Comparison test of BBK for the E9x M3 - Surprising results!!!

[admranger]

Originally Posted by 1MOREMOD

i have st and it was my low budget choice. if i had money brembo still wouldnt be in the picture it would be ap or maybe alcon. if i was building and starbucks hard parker with gold calipers then maybe brembo for extra scene points.

Well played.

PFC please.

[bigjae1976]

Brembo is out because of the monoblock caliper. And the ridiculous cost of consumables.

If money were no object, I'd get PFC or AP Racing.

[K-M3]

Originally Posted by VictorH

Seriously? This is the standard by which almost every car magazine measures braking performance and the brake pad issues was addressed by the OP. It would be nice to read this test in English but the German's are usually pretty logical and systematic in evaluating these types of things. What test would you propose that would provide better objective information?

This is probably the most objective comparison we will get regarding BBKs in our cars and appears to be well done. The fact that the results don't support what many people may have believed just goes to show that objective facts don't always fit your belief system. Thanks for posting.

+1 .... Being a future customer , it is nice for me to know what performance I can expect out of a kit as supplied by a vendor ..... Would have liked to see the Essex designed AP racing kit included in this comparo with their Essex designed AP racing calipers combined with their j- hook discs .... Smaller but apparently lighter n as effective. I am trying to cross shop between this kit n the stop tech trophy kit

[aus]

At least we can take away that the ST Sport pad is a pretty good everyday and semi track pad. I would hope all the kids were designed with the OE master cylinder in mind.
Ideally, they kits would all run the same pad on the same time, but then people would say that kit X or Y was not designed to run with the chosen pad.

This is just one piece of information when deciding what kit to buy. It's probably the best comparo so far between the major BBK's out there. Maybe i missed it, but can anyone comment on if they used the rear BBK too?

.

[bigjae1976]

Originally Posted by aus

Maybe i missed it, but can anyone comment on if they used the rear BBK too?

.

I would like to know that too. In my mind...that would make a significant difference.

[r53s65e90]

Originally Posted by aus

Maybe i missed it, but can anyone comment on if they used the rear BBK too?

.

There is no mention of the tears in the article. All data (prices, weights, dimensions) are for fronts only.

[r53s65e90]

Also, let me restate something I mentioned before a bit more clearly:

The brembo kit they tested is for all practical purposes equivalent to the E46 380 kit with the thinner rotor and the M caliper. The reason probably is that this kit is the only TUV approved kit and does not require the "Einzelabnahme" from TUV like PFC and AP (the only kits that they mention need this). You can also figure this out from the pictures of the rotors that don't have the McLaren fasteners.

Brembos still suck though. Just mentioning this detail for whomever thinks it is interesting.

[bigjae1976]

Originally Posted by r53s65e90

There is no mention of the tears in the article. All data (prices, weights, dimensions) are for fronts only.

Just tears from brembo owners

[r53s65e90]

Originally Posted by bigjae1976

Just tears from brembo owners

I have been crying rivers over here...

[rngrjag]

I'm sold; who has the best prices on Stoptechs? (ST60's for OEM Comp rims.)

[1MOREMOD]

Originally Posted by rngrjag

I'm sold; who has the best prices on Stoptechs? (ST60's for OEM Comp rims.)

I shopped around and found best deal with trinity.

[rngrjag]

Originally Posted by 1MOREMOD

I shopped around and found best deal with trinity.

Thanks, will check them out.

[dbyrd]

Originally Posted by 1MOREMOD

I shopped around and found best deal with trinity.

I'm looking for ST-60 as well. R1 Concepts has good prices.

Anyone know of seasonal sales?

[bigjae1976]

I've got the ST60 kit on the front. Regret not getting the ST40 so that I can run much cheaper 17" wheels/tires AND use cheaper pads and rotor discs.

[dbyrd]

Originally Posted by bigjae1976

I've got the ST60 kit on the front. Regret not getting the ST40 so that I can run much cheaper 17" wheels/tires AND use cheaper pads and rotor discs.

I've heard you say that several times, James. My only concern is the heating dispersion and stopping power after 30 minutes in 105 degree temps slowing for turn 12 at CoTA or turn 1 at TWS.

Anyone else think ST-40s are sufficient in the front?

[Richbot]

Originally Posted by dbyrd

I've heard you say that several times, James. My only concern is the heating dispersion and stopping power after 30 minutes in 105 degree temps slowing for turn 12 at CoTA or turn 1 at TWS.

Anyone else think ST-40s are sufficient in the front?

Me.

At some point you need to get more air to the brake system or you are just shifting the heat soak from the brakes to the tires. Does no good to have extra heat capacity in the brakes if the tires grease up anyway. If it's enough brake for a viper which acieves anout 20mph higher terminal speeds, its enough for an m3

[jritt@essex]

A couple of thoughts from an insider viewpoint:

• I don't speak German, but from what I can gather from the pics, numbers, and discussion, it looks like this article is based around track performance. My first question is: Why would they take a group of street big brake kits and test them on the racetrack, rather than evaluating each of the manufacturers' best available track brake kit (StopTech Trophy, AP Racing Competition Kit (either their Factory one or our Essex one), a Brembo GT-R kit, etc.)? I'm assuming it's because the BBK's in the article are the only ones that are currently TUV approved? Street performance and track performance are evaluated under an extremely different set of criteria. Street performance is about pedal feel, seamless ABS interaction, Noise/Vibration/Harshness, and cosmetics. Track performance is about fade resistance, disc, pad, and caliper temperatures, component weights, available pad options, pad and disc wear rates, iron disc replacement costs, wheel fitment, etc. Excelling in one arena doesn't typically mean being the top of the heap in the other. If you're going to look at track performance by brand, it would make sense to put each manufacturer's best foot forward for the competition.

• As others have mentioned, pads are a critical piece of the puzzle, and variable elimination is at the core of the scientific method. To make the comparison as apple-to-apples as possible, it definitely would have been best to run the same pads in all kits. I can understand why they didn't use the same pad compound in each kit, but it is a variable that does unfortunately impact the results rather dramatically. Anyone running one of these kits their M3 on a track in Germany can easily toss the pads that came with their kit and likely get Pagid race pads at a reasonable price (Pagid is a popular brand in that region). As such, it seems a bit silly to insist that the pads remain "as delivered." Yes, I know that the pads are considered part of the approved kit in Germany, but I also know that people will run what they need to run on the track.

• That said, the magazine was working with what they were given, within the as-delivered specs including TUV approval (which is crucial in Germany). I'm sure the magazine editors also didn't want to add to an already costly test by spending an additional $2400 to buy identical race compounds for all of the kits in the various shapes (6 kits x $400 per pad set). It still seems like a very big missed opportunity to me.

• Comparing a street or semi-street hybrid pad against a track pad is a big no-no. Their characteristics are dramatically different (see my article on How to Choose Brake Pads). The FM1000 that ships in a Brembo kit is a slightly milder version of Ferodo DS2500. Pagid RS29 is an endurance racing compound. They're not even remotely similar.

• As some others have mentioned, stopping distance is largely a function of tire choice. Using the same tires on all was an excellent choice. One would expect any solid aftermarket street BBK to have a similar or slightly better stopping distance than OEM under a one stop scenario. The Brembo results are definitely surprising in that regard. Again though, pad friction level when cold has an influence on this result, but the FM1000 pads in that kit should have good cold bite.

• Now I'm not sure if I'm reading the data correctly, but it looks like every brake kit tested, including OEM, had very little fade over 20 stops from 200-0 kmph. The 20th stop on each was roughly within a meter of their first stop distance. That means none of them, including stock, exhibited any noticeable fade. If I was analyzing the data for the article as presented, it would have been a single sentence article, "If you never plan to do anything more than 20 stops from 200 kmph, don't waste your money on a BBK!" Some of the kits showed a shorter 20th stop vs. the first, which is likely because the race pad compounds generate more mu with some heat in them.

• What they should have done first is to find the 'failure point' of the OEM system. If the OEM system wilted on the 27th stop from 200 kmph, adding 20 meters to the stopping distance, then from that point 'up' (more stops and/or from a higher speed) would have been the critical info to gather on the big brake kit stopping distances relative to stock and each other.

• To take this a step further…run each big brake kit until it wilts from overheating, be it pad fade or fluid fade. That would show how much torture each could take, and would give a better understanding of their value vs. the OEM brakes, their relative durability to each other, and a better approximation to the stresses inflicted upon your brakes at the track.

• Taking disc temps would have shown how cool the discs were running after the series of stops. This could have been done with a pyrometer at the end of the stop, or for more accuracy, on-board via a thermocouple with data-logging (very simple with today's data acquisition…pedal travel and pressure can also be measured in that manner). Disc operating temps are critical when evaluating the efficiency of a brake kit (how much air the discs flow), pad and disc wear rates, the impact on the caliper and brake fluid temps, and the resulting likelihood of boiling that fluid. Without temps, you don't really know which kit is working best or smartest, or which is likely to last longest.

• They could have taken a look at the discs in each kit after the test to evaluate heat checking/cracking, as well as pad wear (how many mm of pad remain, any taper, etc.). Again, that would give some great insight into how durable each kit is, and what a user could expect.

• The weight of separate components should have been measured. Two kits may weigh the same, but one may have far more thermal mass in the disc, while the other is toting around four extra, unneeded lbs. in the caliper. The complete corner weight doesn’t mean much without knowing where that weight is!

• How much do spare iron rings cost? How much do replacement race pads costs? Are there a lot of pad options for each kit? Does each kit fit the most common track wheels people are using? These are some of the most important questions when evaluating an aftermarket big brake kit.

Overall, I wouldn't go so far as to completely throw this evaluation under the bus, but I don't know how much valuable data actually lies within it. As far as I can tell we're looking at street big brake kits being tested for stopping distances under moderate usage conditions that don't even exceed the stock brake system's capacity. In such a case, feel and aesthetics will be the primary differences between kits, which are both subjective.

[s85e90]

Everyone here becomes hyper critical when they see results that they do not agree with simply put. I can change the pads in my stock brakes and make them great, but that wouldn't evaluate an "as bought" kit then would it? They did the right thing, and while we can improve upon individual components the data collected isn't bad.

[OC ///M]

Originally Posted by s85e90

People will always try to defend what they want the outcome to be irregardless of what the actual test produces. Funny

What's even funnier are people who say irregardless.



Thank you jritt@essex for your well-written post.

[s85e90]

Originally Posted by OC ///M

What's even funnier are people who say irregardless.



Thank you jritt@essex for your well-written post.

I guess ... You must have Brembos

[bigjae1976]

Originally Posted by s85e90

I guess ... You must have Brembos

Lol

[FormulaMMM]

Originally Posted by dbyrd

I've heard you say that several times, James. My only concern is the heating dispersion and stopping power after 30 minutes in 105 degree temps slowing for turn 12 at CoTA or turn 1 at TWS.

Anyone else think ST-40s are sufficient in the front?

I do. ST-40 with race pads (RS29s for me) up front and a race or even hybrid (stoptech sp) rear pad on the stock caliper is more than most will need. Been a great setup for me. Start with this setup and upgrade the rear if you find insufficient.