996 Big Brake Kit Review
#91
You can* do weird and wacky rotor size combos but you'd need to know exactly how to stagger the pad compound to achieve a correct brake bias. Race pad manufacturers with a wide selection of compounds make it possible (I do it myself), but you have to ask yourself is it worth it on a road car.
I will take Brembo Discs and Pads all around, refresh the calipers and drive with that combination.
#93
Funny Thing....
YMMV
#94
You're pretty much spot on with all of your points. The stock calipers are retained and are secured using longer bolts. The diameter of the rotor has increased, and the caliper is further from the centre of rotation, giving it a greater mechanical advantage. However, the braking power increase this confers is modest, perhaps around 15%. (I did the calculations way back and don't have that notepad to hand, otherwise I'd give the calculation used). The bigger rotor does give a significant advantage in cooling, fending off fade for longer, and in many systems preventing it entirely. ...snip...
if you shop around for cheaper discs. Please note I haven't so far found any of the cheaper discs to give a sub-standard performance, so please don't assume that in this area paying cheap means paying twice.
if you shop around for cheaper discs. Please note I haven't so far found any of the cheaper discs to give a sub-standard performance, so please don't assume that in this area paying cheap means paying twice.
In other search I found that a 2015 Panamera S rear rotor is 350mm X 28mm. They look fairly inexpensive, ~$250 each. Would this rotor fit your circular adapter? Rotors suggested from RockAuto are "Out of Stock" and do not seem to be available any more. The problem finding a rotor is P-part nos. are just that, no description of dimensions to see what will/won't fit. Adding an 8mm spacer is not a lot - is that the thickness of the circular adapter? Has anyone found a cross-drilled vented rotor similar to the standard S/Turbo rotors?
Are different wheel bolts needed or replaced with wheel studs (as in the air-cooled P cars)?
Can you post a photo of your Big Brake Kit (BBK) ? Confused. Maybe TexSquirril has answers?
OK, I JUST NOW "found" Martin Hill BBK on eBay. Good grief, sometimes internet is annoying on what it finds/does-not-find. Caliper adapters do have 4 bolt holes. How does the circular rotor adapter work?
Why are the 4 holes same distance apart 130mm if you use your original caliper? - like on 997 C4?
Last edited by Siberian14; 05-11-2024 at 03:05 PM.
#96
Calipers are radially mounted as standard so to mount the caliper further outboard in order to fit a larger diameter brake disk, all you need is a spacer of appropriate thickness.
HTH
Edit: jeeper beat me to it 😀
HTH
Edit: jeeper beat me to it 😀
Last edited by hardtailer; 05-11-2024 at 02:47 PM.
#97
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From: Richmond, TX
Yes, just need the longer bolts and spacers.
I changed to Girodisc rotors in front and rear which came with their own spacers.
I preferred Martin’s spacers in front so I’m using those with the Girodiscs.
I saved significant weight with the Girodiscs over the 997 Turbo/Panamera rotors.
I changed to Girodisc rotors in front and rear which came with their own spacers.
I preferred Martin’s spacers in front so I’m using those with the Girodiscs.
I saved significant weight with the Girodiscs over the 997 Turbo/Panamera rotors.
#98
I do not understand how a flat-stepped piece of metal with a hole on the each end-step is going to bolt to a 130mm-hole caliper. Would actually 4 holes be needed, 2 @ 130mm to bolt the adapter to its original mounting place, and 2 more to bolt the caliper to its "new" farther away from center position to fit a larger diameter rotor? Or... does a 350mm rotor still fit in the standard caliper that had a 318mm X 28mm rotor?
In other search I found that a 2015 Panamera S rear rotor is 350mm X 28mm. They look fairly inexpensive, ~$250 each. Would this rotor fit your circular adapter? Rotors suggested from RockAuto are "Out of Stock" and do not seem to be available any more. The problem finding a rotor is P-part nos. are just that, no description of dimensions to see what will/won't fit. Adding an 8mm spacer is not a lot - is that the thickness of the circular adapter? Has anyone found a cross-drilled vented rotor similar to the standard S/Turbo rotors?
Are different wheel bolts needed or replaced with wheel studs (as in the air-cooled P cars)?
Can you post a photo of your Big Brake Kit (BBK) ? Confused. Maybe TexSquirril has answers?
OK, I JUST NOW "found" Martin Hill BBK on eBay. Good grief, sometimes internet is annoying on what it finds/does-not-find. Caliper adapters do have 4 bolt holes. How does the circular rotor adapter work?
Why are the 4 holes same distance apart 130mm if you use your original caliper? - like on 997 C4?
In other search I found that a 2015 Panamera S rear rotor is 350mm X 28mm. They look fairly inexpensive, ~$250 each. Would this rotor fit your circular adapter? Rotors suggested from RockAuto are "Out of Stock" and do not seem to be available any more. The problem finding a rotor is P-part nos. are just that, no description of dimensions to see what will/won't fit. Adding an 8mm spacer is not a lot - is that the thickness of the circular adapter? Has anyone found a cross-drilled vented rotor similar to the standard S/Turbo rotors?
Are different wheel bolts needed or replaced with wheel studs (as in the air-cooled P cars)?
Can you post a photo of your Big Brake Kit (BBK) ? Confused. Maybe TexSquirril has answers?
OK, I JUST NOW "found" Martin Hill BBK on eBay. Good grief, sometimes internet is annoying on what it finds/does-not-find. Caliper adapters do have 4 bolt holes. How does the circular rotor adapter work?
Why are the 4 holes same distance apart 130mm if you use your original caliper? - like on 997 C4?
This kit is for using a 6 pot caliper and a 380mm rotor.
The kit in this thread uses the stock caliper with a 350mm rotor. It uses a spacer on the caliper and on the hub that centers the rotor.
giro only needs the caliper spacer.
Last edited by hbdunn; 05-12-2024 at 02:32 AM.