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MiniTorque*****
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Quick question... why are grooved discs used on this conversion instead of the drilled ones that Porsche use?

 

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Quick question... why are grooved discs used on this conversion instead of the drilled ones that Porsche use?

drilled discs can sometimes crack.i was told for heavy track use grooved are a safer bet. as they should not crack.i suppose it depends on how well the dics is made.i have allways gone for the grooved myself
 

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Overly excited!!
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On track even the Porsche disks have been known to crack.

Also, its not Porsche disks in this conversion. Only part that is Porsche is the actual calipers. Pads are someone else, and the other bits are GTT made.

I have also read for heavy use grooves are better than holes.
 

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are'nt the calipers technically Brembo as i think from memory Brembo make all of Porsches calipers. But yes they are porsche parts
 

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MMC Member
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are'nt the calipers technically Brembo as i think from memory Brembo make all of Porsches calipers. But yes they are porsche parts
If I remember correctly, that is right. It is not uncommon for vendors to use other vendors for parts and then stamp their name on them. In fact, the web spokes on the MINI are actually Ronal. ;)

That being said, they are probably made to Porsche specs which might or might not be tighter than Brembo specs.... Either way, they are a nice set of calipers. :cool:
 

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MiniTorque*****
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Ahh I see. I've liked the idea of the Porsche brake upgrade ever since seeing Bhozars in the flesh but each day I park next to a Boxster S and with the cross drilled discs and they just look so darn good.

The liklehood of the drilled discs cracking is surely worth the risk though for the benefit of reducing the unsprung weight on each wheel by using cross drilled discs is it not?

After all, Brembo who make the Porsche calipers also make them for Ferrari and Maserati (MC12) which both use cross drilled discs and aren't exactly light cars so if they can hammer round a track all day surely a Mini can live with cross drilled discs?

Having swapped to TD 1.2's and AP Racing BBK I'm feeling the benefit of a reduction in unsprung weight on each corner, but I'm still hankering after the asthetics of the full Porsche kit of the calipers and cross drilled discs.
 

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Overly excited!!
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I do wish the disks were lighter....

Then again, this shouldnt happen:


or
http://www.986host.com/albums/KevinC/RotorCracks.sized.jpg

I do wonder how much drilling would save, compared with grooves.

Ahh I see. I've liked the idea of the Porsche brake upgrade ever since seeing Bhozars in the flesh but each day I park next to a Boxster S and with the cross drilled discs and they just look so darn good.

The liklehood of the drilled discs cracking is surely worth the risk though for the benefit of reducing the unsprung weight on each wheel by using cross drilled discs is it not?

After all, Brembo who make the Porsche calipers also make them for Ferrari and Maserati (MC12) which both use cross drilled discs and aren't exactly light cars so if they can hammer round a track all day surely a Mini can live with cross drilled discs?

Having swapped to TD 1.2's and AP Racing BBK I'm feeling the benefit of a reduction in unsprung weight on each corner, but I'm still hankering after the asthetics of the full Porsche kit of the calipers and cross drilled discs.
 

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Hi Bhozar

the link does not work as it is only authorised for certain forums to use

Alan
Hi Alan, if you copy and paste the link into a browser window it works. Or if you click it, select the adress bar and hit enter.

Porsche relies on the following assessment of brake disc wear: "Brake disks have to be replaced (as a precaution) [if the] length of perforation hole cracks is more than 5 mm (this means that no service life reserves remain if brakes continue to be subjected to severe loads) and/or if cracks appear at the edge of the brake disc (reduction of braking comfort and of breaking strength)."

Would not dimples not do near enough the same job as drilled holes, but without the stress risers? Other disks have dimples to the wear limit, so when they are gone, its time to replace the disk.
 

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Hi Guys, holes (even cast) always crack...hence why we use grooves...much better:smile:
How about dimples Roland?

Extra cooling/less weight? Any trade off's with that?

Less weight on the wheel bearings I keep breaking would be good... then again, I broke them when I had OEM equipment hanging off them.
 

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The Power Cube
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dimples are a waste of time. you really don't save any weight (ok, perhaps a few grams!) but the gasses can't go anywhere - that's the purpose of holes and grooves. Dimples are probably the worst thing you can do to a rotor.

Grooves are the best option as they spin the gasses and compound out and also the rotors used in the GTT conversion have 90 degree edges so really provide a great edge to slice the used pad surface as opposed to a rounded edge, as seen on AP perhaps ;)

Cheers,
K.
 

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Cool CoopS
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Does anyone know if these porsche brakes will fit under 17" R99 wheels? If not whats the next best kit to go for?

Thanks Grant.
 

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Discussion Starter #59
Hi Guys, it wont fit under any of the 17" runflat rims, but will fit under most 17" aftermarket non-runflat rims.:smile:
 

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I read on eBay Porsche brakes are suitable also for Golf/Audi. What about TT (old or the new one?) brakes on the Mini?
 
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