And the caliper pins are scratching the rotors!!! We measured and found that the offset of the new 350mm rotor is around 2mm different from the original 330mm rotor.

Could I have been sent the wrong rotors? I suspect that what I got are the 996 GT3 rotors which I know has a different offset. Are 996 GT3 rotors also 350mm? If so it would confirm my suspiscion ...

They are working to go back to the original 4pot now ....

Should I have been sent 997TT rotors?

 

I have the same system. You have to mod the caliper pins a bit and it works perfectly. The wheel hubs of a 996TT are different than GT2/GT3 due to its AWD.

 

Thanks Kaizu, I was thinking of doing that, but the thing is it seems that the center line of the rotor and center line of the caliper do not line up (2mm difference!) - would that cause problems with braking and brake pad wear? In particular, would the pad that is "closer" to the rotor wear much faster?

 

I didn't experience this when I installed my 997TT front rotors... Of course, I have the Coleman Racing rotor too, which doesn't have this issue either, but I did run into this issue on the rears... 2mm is nothing to panic about... I'd clearance those pins and enjoy your new brakes...

Mike

 

I suspect what I got are the 996 GT3 rotors and not the 997TT rotors ... but then if 2mm really is no big deal I'd just shave a couple of mms off the pins ... damn I have a track event on Monday, guess I can't get my new brakes ready in time ...

 

I don't see why you wouldnt' just "grind" those pins down the 2MM and install the system... Takes a few minutes with a die grinder...You're only doing the outter two of each caliper.

Mike

 

Sorry for bringing this thread alive again. I just want to make a final check: has anyone ever successfully installed 996GT3 rotors with GT3 6pot caliper on a 996TT, without modifying the calipers?

I am been reassured by the vendor that he ships the kit with the 996GT3 rotors and all his other customers have installed the rotors without modification - which is a puzzling to me since it is contrary to what I am reading here. Plus, the rotors offset are definitely different (see pic).

Could it possibly be because I have an RoW car? ( I am in Japan).

I am just trying to confirm that 996GT3 rotors should work - in that case I'll write it off as a RoW difference and just go to the stealer and buy a set of 997TT rotors, since they are definitely not working on my car and I don't really want to modify the caliper pins (call me a perfectionist)

Mikelly, thanks for your pms - I am just looking for a third opinion.

Ron

 

I don't want to get into any pissing contests with any of the vendors, but I know for a FACT that the 996GT3 rotor WILL NOT WORK with the 996TT upright. The face of the hat to rotor face offset is different and will not work. 996GT2/3 are the same... 996TT is different. It's just that simple. If your vendor has a GT3 rotor and a TT rotor, they can pull those measurements for themselves and see what I'm talking about...

As to who he's sold them to, I can't speak to that, but the GT3 rotor will NOT clear the caliper posts because of the offset issue.

Mike

 

Below are the part numbers associated with the three STEEL rotors in question.

GT3
996.351.409.9H
996.3514.10.9H
Turbo
996.351.409.02
996.351.410.02

GT2
9963514099H
9963514109H

Mike

 

Take a minute to read Mike's sticky thread on the 996T brake upgrades. When you use a 996 GT3 caliper on your turbo, it's best to match it with the 997T rotors instead of the 996 GT3 rotors. They both 350mm, but the 997T rotors actually fit!

Not to mention that the 997T rotors are a ton cheaper to replace.

And one last thing on the part numbers posted above. The turbo numbers are kosher, but the 996GT2/3 rotors actually supercede to the 997 GT3 rotors which are part numbers: 997.351.409.90 and 997.351.410.90. Same rotors, same price....easier to find.

 

Thanks Steve. Guess 997TT rotors are the way to go. Too bad we don't have discount parts dealer like yourself in Japan! Stealership is charging me 38500 yen per 997tt rotor (~US$350)!!!

 

Ouch, that is pretty rough! I bet after the cost of shipping rotors to Japan it would be about the same price for us to shoot them over to you, though. Let me know if you ever come by the states, we'll fill up an extra suitcase full of parts for you

 

Just to put this to a close, I went to the stealer and bought a pair of 997 TT rotors for 80000 yen (US$800). The offset is the same as 996 TT rotors and it was a perfect fit. Thanks Mike for your kind advice.

The vendor still insist that none of his other customers have issues with 996GT3 rotors (even though the offset is obvious 2mm different). I have to say this is a very disappointing experience.

 

Well you have the new GT3 rotor and the new 997TT rotor... take pics, and post them up... THAT is the answer. There is NO WAY a 996GT3 rotor will fit on a 996TT upright and NOT cause interferance. If anyone else buys that package, they'll run into the same problem... I'm very disappointed your vendor hasn't stepped up.

Glad you got it fixed, and I'd try selling those rotors locally to someone with a GT3. Heck, maybe you could make a few bucks.

Mike

 

great info I had this problem as well.