I cant (read dont feel like it) read this whole thread. my reason for not initially being interested is my brake set up is perfect. not a secret and those who care can do a search. this was suggested and set up and maintained at a pro race shop. Bob Brooks, aka "Viper Bob" did it. he did it in direct communication with Brembo guys.
I dont proclaim to know anything about anything, except how to make a TT perform at its best on a track.
lot of good info from smart guys above I dont feel like refuting.

for the record I run the new Brembo calipers on the front and Pagid just came out with a pad for it, (was using Ferrari pads custom cut). these are the upgraded 6 pots with the cross bridge in back (search my threads if interested)

I run pagid yellow 29's front and black rear to address brake bias.

I assume somewhere in this filabuster that there was a comment on you dying if you run the rear 997 GT3 calipers (correct me if I'm wrong)

anyway that is what I have run for about a year now. on my 4th set of pads and hundreds and hundred of track miles

no problems..

not saying that it is right or safe for anyone, just what I do.

I will ask Bob to chime in and try to find in this thread what the problem is supposed to be.

 

for clarity, I run the 997 GT3 rear caliper and rotor. I "assume" that is ok as the caliper and rotor is matched. is that the problem with what you are saying others are doing wrong... hope so cause that gets me off the hook!!

 

Tom,

I'm running the same front brake setup as you but my greater saphenous vein almost ablated itself when I heard the price for the Pagid Yellows out of Germany. Well into the 700's for a pair.

I've been running the PFC 01's but have just purchased a pair of the PFC 06's which should last longer with equivalent torque. I'll report performance and longevity after I use up the rest of the 01 compound.

I belive the installation of the Brembo GT kit on the rear will give me more minutes on the front pads but that remains to be seen. Road Atlanta next weekend will tell.

 

personally, I don't think it's worth the added unsprung weight as I don't have any issues with my rears being "under braked" or too much front bias. if you do you can always try and mix different pads.

 

Adding larger front brakes without doing anything to the rear is no problem at all other than having to buy a lot of replacement (expensive replacement) pads for the Brembo Monobloc front brakes. I tried your company's recommended Ferodo 3000's and went through over half the pad thickness in a 20 and 25 minute session. Also had pad fade with them which never happened with either the PFC 97 or 01 compounds. Same track with similar ambient conditions. Your company was very upstanding in making it right with me, and that's a tribute to Race Technologies. Gary knows.

I, in addition to Mikelly, found no clearance problems when running the 997 rotors on the rear with the 996 calipers for the short time I did so. I have just switched to your GT kit for the rear and am hoping for better balance and more pad longevity, both front and rear.

 

Tom, he's saying that running the 997TT rear caliper is a problem and will cause premature ABS cycling, due to rear wheel lock-up, if run with the GT3Monoblock OEM caliper and 350MM 997TT front rotor, eseentially what several of the vendors (including suncoast and UMW) are selling. It has more to do with brake bias and volume/port/bore in the caliper piston, master cyclinders along with the ABS sytsems programing.

Funny thing is, I know several guys running this exact kit with ZERO issues. I don't proclaim to be a Porsche brake expert, and I don't play one on TV. But I ask a lot of questions from what I "think" are very smart guys in the Porsche racing community, and relay what I'm told.

I also chat with others at the track to find out what they're using and what works for them. I have heard ZERO issues concerning what Mark from Brembo has relayed. That said, I have no reason to upgrade anything in my current setup, as it works well using the 997TT front rotor/997GT3 Caliper and the 996TT rear caliper with the 997TT rear rotor and the spacer that Al mentions above!

Mike

 

Mike correct me if I'm wrong, but my UMW system, is front and rear 996GT3 calipers and rotors are 997TT rotors at all corners. All I know is this system stops my car much better than the stock system did, and I have not had any problems with it.

 

It was my understanding (and pad fitment is the same exact partnumber) that the 996GT3 and 996TT rear caliper are the same. The rotor is the issue... Hat "offset" for the rotor is what causes us problems, which is why the 997TT rotor is such a wonderful invention!

If that's what Kevin ships, then I stand corrected... Thought he was shipping the 997TT rear caliper...And I don't have his kit, so I'll assume I was wrong.

Mike

 

This is what I would like to upgrade to. Where would I get the spacer?

 

Scott,

You will have to get someone to make them for you unless you have the proper equipment.

I have spacers, rotors, 997 bolts and 3 sets of pads for sale in the "For Sale" section of this forum

Al

 

My original caution was that the brake balance shifts too much to the rear with the 997TT rear calipers installed. The ABS function was a concern but as I had said later, I couldn't confirm as I haven't tested that combination. From those that have these installed in practice, it does not look like it is an issue. (We've tested some vehicles where once the ABS kicked in the max rate of deceleration was akin to driving on ice).

However, those that have installed these calipers and used them have staggered the brake pad compounds to bring the balance back in line with what it should be. I may have missed a couple posts, but I believe this has been on track-only cars. For street, you would have to have a pretty lousy pad in the rear to bring the balance back.

I have looked at the CAD model of the 996 caliper positioned on a 350mm rear disc. It clears but is quite close. Closer than we would recommend. The disc does grow in diameter at high temperatures, and could contact the caliper. From the people that have done this setup, it doesn't sound like that has happened.

To me, this begs the question of why to install 997TT calipers on the rear, if you can use the larger disc with the OE calipers (and requisite spacers and bolts of course) and not have to fool around with brake pad compounds to get the balance right. This has the added benefit of assured ABS performance and a better pedal feel too. <CYA On>Though officially, of course, I can't recommend this because it doesn't meet clearance standards, etc., etc.<CYA Off>

 

I question your logic here, and here's why...

I measured (I still have the OEM stock 996TT rotors/bolts) the distance between the 996TT rotor/caliper and the 997TT rotor/996TT caliper. I was concerned about expansion due to heat. I found that with the spacer I spec in this thread that there is ZERO difference in distance for growth/ expantion due to heat.

I put 15 days on the old 996TT caliper/997TT Rotor this year with zero issues. I got 9 days out of the Pagid RS29 pads. My car used Pagid Rs29 pads front and rear, so no "balance" of bias, and I'll toot my own horn here in the fact that a number of instructors asked to ride solo with me in the advanced solo run groups and ALL commented that my car was stable in suspension and braking, and all I mention wanted ride for the sake of "track orientation" and not "instruction"...

You know far more about this topic than I... So please, explain.

Mike

 

Buy Al's setup or you're a fool!

Mike

 

I have a headache!!

 

I don't see anything that needs an explanation here. You are running the setup that has no balance issues and doesn't need any staggering of brake pads.

The balance issue occurs with installation of the 997TT calipers on the rear, as I have stated many, many times now. This is when you have to start messing with different brake pads front and rear in order to bring the balance back in line.