SM GTS brake discs

jasst

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2,313
Hats off to you guys, this forum is incredible with the effort that people go to, to make owning these cars slightly less expensive.:urock::clapps::clapps::clapps: :thumb3::thumb3::thumb3:
 
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safrane

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16,748
Good to read the progress being made.

Will definitely sweeten the ownership experience.
 

midlifecrisis

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16,102
A reduction in unsprung and rotating weight also makes it easier to turn. Well it does on a motorbike, as the wheels make up a high percentage of the vehicle's overall weight. It would be similar for a car.
 

Gazcw

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Messages
7,699
It looks like it, yes. I think there are a few variations on the rear discs which we need to look into.
Excellent.. I cannot even remember what rears look like.. should take more notice!
 

conaero

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34,593
Thought the rears are the same on all models of GT and QP GTS. Not sure about the 4.2 QP
 

GeoffCapes

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14,000
If you went for option 3, would you use the same sized pads as original?
Or would you need larger ones?

Excuse my ignorance, but if it's the same size, how would there be any improvement in braking?
 

conaero

Forum Owner
Messages
34,593
If you went for option 3, would you use the same sized pads as original?
Or would you need larger ones?

Excuse my ignorance, but if it's the same size, how would there be any improvement in braking?

Yes, the calliper will be the same, just moved outwards and thus the disc will be spinning faster so more friction and thus more stopping power.
 

GeoffCapes

Member
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14,000
Yes, the calliper will be the same, just moved outwards and thus the disc will be spinning faster so more friction and thus more stopping power.

Surely the disc spins at the wheel speed? I'm struggling to understand how braking will be improved.
Perhaps I need to buy Zep a beer?
 

JonW

Member
Messages
3,259
Surely the disc spins at the wheel speed? I'm struggling to understand how braking will be improved.
Perhaps I need to buy Zep a beer?

Imagine a circle. The point at the outside spins a lot quicker than a point right near the centre.... by moving the pads outwards, it increases the speed at which the surface under the pad is moving ...
 

CatmanV2

Member
Messages
48,547
Surely the disc spins at the wheel speed? I'm struggling to understand how braking will be improved.
Perhaps I need to buy Zep a beer?

If I recall the terms correctly, the rotational velocity (think RMP) is the same, but the *linear* velocity (think how far a point on the edge of the disc rotates in a second) is higher. Which gives you a greater breaking effect.

If you're old enough..... think of a 7" 45 and a 12" 45. If you focus on the edge of the record, the 12" is going past faster than the 7"

That may help. Or you need to buy Zep a beer :D

C
 

GeoffCapes

Member
Messages
14,000
Have Googled and read a bit more on this, so I think I get it.

Would you then have greater pad wear or need harder pads?
 

GeoffCapes

Member
Messages
14,000
Also, would great braking have any effect on the abs? Or is this activated by a wheel speed sensor?
 

CatmanV2

Member
Messages
48,547
Have Googled and read a bit more on this, so I think I get it.

Would you then have greater pad wear or need harder pads?

I *think* you'll only wear your pads faster if you break faster, after all the first law of thermodynamics still applies. You will be able to brake harder (i.e. slow down faster) than with the original set up, though. And that *will* wear your pads faster.

C