312x25 vs 314x30 rotors

[Berserker]

What are the differences between the 312x25 US and 314x30 Euro A8 rotors? I've got a friend here that's got some custom brackets he had made for fitting 996/Boxster S calipers over the 312x25 rotors that he's willing to trade to me for some parts off my parts car 200q20v.

After reading threads about rotor thickness on here, I'd like to go with the 314x30 rotors if possible.

Is the hat height/rotor offset of the 30mm rotors the same as the 25mm rotors? If not, how much machining would have to be done to the strut face of the bracket to fit the 30mm rotors instead?

This is all for a 200q20v with US UrS4 G60 struts.

Thanks!

[Corey]

Totally different offset and you would not have much material left on the bracket after machining.

[Berserker]

Totally different offset and you would not have much material left on the bracket after machining.

Bah, that's what I was afraid of.

Which rotor is offset more? This would position the caliper differently away from the spokes of the wheel, correct? Meaning, when I test fit one of my wheels on the car with the 25mm rotor, and I would need a small (<5mm) spacer to make things work. Would I be better off with the 30mm rotor and proper brackets?

Is there somewhere I can look this information up, or do I have to rely on trial and error and forums like these? I'm not all that good at using the Brembo catalog online, and I can't find the 312x25 US A8 rotor on there anyway.

Just to verify, I can use the 996 rotor over the 314x30 rotor using RS2 brackets, correct? Guess it's off to search the archives.

[Corey]

Bah, that's what I was afraid of.

Which rotor is offset more? This would position the caliper differently away from the spokes of the wheel, correct? Meaning, when I test fit one of my wheels on the car with the 25mm rotor, and I would need a small (<5mm) spacer to make things work. Would I be better off with the 30mm rotor and proper brackets?

Is there somewhere I can look this information up, or do I have to rely on trial and error and forums like these? I'm not all that good at using the Brembo catalog online, and I can't find the 312x25 US A8 rotor on there anyway.

Just to verify, I can use the 996 rotor over the 314x30 rotor using RS2 brackets, correct? Guess it's off to search the archives.

The 30mm disc has the deeper offset (it would sit closer to the strut), yes you can (I believe) bolt the 996 caliper with the 314x30 and RS2 bracket on the G60 strut. Though I haven't tried this as we never got that strut over here.

STFA over on Audiworld

[Tommy200rs]

What are the differences between the 312x25 US and 314x30 Euro A8 rotors? I've got a friend here that's got some custom brackets he had made for fitting 996/Boxster S calipers over the 312x25 rotors that he's willing to trade to me for some parts off my parts car 200q20v.

After reading threads about rotor thickness on here, I'd like to go with the 314x30 rotors if possible.

Is the hat height/rotor offset of the 30mm rotors the same as the 25mm rotors? If not, how much machining would have to be done to the strut face of the bracket to fit the 30mm rotors instead?

This is all for a 200q20v with US UrS4 G60 struts.

Thanks!

I have both calipers in use ( the blue one and the red S one), Blue is ok for Euro A6 312x25 disc (was it -96 or 97 V6 A6 ?) with special (BIRA) bracket. 312x25 has much less offset than in the 314x30. 314x30 fits very goof with boxter S caliper when 1mm is machined away from each pad support pin end. Originally the caliper was designed for 28mm disc at Porsche.

Check from etka where the 312x25mm is mounted in euro cars. In US they wanted to save and put the 312x25 into A8. Stupid factory mod..

[Berserker]

The 30mm disc has the deeper offset (it would sit closer to the strut), yes you can (I believe) bolt the 996 caliper with the 314x30 and RS2 bracket on the G60 strut. Though I haven't tried this as we never got that strut over here.

STFA over on Audiworld

NEVER!!! The forums that this question would be best posted in are more or less pure evil. I do post on AW, but only to provide information, almost never to ask questions.

Anyhow, I got the answers to the questions I asked here, in a timely and friendly manner, without being told to STFA as the first response. For that, I thank you guys.

So, in essence, I'd get a little more spoke clearance with the thicker/better rotor. Just have to work out the bracket, as it looks like the UrS4 people over here are running a custom bracket.

It seems that if the 314x30mm rotor is closer to the strut, nothing would need to be machined from the 312x25 bracket, but that a spacer would need to be made to move the 312x25 bracket back a little further from the strut. Maybe that's the solution...

Awesome.

[Tommy200rs]

BIRA makes adapter for both 314x30 and 312x25.
http://bira.org/
system 1 and system 3