Backmarker

Hi folks

Locals may have noticed that I have not been around instructing or even driving for a while. I'm doing a startup so that I can buy mooty's 4.0 and just don't have the time.

Meanwhile the GT3 sits in the garage and goes to work Fridays, and I am thinking of taking it in another direction.

I've always hated the solid iron rotors I put on for the track (philosophically) and plan to put the PCCBs back on for street use (and a massive unsprung weight advantage that will drop my commute by almost 2 seconds)

Looks like the 997 GT3 guys are selling their 380mm gen ii pccb rotors just like many of us sold our gen i's. So I got to thinking, maybe I throw some big boys up front

Does anyone know what would be involved? eg hub change up front, or hub + calipers?

0396

Great questions. What are Gen 2's going for these days?

v12man

All you need are longer bolts, 15 odd mm spacers, the 380mm PCCB disks, and new wheels that will fit the combination.

The wheels are the biggest issue if you want to stay with 18" wheels - not much available that fits.

cfjan

So the 997.1 PCCB rotors have the same offset as the 996.2 ones?

v12man

Offsets are the same 996.1, 996.2 997.1 997.2 (steel and PCCB) - rotor sizes are different between the models, but offsets are the same.

Porsche make an adapter mount that converts from 350 - 380mm using the wide bolt spaced calipers.

997 351 505 02 - I have 2 of these on my workbench, alongside a set of 997 cup brakes and 911Slow's BBS wheels - now I need to get motivated to put it all together, but a small challenge called www.cape-epic.com is using all available free time unfortunately

911SLOW

Pics or it didn't happen

TrackDays247.com

380mm = different pads than 350mm - inner clearance to clear the hat section -

v12man

"380mm = different pads than 350mm - inner clearance to clear the hat section"

PCCB 380mm disks use the same pad profile as the 350mm disk - the steel 380mm porsche disk uses a slightly narrower pad - yup - I measured them to confirm that as well.

cfjan

If 380mm has a clearance issue with the stock 18" rims, I think company like Giro should just make a "in-between" size upgrade (not that the stock size at 350mm is lacking)..

365mm disc that come with 7.5mm spacers and longer bolts.. should be easy to do.. !

v12man

JZ Machtech do a 362 setup using Alcon discs - VERY nice.

http://www.porschetuningparts.com/po...on-brakes.html

http://www.porschetuningparts.com/po...disc-bell.html

cfjan

Yeah, I knew about the Alcon setup.. love it except the price! Hence my comment about Giro making it as it would be the same price as their usual setup, I am guessing.. !!

HiWind

Pity you have to buy new wheels to do this .... But then again why need 380 on a road car anyway. Only if the 7s are cheaper/easier to find than the 6s I guess.

PointBy

I'd also wonder it the ABS and Master Cylinder would be able to correctly support the larger discs.

powdrhound

You can not just put 15mm spacers and use your old style 6 pots to go from 350 to 380. The old style 6 pots (996 GT2/3) will not space out correctly because the caliper design design employs offset 146mm bolt spacing which will not allow the caliper to radially space out evenly with the same size spacers. It's hard to explain or envision until you try it. As you space out the Gen1 6 pots, the bottom of the caliper will contact the the 380 rotor while the top of the caliper has about a 3/8" gap. The only way to go from 350-380 is to use the Porsche adapter 997-351-505-02 and bolt on the new style 6 pot calipers that have a symmetrical 225mm bolt spacing. I am dealing with that right now...

powdrhound

duplicate post