Eeeeuuuuuuuuurrrrrt!
11-20-2012, 07:49 AM
#16
Brand listed above already, but here it is with a direct link to the product page: G37S (Akebono) - RacingBrake.com
Yes, I already have SS lines, but I disagree with your statement.
Pedal feel is a combination of actual stiffness, which can be slightly impacted by the hardness of the rotor, and much more so by the compressibility of the pads- and the the other impact is the perceived stiffness due to increased initial bite. Stronger initial bite means less pressure needed at the pedal which can trick the mind into thinking the pedal got stiffer. I think this is playing out strongly with this setup because of the slots and the way the harder iron is microwelding to the pads. This might go away after all the cross-hatching is gone (will take a while, again, because of the harder material).
Yes, I already have SS lines, but I disagree with your statement.
Pedal feel is a combination of actual stiffness, which can be slightly impacted by the hardness of the rotor, and much more so by the compressibility of the pads- and the the other impact is the perceived stiffness due to increased initial bite. Stronger initial bite means less pressure needed at the pedal which can trick the mind into thinking the pedal got stiffer. I think this is playing out strongly with this setup because of the slots and the way the harder iron is microwelding to the pads. This might go away after all the cross-hatching is gone (will take a while, again, because of the harder material).
A rotor has no impact on pedal feel. The brake lines being upgraded to stainless help with pedal feel. Now if you are trying to compare pedal feel to pedal distance to engage your brakes that is two different things. The benefits of the slots is to dissipate heat quicker. People are misinformed that large brakes and/or slotted/drilled brakes help you stop sooner. The benefit of large brakes is more material to accept heat and keep the temps lower. If you want to stop sooner upgrade your pad selection. Adding large brakes just means to can brake later, harder and have them cooled for the next turn.
11-20-2012, 08:38 AM
#17
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A rotor has no impact on pedal feel. The brake lines being upgraded to stainless help with pedal feel. Now if you are trying to compare pedal feel to pedal distance to engage your brakes that is two different things. The benefits of the slots is to dissipate heat quicker. People are misinformed that large brakes and/or slotted/drilled brakes help you stop sooner. The benefit of large brakes is more material to accept heat and keep the temps lower. If you want to stop sooner upgrade your pad selection. Adding large brakes just means to can brake later, harder and have them cooled for the next turn.
Drive an average G37 and you'll notice no difference at all in the brakes during daily driving or hard stops. However, repeated hard stops with all kinds of spirited driving (track, auto-x, or just general playtime
) and there's where you see the benefits of the BBK.The OP has been taking his car to the road track, where he's surely to enjoy this upgrade.
And then there's the looks... which are very, very nice. Love the look.
11-20-2012, 09:34 AM
#19
Nice upgrade, Ash. You'll love those rotors. Had mine on several track events the past couple of years and they've held up quite nicely. 
(fronts only, can't justify the rears.)
They're slotted and "drilled", the holes are inside the slots themselves.
Here's an old pic showing it.
(fronts only, can't justify the rears.)Here's an old pic showing it.
11-20-2012, 09:50 AM
#20
Mike, forgive me bc I'm pretty sure I've asked you this before, but remind me what pads you run on the street vs track with these?
Agreed on the rears. I'm looking for a good curved vane one piece to use in the back. Maybe Project Mu if i can get my hands on some.
Agreed on the rears. I'm looking for a good curved vane one piece to use in the back. Maybe Project Mu if i can get my hands on some.
11-20-2012, 12:18 PM
#22
Interesting. I'm on et800 for both street and track. The fronts smeared and made for nasty pedal pulsation but they didn't wear excessively so I'm thinking the can take the heat. I'm hoping the slotted and better cooled rotors allow me to continue using these pads.
I've read mixed reviews on 800s for track. Works fine for some and not at all for others.
I've read mixed reviews on 800s for track. Works fine for some and not at all for others.
11-20-2012, 01:44 PM
#23
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11-20-2012, 03:46 PM
#24
Ditto on the rear curved vane, if only so it matches the front visually.
One thing that irks me is since i went back to 18s, you can't really see the vanes much and to the casual (and sometimes seasoned) viewer, they think it's just a standard rotor. Not really a big deal, but then again i knew going in that RB's 2-pc rotors aren't nearly as "bling" as those from other manufacturers. Even the hats almost look like they're 1pc.
11-20-2012, 06:00 PM
#25
Thanks. I missed it.
A rotor has no impact on pedal feel. The brake lines being upgraded to stainless help with pedal feel. Now if you are trying to compare pedal feel to pedal distance to engage your brakes that is two different things. The benefits of the slots is to dissipate heat quicker. People are misinformed that large brakes and/or slotted/drilled brakes help you stop sooner. The benefit of large brakes is more material to accept heat and keep the temps lower. If you want to stop sooner upgrade your pad selection. Adding large brakes just means to can brake later, harder and have them cooled for the next turn.
A rotor has no impact on pedal feel. The brake lines being upgraded to stainless help with pedal feel. Now if you are trying to compare pedal feel to pedal distance to engage your brakes that is two different things. The benefits of the slots is to dissipate heat quicker. People are misinformed that large brakes and/or slotted/drilled brakes help you stop sooner. The benefit of large brakes is more material to accept heat and keep the temps lower. If you want to stop sooner upgrade your pad selection. Adding large brakes just means to can brake later, harder and have them cooled for the next turn.
So, I don't think your statements above are flawed really... it's just that what I've found empirically and by talking with people much smarter than me has led me to the following conclusions:
1) Pad selection impacts friction levels and compressibility which both have very strong feedback mechanisms with pedal feel and effort.
2) The pad-rotor interface is what influences the two main modes of energy conversion that result in braking force: abrasive, and adherent. Both materials play into those two modes, though the rotor has more influence in the abrasive mode than adherent because there is no pad transfer layer to speak of. This mode doesn't occur with street brakes in normal driving, but does come into play at lower temps or with racing pads at street temps. That's why racing pads can eat rotors up on the street, but not on the track.
3) SS brake lines definitely help with reducing volume change in the braking system but modern lines have improved significantly in this regard. The main reason to do this upgrade for track driving is durability. Case in point- when I upgraded the lines my increase in pedal stiffness wasn't as pronounced as when I switched from OEM pads to racing brake ET500's and later 800's.
(also, note that I had SS lines for a while before upgrading my rotors this week, which was the only change I made to the system this time).
4) And this all brings me to my thesis statement - I'm of the opinion that there is a strong psychological component to pedal stiffness that is influenced by friction levels. By having a system (not just pad) that has a strong friction level at whatever mode you are in, the amount of pedal pressure needed will be comparatively lower. This can feel like increased stiffness because of both the reduced pedal travel that is needed, but also the feedback you get from a lower pedal pressure. It's very hard to separate this from the experience of a truly stiffer pedal without actually measuring deflection against force at the pedal.
I will add that my break in is almost done (the pad transfer layer is almost fully across the radius of the rotor), and braking force at equivalent effort is noticeable higher. I attribute this to the effect that sharp slots have of deglazing the pads, plus the "digging" effect of the slots as well. Pedal modulation feels good too but that's harder to judge until complete break in.
Feel free to poke holes in my theory or other comments at will
11-20-2012, 06:17 PM
#27
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iTrader: (9)
It's OK. Everyone has their own priorities, and the more you know about your car, the more those priorities change over the years. Honestly, learning about these rotors is a valuable thing to me, so it's all good.
For example, I've been researching off and on about the 4.083 rear gear swap for the 6MT. (There... push-back, LOL!)
11-21-2012, 03:34 AM
#28
Gear swap would be A very effective mod! I wouldn't do it myself simply because i feel first gear is pretty short to begin with on my 7at, but i haven't driven a 6mt.
I did a gearing change on my old Ducati and was duly impressed with the acceleration but ended up going nearly back to stock eventually once i realized i just needed to drive her differently. Having the taller gearing at high speed mastered to me.
I did a gearing change on my old Ducati and was duly impressed with the acceleration but ended up going nearly back to stock eventually once i realized i just needed to drive her differently. Having the taller gearing at high speed mastered to me.
