My rotors are shot on my brand new to me 16 4S. (Thanks dealer). Looking at either the 350mm Girodisc or the Racingbrake 380mm. Not concerned about cost. These will be for street use. No track in Hawaii. Is there any reason not to go with the 380? Also does anyone have pics of these rotors behind a 20 inch wheel?

 

Lots of threads on this topic

991 rotor increase options

 

I'm not aware that there is a 380 option for S/GTS brake calipers, but there is a guy investigating that same idea in this thread here beginning at Post #153. Maybe ask @DC021 what he finds out.

I just installed the GiroDisc 350/350 kit all around and am very happy with the way they came out.

If you are interested in DIYing it, go to this thread:
https://rennlist.com/forums/991/1430...ake-lines.html

Here are photos of them front and rear on 20" RS Spyder Design wheels.

 

girodisk is the obvious choice for your needs. I went with 380mm with GT3 calipers all around and it's way overkill for only street use like you are intending.

 

from what I've seen with racingbrake you use the stock S calipers. Really want to see how they look tho.

 

not once in that thread does anyone mention the racingbrake 380mm kit I'm referencing.

 

@Arione If you're "not concerned about cost", and you want 380mm rotors, then going with a complete purpose built BBK like the one made by AP Racing seems like the smart choice and much better value which gives your 36mm thick rotors (vs 34mm with RB) and includes calipers that correctly correspond to the increased dimension.

 

I've never seen anyone with the RB kit on their car but it is intriguing... I asked a brake rotor manufacturer of a 350mm kit why they don't offer a 380mm kit like RB and he explained something about concern around the calipers on our cars using offset bolts... not sure the actual issue

One solid option would be 991 Turbo 380mm steel rotors (could do 1 or 2 pieces depending on budget) and calipers. It would be a bolt-on swap using 100% OEM components. I've seen some used kits for ~3k. Looks awesome.

For instance
https://www.ebay.com/itm/26678021437...vaR8cBk&edge=0

+ rotors

 

Good info. Really I'd like to put PCCB on, but that doesnt seem to be a good ROI. I think I'll just do the girodisc set.