A hypothetical: A 2009/10 G37 Sedan...equipped with the OEM BBK that comes with the sport package vs. OEM non-sport brakes, but with all else being equal, including identical tires! Would there be any difference in braking or stopping distance in an emergency stop? I presume the BBK's should work better and perhaps "feel" better on a track or in extreme conditions like mountains, etc., but I am asking about everyday use...for those once in hopefully not very often heavy traffic or impending accident situations. Any benefit to the sport brakes in terms of actual stopping distance?

 

None of you brakes experts can answer this? I guess what I am really asking is if you are not planning to track the car or use it in extreme conditions, is there any real-world benefit to the sport brakes?

 

The larger and more powerful brakes will obviously stop shorter than the smaller less powerful brakes all other things being equal. The thing is, I don't know that I've seen it published anywhere how much shorter. Whether it's enough to make a difference to you if you're not a track guy - extremely doubtful. They obviously are adequate for the car in every day usage because I've never hear or read any complaints about the non sport OEM brakes being insufficient.

 

I doubt it. In a panic stop both sets of brakes should be adequate to take the tires to the limits of grip, where ABS is engaged. If both cars have the same wheels/tires/suspension and identical weight, then theoretically they should stop in the same distance.

That said, you might have to "push harder" on the brake pedal without BBK to generate the same stopping power as the car with, since the BBK will have a larger contact patch and I believe 4 instead of 2 pistons. Also, if you did more than 1 stop in this type of situation you would notice diminishing performance from the smaller brakes due to brake fade from excess heat.

Again, I am just basing this on logic not on real world evidence, maybe some one else can chime in.

 

I read a thread over on driver today linking to this. It doesn't exactly answer your questions either, but gives a little more hard data.

 

When I was test driving cars for purchase I tested two coupes:
1) G37X with regular brakes
2) G37S 'vert
First drive with G37X in DS mode. I was going at a fairly high rate of speed towards my exit when all of a sudden another car pulled into the off ramp ahead of me. I STOMPED the brakes hard and I was not sure if I would be able to stop or would have to cut back out on to the highway. A little nerve-wracking, but my own fault.
Second drive was with a 'vert. I was tracing my route from my 335i drive earlier. On a straight I got the car up to about 180Kms for a second in the passing lane. Guys pulls in front me doing about 110K. I stomp brakes. No drama, just a strong hard pull down to a slower speed.

In my brief real world experience, I think the BBK is a GREAT investment and I could FEEL the difference.

 

"To this effect, we didn't do any tests based on stopping distances because, as many of our readers know, BBKs often do little to affect initial stopping distances when the tires are actually doing the stopping."

From the article, corroborates what I said.

 

Coming from an 03 G35 with Brembos, the Akebonos are horrible. You have to push the pedal halfway before the brakes start to really bite. I've driven loaner cars (non BBK) that had more stopping power than my 09 G37 S. BTW, The car was purchased brand new. I had an Infiniti tech ride with me the other day and he said that it was normal. My rear pads at 9800 miles look like they need replacement, which is ridiculous. I'm going with Project Mu B-force pads next.

 

All things equal, the non-sport will stop faster. Why? Less unsprung mass.

Modern braking systems have more than enough power to lock up the tires; stopping distance is limited by tire grip, not by braking power.

What a BBK provides is a more constant force over a larger area, resulting in more even brake pad wear, more fade resistance (due to increased surface area to dissipate heat, and increased mass to absorb the heat), and ultimately, cheaper brake pad changes.

For your average user, a BBK is overkill, and a lot of people don't like the "click" from brake knockback.

 

In real road testing, a panic stop won't be much different between the two. The limitations are the grip of the tire on the road surface, ABS and initial pad bite. If using the same pad compound on the same road surface, the panic stop distance won't be much different. One caveat: If the pad compound has a rising rate of response with temperature, the system with the smaller pads (non-Sport) might actually stop slightly shorter due to more heat being built up in the pad more quickly than the larger pads in the Sport calipers. But this might be only a foot or two, which is difficult to repeat when taking measurements.

Where a properly designed BBK (better than the Sport brakes) shines is in pedal feel (much more positive), pedal response (easier to modulate during threshold braking), mechanical balance (slightly more rear brake bias), thermal balance (front and rear temps kept more closely in the same range to stay in the pads' sweet spot) and thermal capacity (more stable brake performance under heavy loading or track duty). The Akebono Sport brakes are somewhat of an improvement over the sliders in some categories and marginal in others. IMHO, I wouldn't pick the Sport package for the brakes alone.

Chris

 

This is all obviously anecdotal, but as a driver w/ non-“BBK” brakes I have to say that for the daily drive, they work awesome. The non-BBK has 13” rotors which not long ago was huge by normal OEM standards. Usually you’d have to buy an exotic to get over 13” stock. Between the two large pistons and casing of the caliper, there is plenty of contact patch between the caliper and rotor. I do have experience with other vehicles, upgrading from stock to BBK and it helps A TON on track days to reduce fade but it never really felt to me like the stopping distance was shorter. That being said, can’t wait to get a BBK cause they look SICK!