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Important Brake Lessons Learned

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Old 03-28-2007, 12:11 AM
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Jim H.
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Default Important Brake Lessons Learned

Thought I would share with you guys a near catastrophe (or two) I almost experienced during some recent brake upgrades and maintenance.

First off, I had OEM rotors on my car and was looking at them hard to see if I could get another weekend out of them. They looked okay according to all of the general wisdom, but, I had a 3 day track weekend coming up and didn't want to chance it. As I was changing them out, I was lamenting that they were probably still good but then, ahah!. turns out they weren't ...

(see first two pics)

Lesson learned. Gotta look close. I see over 155mph on the back stretch at Mid-Ohio and I hate to think I was almost doing that on brakes that were unquestionably gone.

Well, good time to upgrade brakes anyways. PMNA was out of stock of the cup rotors at the time, so I plunged into a set of Direct Drive PFC floating rotors

Thanks to info on this site and on renntech, the install went easy and I ended up with this...

(third pic)

So far so good, and in the process I found a small craftsman bar clamp that made spreading the pads SUPER EASY and safe on the calipers. Life was good.

After finishing up both fronts and installing my one weekend old RS-19s, I was getting ready to go bed things in and happened to notice something. The pads didn't fit right and were riding up on the inner lip of the rotor. Worse, the backing plate of the pads was near the plane of the studs that held the hat to the rotor! Like this...

(fourth and fifth pics)

Time to get on the phone and see what's up with this Turns out that PFC direct drive rotors are only supposed to be used with PFC pads. The swept area of the PFC rotors is a few millimeters smaller than the OEM rotors. This was supposed to be known by the folks who sold me the rotors but alas, human error won out. Ouch. It would have been easy to take off and bed in the new rotors and it may have worked okay...for awhile, but then again it may have been disastrous right off the bat. Eventually, something bad would've happened I'm sure. Interestingly, things went together very easy and the rotor spun freely with no binding with hand spinning. It wasn't blatantly obvious that something was wrong.

Oh well, no harm no foul. Performance Friction was very receptive to my findings and labeling suggestions. They made things right on their end. I am impressed with their products and with their support. If their braking components work as good as they say, I'll stick with them no problem. Track report to follow...

Oh, and I managed to get some cup rotors shipped to me rather unexpectedly in the process. They are available if someone else needs them (see other post).

Summary lessons learned.

1. The cracks that take the OEM rotors out of spec can be very subtle, so look carefully.
2. Check and double check safety equipment (brakes, harnesses, etc). In this particular case, a good axiom to live by (pun itended).
3. Be careful about mixing different manufacturers equipment (PFC and Pagid in this case).

Hope the pics lined up right and show good detail (shoot they got added at the end).

Take care.

Last edited by Jim H.; 05-01-2013 at 06:34 PM.
Old 03-28-2007, 01:19 AM
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Mr Michael B

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The AP rotor set for the rear is similar. You can use AP supplied shims to move the caliper out a fraction and away from the row of bolts. AP instructions note this clearly. Good catch on your end.
Old 03-28-2007, 01:43 AM
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RJFabCab
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Jim,

Good pickup.

Some of your cracks look rather long... on the order of maybe 7mm. Runout looks ok, but I would've tossed that set probably before that one crack reached the edge.

No way would I chance those Pagids on the floating setup with such small clearance.

The new rotors look nice!

Cheers
Old 03-28-2007, 07:29 AM
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Jim H.
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Yep, I agree. Car is just sitting waiting for the PFC 01s to arrive in the mail. Can't wait...
Old 03-28-2007, 10:57 AM
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Seth Thomas
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That looks like the upgrade I just did on my GT3. You will love the rotors and pads. Let us know how the track weekend goes
Old 03-28-2007, 11:08 AM
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Phokaioglaukos
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Originally Posted by Jim H.
in the process I found a small craftsman bar clamp that made spreading the pads SUPER EASY and safe on the calipers.
Please share the part number/description. This sounds useful.

Good luck with the discs? I just got my replacement set of floating AP front rotors.
Old 03-28-2007, 11:47 AM
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Jim H.
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Here is the bar clamp. The jaws are small enough to fit in the center recess on the caliper for the pin. Just put one end in the caliper recess and the other on the center tab of the pad and squeeze.

$9.95 at any sears store.

From the reciept:

BRCLMP, 4-3/8
UPC: 025104345581

Last edited by Jim H.; 05-01-2013 at 06:34 PM.
Old 03-28-2007, 12:01 PM
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Qwickrick
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Would you know if PFC offers the floating rotors for 993TT? Yes, I know you have to use PFC pads with these.
Thanks in advance
Old 03-28-2007, 01:26 PM
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Hey Jim, what's the ball park cost on a pair of Direct Drive PFC front rotors?
Old 03-28-2007, 02:18 PM
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LVDell
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Dumb question but is "direct drive" a PFC version of 2-piece floating??? It looks like that from the pics but not sure. Very nice setup though.
Old 03-28-2007, 02:53 PM
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arenared
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Thanks for the post. That interference problem with the hat is NOT good. If you get desperate or want to use non-PFC pads, you could grind/dremel that backing plate or try to get the spacers that Michael B. mentions from AP. Actually, PFC should be supplying them. Did you get any chance to weigh them? On the standard 996 rotors, the hats are completely different and they actually weigh more than stock.
Old 03-28-2007, 04:11 PM
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Rob in VA
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Originally Posted by Jim H.
Here is the bar clamp. The jaws are small enough to fit in the center recess on the caliper for the pin. Just put one end in the caliper recess and the other on the center tab of the pad and squeeze.

$9.95 at any sears store.

From the reciept:

BRCLMP, 4-3/8
UPC: 025104345581
I had to change my pads at the track the other weekend and a buddy walked over and handed me that clamp. It worked like a champ! I need to pick one up now.
Old 03-28-2007, 04:46 PM
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Bill911
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I just bought these rotors for $ 1,100 including shipping for the pair.
Old 03-28-2007, 05:39 PM
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NJ-GT
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Originally Posted by Bill911
I just bought these rotors for $ 1,100 including shipping for the pair.
Bill, could you please take the weight on one of them?.

The stock front 350mm rotors weighs 26 lbs, the stock rear 330mm 19.5 lbs, and the Cup rear 350mm weighs 22 lbs.

Thanks
Old 03-28-2007, 09:45 PM
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Seth Thomas
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Two rotors, a set of front pads, a set of rear pads, and the boxing weighed in at 61 lbs for me.


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