I went with ET500 front and rear. I will be doing quite a bit of track but do not like any squeeking on the street. Hopefully they will hold up seeing as RB says they are 50% street and 50% track pads.

 

Yeah, I just wanted no chance of fade, if they squel too much maybe I'll pick up a set of lesser pads.

 

After removing metal from the visiable rubbed area, the rotor stopped rubbing there, but started rubbing lower down the same faces. Did not do this second rubbing at first but then stared after doing the test with HOT brakes. I then also removed about .010" from there, and now the rubbing is gone.

The area is the lower inner surface near the lower attaching point. It is marked in red. Had to remove at lease .010".

 

^^That is messed up. RB should have done a better job of making the rotors fit. I wonder if they will fix that in later production runs.

Hope their measurements on the BBK were more accurate with respect the tie rod end and other components. ..

 

cewrx7r1, please keep us in the loop on what RB does to address this. Unless you made some kind of serious installation error, this is a rather large design flaw.

-ch

 

This is with their two piece stock OEM front replacement rotors which are 2 mm thicker than stock. They only rubbed when making very sharp turns which put a heavy load on the bearings. I do not know who did their initial testing of these or how they were tested.

As a friend always told me, a mod part usually means you have to do some modifications to make it work! I am use to this fact.

I am not complaining about the parts, just informing others that they may encounter the same problem and how I fixed it.

 

would it be beter to turn down the rotor instead of grinding into the suspension parts, 10 or 20 thou off the corner of the rotor maybe? something a brake shop could do?

 

The affected area of the caliper does not reduce the strength of it when ground down some.

Reducing the rotor thichness negates the reason for it being thicker, a larger thermal mass.

 

I've been meaning to post my experience with RB and there OEM size two piece rotors. This is a ciff notes version.

Overall I am satisfied with the quality and costumer service I received from RB, they are very responsive to both phone and e-mail. Although I was disappointed that I had to make modifications to a expensive product that I had assumed had been tested.

The rotors I received are about 3lb lighter than OEM each! They are very nice pieces and are finished very well although there was a few small pits in the rings surface. I was assured by Warn that the pits will not affect performance in anyway. I was inadvertently sent two front rights, but with one phone call I was sent new hardware so that I could flip one of the rings over.

I was using EBC Yellows for pads and they would not fit with all the oem shims loaded. The pads had a "brake in coating" that appears to be painted on the pad and an insulator on the back. These pads plus the shims are 17mm thick each. The rotor ring is 24mm ( 2mm over OEM ) distance between the caliper pistons is 56mm. After conferring with one of the RB’s engineers, I loaded the pads without the shims and ran the pads in, then installed the shims. As Warn has said, the thicker rotor rings add thermal mass for better performance, but they are also the same rings used for the WRX.

I had contact between the rotors and the inboard side of the caliper when the wheels were turned to full lock. For some reason the calipers are not centered on the rotors (even the OEM rotors) by .020 out board. I added a .010 shim between the caliper and the mounts. I was told by Warn they were going investigate further and make any necessary adjustments.

I have had the rotors for two track days and although I’ve been able to push the pads to fade, the rotors have shown very little wear.

 

Ah, I had not realized they were thicker than stock.

Interesting feedback from yourself and Gadd. Thank you both.

 

Thanks Gadd and Chuck for your feed back.. I'm just crossing my fingers that the BBK kit will have zero issues regarding fitment and "modifying".

 

One correction on the weight

They are 1.5lbs lighter each not 3lbs.

Paul

 

The stock front rotor is 22.0mm with 6.0 plate thickness.
The stock caliper can theoretically take 24mm rotor with a groove width of 25.4mm

When we designed a two piece rotor we typically add improvement to make up some OE one piece rotor deficiency instead of duplicating from OE and reducing the weight, thus we have increased the rotor to 24.0mm (7.5mm plate thickness) which has substantially increased the heat capacity for serious tracking yet still with weight saving of 2.3 lbs. per rotor. We have included this information of thickness change in our product description.

Be aware the OE caliper is a mass production model i.e. the groove was “as casted” instead of machined, and is of side (axial) mount (like most Brembo calipers supplied to OE) instead of radial mount so they tend to flex more.







In fact our two piece rotors are precisely machined and assembled to have the exact offset (from the hub surface to the center of disc) as one piece rotor, but unfortunately not the OE caliper which you can verify your OE set up with stock rotor of 22mm the caliper is not perfectly aligned with rotor however it’s only 22 mm so you probably wouldn’t feel the deviation in alignment nor the interference.

When we test mounted the two piece rotors they fit fine but when they were under sharp turning or heavy braking the interference (due caliper flex) may show up as some customer have experienced – This interference can vary from one to the other in fact not all customers installed our two piece rotors have the similar complaint.

Unless we hear from you that you rather to keep this heavier disc with advice to have customers shim the caliper for proper alignment we can easily scale the disc thickness back to 22.0mm rotors. Please voice your opinion.

Upon reading the above I hope you get a better idea how we designed our brakes with improvement. That’s why we prefer to design and supply the complete brake system than partial to eliminate this kind of happening. In fact we even make our rear BBK caliper bracket to compensate the incorrect OE offset by eliminating the use of shim.

 

I vote to keep it at 24mm.

The mods that Paul and I did ( .010" shim or a little grinding) to fix the problem is very easy to do. The extra thermal mass is more important than the little extra work that we did to fix the problem.

If you can not figure out how to do this or are not willing to do it; stop trying to mod the car and stop pretending to be a mechanic or car enthusiast. Think about how much time and effert that Howard and RB have spent to come up with these great brakes, you can do the same.

 

Thanks for your opinion and I think you made a very good point here in terms of modification involved vs. the benefit gain.

To assist others get a better idea of how much .010" (.25mm) is to remove, it measures to 2.5 sheet of 20 lbs paper.

This is your community so let your voice be heard.

 

As stated, the stock calipers are castings and there are production tolerances involved. It is impossible to increase the width of the rotor and reuse the stock calipers without having some cars be affected by the reduction in factory "slop".

If you want a perfect fit, spend more money and buy a set of rotors and calipers designed to work together. If you want to save a buck by reusing your stock calipers, be prepared to modify them. It's not like the Mandeville kit didn't require modification to the stock calipers. Even my AP Racing brakes didn't fit perfectly without shimming. Keep the extra rotor width and deal with it.

BTW, nice work on producing this kit. If I didn't have ~$5k in the unused braking upgrades on my car, I'd be a customer too.

 

Sorry i wasnt clear, i did not mean to turn down the "rotor thickness" but to just ease (round over) the corner of the rotor that rubbed, i would prefer this to grinding into other parts....
i see this would not help the inner caliper groove issue which looks very simple to correct in the field.... just the subframe type of contact shown in earlier post.
I agree that making the rotor thinner is not acceptable......

 

How many of you that bought the full kit have an upgraded 929 master cylinder? Do you think it is mandatory with this kit?

 

From the information that's been posted so far, the 929 master should not be required due to the fact that the RB front caliper very closely matches the piston size of the OEM caliper.

You may choose, however, to upgrade to offset the decreased pressure necessary to achieve lockup. That's more down to driving style: whether you find it easier to modulate with a higher pedal pressure at lockup. But engagement should happen as quickly as it does with the stock calipers.

For people who like to heel-toe, a softer pedal can be more manageable. (Please note I'm not talking about a soft pedal from fluid boiling or pad fade.)

The 929 upgrade became popular due to the extremely large pistons sizes that are standard with most BBKs for the FD. For example, the AP 6-pot has nearly 122% the piston area which meant that engagement was significantly increased. The 929 moves more fluid for the same pedal displacement.

-ch

 

My FD has Wilwood SL6 (6 piston) calipers on the front. Though it had been stated that I would need to upgrade to the 929 MC, I don't find that to be true. The stock MC has been fine.

I wish I had held off on the brake upgrade. For ~ $200 more than I paid for front brakes, I could have bought the entire RB setup.

 

Thanks for the commentary(s) on the master brake cylinder. This is good. Simplifies my life.

 

bump...

 

the RB 440 front calipers and pads were shipped to me tuesday. they should arrive this thurs-fri.

i will have pictures up the day they arrive. my rear flares should be finished (enough) to get on the road sat.

expect things to get a bit more exciting real soon.

howard

 

sigh... why didn't I see this before the 15th?

 

I am really interested in this kit but no one has seemed to address the problems of ducting and pad knockback. These are the only things stopping me from doing the upgrade.

The two sided mounting of the rotor seems to prevent putting any kind of ducting into the rotor eye. I think I would almost prefer the standard style of hat attachment.