tyres under / over inflated

All the things above gave very small differences (fractions of a percent.) The biggest difference was right foot. It was up to 30% or more.
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When you are trying to loose weight for racing (continuously braking, accelerating, cornering) 1kg weight saving in rotational mass is equivalent to 10kg in linear (body) weight.

In my case getting OZ Superleggeras at 6.6kg against my current GTV teledials at 11.3kg times 4 is 18.8kg That is 188kg bodywork I need to cut out for the same effect

As for get proper two piece brakes :
http://shrani.si/f/1U/12i/4v518smJ/tezediskov.jpg
The input costs are less easy to justify (it is only times 2) : 5.2kg

Last edited by Gertie; 13-05-15 at 13:54.
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I noticed a great improvement going from 18" Lenso wheels to 17" GTA teledials and everyone on here reckons that they are heavy!
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Quote:
Originally Posted by Laptop_Matt View Post
I noticed a great improvement going from 18" Lenso wheels to 17" GTA teledials and everyone on here reckons that they are heavy!
Which Lenso's did you have?
It will make a difference also bringing the weight closer to the center

Lenso Spec E Hyper Silver 18"
these 18" weigh 9kg where the 17" GTA weigh 10.4kg

Big discussion here:
https://www.alfaowner.com/Forum/tunin...h-weights.html
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Quote:
Originally Posted by Gertie View Post
Which Lenso's did you have?
It will make a difference also bringing the weight closer to the center

Lenso Spec E Hyper Silver 18"
these 18" weigh 9kg where the 17" GTA weigh 10.4kg

Big discussion here:
https://www.alfaowner.com/Forum/tunin...h-weights.html
They were Lenso Elegance 18"

I cant find them on that site, must be discontinued.

They were a bigger wheel though so more gearing needed maybe
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I tried to get light weight alloys from Rimstock (Team Dynamic) but they ended up being just as heavy and needing 50g+ of weight to balance them, absolute trash.

I'd look at the difference in tyre alloy weights for different alloy sizes and see if weight can be save by changing the size of the wheel as suggested.
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I must say that two piece discs and oz ultraleggeras made a lot difference. Steering wheel is much more comunicative, car accelerates better and going over uneven terrain is more stable.
Well it's over 20kg less of rotational mass
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Quote:
Originally Posted by alan q4+33 View Post
i must say that two piece discs and oz ultraleggeras made a lot difference. Steering wheel is much more comunicative, car accelerates better and going over uneven terrain is more stable.
Well it's over 20kg less of rotational mass
+1
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Quote:
Originally Posted by Gertie View Post
When you are trying to loose weight for racing (continuously braking, accelerating, cornering) 1kg weight saving in rotational mass is equivalent to 10kg in linear (body) weight.

In my case getting OZ Superleggeras at 6.6kg against my current GTV teledials at 11.3kg times 4 is 18.8kg That is 188kg bodywork I need to cut out for the same effect

As for get proper two piece brakes :
http://shrani.si/f/1U/12i/4v518smJ/tezediskov.jpg
The input costs are less easy to justify (it is only times 2) : 5.2kg
wow - that's quite a lot.

Where do you get light wheels from?
My car is seriously heavy (Glass roof) and i wouldn't mind lighter wheels (i don't realy like the stock 18 Inch's on the Delta).

However i am seriously limited with a 4x98 / 4x100 PDC

Alsow where did you get your 2 Pice Discs?

best regards
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Quote:
Originally Posted by Black-Sheep View Post
wow - that's quite a lot.

Where do you get light wheels from?
My car is seriously heavy (Glass roof) and i wouldn't mind lighter wheels (i don't realy like the stock 18 Inch's on the Delta).

However i am seriously limited with a 4x98 / 4x100 PDC

Alsow where did you get your 2 Pice Discs?

best regards
Well OZ Racing is an Italian company and have resellers all over the world:
Oz Racing - OZ Group
With the main importer in Germany:
Oz Racing > Händler > Importeure

Similar thing goes for AP racing discs - they are UK based, but contact them:
https://www.apracing.com/contactus.aspx
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The weight of the wheels and tyres makes a big difference on smaller engined vehicles. I've got a 120tb Giulietta, started on 16s with Bridgestone Turanzas, then 18s with Bridgeston RE002s, then back to 16s with winter tyres and now run 17" turbines with Good Year F1A2s. The first change made the car feel heavier and slower to respond on all inputs (steering, braking, accelerating) and I lost 3mpg or 9%. I didn't particularly notice it until I put the winter tyres on and it was like the car had been carrying 4 passengers and now it was empty. I did a bit of research and the 8c spider accessory wheels are heavy (13kg) and Bridgestone RE002s are really heavy (14.5kg). This was over 7kg heavier than the winter tyres (per wheel!!). Anyway by this time I decided to light (but OE) so I bought a set of 17s and Good Year F1A2. Overall combo 17kg. MPG back to original levels too with better performance. There is an article comparing wheel tyre combo sizes and its impact on a VR5 Golf in USA, but the masses aren't that different so the differences aren't great. However on a 159/Brera/Spider, which is heavy it will make a difference especially with the smaller engines.
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146 1.6TS, 156 2.0TS, 156 1.8TS, 147 1.6TS, 147 2.0TS, 159 1.9JTS, 147 1.6TS, 159 1.9JTDm, Mito 1.4, GT, Giulietta 2.0JTDm, Giulietta 1.4tb, Giulietta 1.6JTDm, Giulietta Cloverleaf, Giulietta Sport........
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Hello guys, I did not nice anything on my nissan switching from bbs 18kg wheels to light wight 15kg wheels (rim+tire).

However the car is seriously overpowered and weather conditions were not compareable....
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