Drilled & Slotted Rotors Question (PICS!!!)

[MS203]

Hey all,


Recently found out my front pads and rotors need replacement. So I ordered front rotors from ECS. I got the 2 piece tru-float drilled and slotted pair (https://www.ecstuning.com/Audi-B8_S4...ont/ES2681113/) and paired them with EBC Redstuff pads & SS lines.


Had them installed and bedded properly, and now 1,000 miles of city driving later they are broken in. While I understand that these are more so for looks than performance gains, i have a few problems and questions.



1. there sometimes is vibration when braking. it doesnt happen every single time, but randomly when braking semi hard i can definitely feel a moderate vibration. Its something only the driver would really realize. it can happen when braking from 30-10 but also from 60-30 and so on. thats when i have noticed it the most.

2. yesterday i took a long road trip on the highway in the rain. This is actually the reason why i felt the need to post this thread. Honestly braking felt super sketchy and unsafe the entire time. I would be crusing at 70 and hit the brakes and there would usually be some sort of sound when braking that goes along with the vibration. Additionally, the initial bite seemed horrible in the rain. Im guessing this is due to water getting built up in the holes and slots in the rotors...

3. While on the highway in the rain, i also noticed that toward the end of my 1.5 hour trip, the car would begin to pull pretty hard/veer to the left (driver's side) anytime i hit the brakes... this was horrible and also scared me. there wasnt much traffic so i tested it out a little. i was in the middle lane at 70 and hit the brakes and the car would veer moderately hard to the left, almost enough to cross into the other lane. im almost positive that this issue is due to the rain, and not the pads/rotors because the next day was dry, i drove my car, and braking was perfectly straight.



if anyone with non-stock rotors or pads could weigh in that would be great! and much appreciated.






other thoughts: the rotors look AWESOME, they look great with my stock calipers painted red. I also have noticed that the stopping power seems to be increased when im actually braking hard. Which is due to the EBC redstuff pads. Also if anyone is on the fence about getting SS lines - definitely get them if you upgrade your brakes. totally worth the $100. They truly give a MUCH firmer pedal feel and im very pleased with them so far.



PS: the lip is custom fabbed by a best friend of mine. If you're interested let me know and I can give you his contact info. He's posted a few pictures on his instagram account which has gotten a lot of attention and has already taken 3 orders for the same lip! price is very fair and reasonable. For those who are not looking to drop $700-800 on a lip, you should definitely look into this. This one cost me half the price. will fit the B8 as well as the B8.5. and no, they can't be made in CF.... YET. Instagram is @baloghbodyworx and @drth_v8r, feel free to drop him a DM. If you're not on IG, Just send me a PM on here and i can give you his Cell or email.


sorry for the messy garage and the ugly stock 18's! - took these pictures when we were in the midst of cleaning it all out, and the 18's are on for winter but I am planning on going with gunmetal Avant Garde M510's w/ Super Sports in the spring time. cheers and happy holidays

[boostx2]

Stock rotors and pads here, and I had the same experience with pulling to the left during/after yesterday's rainy road trip. Initial weak but after long cruise stints was noticeable, but probably not unexpected in the very wet. Braking seems perfectly normal and straight today in the dry. Car is new to me (about 3 months) so this was the first long drive I've done in the rain.

Anyway, seems very similar to your #3 observation. Some sort of left-to-right balance issue?

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[boostx2]

Weak bite, I meant....

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[OnEaNgRyBuNnY]

Yeah I have the same setup with you but other pads and don't experience any of what you're talking about.

As for no performance gains, I disagree. Fade is gone and, in my opinion, that was the biggest issue with the stock setup. Plus they weigh less and do look sweet! One stop from a run at the strip bringing her down from 120 by 60 the pedal feel turned to mush and the braking power was significantly reduced. No longer.

I also didn't do anything to break them in besides the initial bedding. What did you do to break them in?


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[LaCross]

Did you notice any difference from the weight loss? ECS doesnt sell just the rotor rings, so I've found these to be a particularly poor value

[OnEaNgRyBuNnY]

I understood that if you call them they do. They just don't list them.

But not anything noticeable, no. Between those and some light rims one might notice something. My butt dyno isn't that in-tune.


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[LaCross]

I had asked ECS and was told they do not. That employee could have been misinformed though.

[Jv218]

That front lip is amazing how's the durability of it?


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[OnEaNgRyBuNnY]

I had asked ECS and was told they do not. That employee could have been misinformed though.

I equally could have been but I was told they do???? :/


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[torinalth]

I equally could have been but I was told they do???? :/


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per Jason, they do not sell replacement rings. Their solution to that is to call in your replacement order and they can pull up the previous order and discount the replacements as if you were just getting rings.

[OnEaNgRyBuNnY]

per Jason, they do not sell replacement rings. Their solution to that is to call in your replacement order and they can pull up the previous order and discount the replacements as if you were just getting rings.

Can't argue with that! Thanks for the info.


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[bhvrdr]

The vibration is probably from the slots in the rotors. The harder you brake with slotted rotors the more pad material you can get in the slots and the more you can feel it a bit. It shouldnt be bad but with some pad compounds you can notice it more than others.

The weak bite is likely related to pad compound. Make sure to really bed-in the brakes...really and if that doesnt improve i'd try a different pad compound next time. I wouldnt have gone with Redstuffs. No biggie. Try OEM or ST next time.

Mike

[hotleadsingergu]

For reference: Drilled brakes are actually no better than non-drilled...it's purely cosmetic; in addition, they lower the overall strength of the rotors and introduce a much higher chance of failure.

Slotted brakes can be helpful (though you'll have to live with a totally different feel and sound than non), but drilled can be outright dangerous and useless.

[mavz]

For reference: Drilled brakes are actually no better than non-drilled...it's purely cosmetic; in addition, they lower the overall strength of the rotors and introduce a much higher chance of failure.

Slotted brakes can be helpful (though you'll have to live with a totally different feel and sound than non), but drilled can be outright dangerous and useless.

I would probably add drilled is a potential weak point in high temperature applications (track days, etc)... you shouldn't have issues in day to day driving or even some canyon carving.

[wwhan]

I have Girodisc two piece rotors, with slots. When they were new, they did pulsate, until the pads were broken in (less than a week), now they are perfectly smooth. The calipers are the 4 piston Q5 Audi/Brembos with the low dust Q5 pads. Works well & is very linear.

[OnEaNgRyBuNnY]

The vibration is probably from the slots in the rotors. The harder you brake with slotted rotors the more pad material you can get in the slots and the more you can feel it a bit. It shouldnt be bad but with some pad compounds you can notice it more than others.

The weak bite is likely related to pad compound. Make sure to really bed-in the brakes...really and if that doesnt improve i'd try a different pad compound next time. I wouldnt have gone with Redstuffs. No biggie. Try OEM or ST next time.

Mike

Like I said, same setup with different pads, no issues at all. Also, the cross drill adds to air flow and helps with heat dispersion, it exposes a cross section to airflow. Though I've never studied it to determine if the air actual flows due to the rotors spinning so fast and the opening being perpendicular to the movement. They can certainly be a weak spot but much less of one of some properly. This is my understanding, correct me if I'm wrong but please let me know why. Merry Christmas!


Edit: check this link. Confirms what you were saying that drilled is pretty much just a weakness and not a measurable performance gainer anymore. I still like the look, personally, so I'm not upset.

http://m.autoanything.com/brakes/dri...ke-rotors.aspx

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[bhvrdr]

Here's a decent article about the benefits of cross drilling. Unfortunately the drawbacks tend to outweigh the benefits.

http://www.tazcobra.com/SAE_2006010691_Synopsis.pdf

Mike

[Mat@1975]

Yes,

Even for one trackday ... Keep the holes away .... !! o;)



Merry Christmas !

BR

Mat