Let's talk brakes...

[mikeo]

You've also convinced me. But I'm already a 135i whore.

[Drillslinger]

Originally Posted by mikeo

But I'm already a 135i whore.

Me too dude Provided the price doesn't creep too close to the 40k mark

[imported_MPower]

Originally Posted by eMINI

Good point! I'll go 90% with you on this one. I agree that the tires are crucial (being the interface to the pavement and all that). I'd also agree that big brake kits often don't provide any significant improvement on a single stop over a simple pad upgrade. But their ability to handle more heat, as in a track session or other repeated hard use, is where they really shine.

I guess I only take issue with the idea that engaging the ABS is the shortest stopping technique. For many people it may well be, but if the driver can modulate the brakes effectively, keeping the tires right at the threshold of lockup, stopping distances are measurably shorter than what ABS can accomplish. Threshold braking may be more easily and consistently acheived with the multi-piston, fixed caliper system on the 135 coupe. If so, this is a worthwhile improvement and not a marketing gimmick.

I think, if nothing else, I've convinced myself.

The tire grip limiting braking performance was the logic the M Division used to justify using single piston brakes on the M5 and M6. In their defense, I have heard good things about the M5's brakes (equally, I have heard bad things about brake fade) from people like Tiff Needell. Still, I dont think there is any question that a good 6-piston setup will last longer on a track than a good single piston setup.

[LonghornTX]

Let us not forget that their appears to be brake cooling ducts in the front valance of the 135i (hopefully attached to some NACA ducts).

This car has a very serious braking setup, stock. It makes me very happy, not only for the sheer mechanical efficiency they will provide, but also the depth of focus BMW took this car to. If the brakes are this good (to me, brakes are too often overlooked), I can only imagine what the handling will be like....

[ibeam81]

Originally Posted by LonghornTX

Let us not forget that their appears to be brake cooling ducts in the front valance of the 135i (hopefully attached to some NACA ducts).

This car has a very serious braking setup, stock. It makes me very happy, not only for the sheer mechanical efficiency they will provide, but also the depth of focus BMW took this car to. If the brakes are this good (to me, brakes are too often overlooked), I can only imagine what the handling will be like....

The 135i keeps sounding better and better, but all the M bits have me a little concerned regarding the longterm maintenance costs for the car. Fortunately, it won't be an issue initially while the car is under warranty.

Does anyone else have any concerns over this? If the 135i is as good as it's looking to be, then I would like to keep this car a very long time.

[LonghornTX]

Originally Posted by ibeam81

The 135i keeps sounding better and better, but all the M bits have me a little concerned regarding the longterm maintenance costs for the car. Fortunately, it won't be an issue initially while the car is under warranty.

Does anyone else have any concerns over this? If the 135i is as good as it's looking to be, then I would like to keep this car a very long time.

I do as well. I plan on keeping this car for a long time......

[BForbes]

I know myself, i never miss an opportunity to upgrade..to an M1 that is.

[mikeo]

Look at the E36 M3. It sold, oh, maybe 75K units in the U.S. over its production run at ~$45K. Granted it is less technically complex than current era vehicles, but it is not really expensive to maintain. The 135i has the potential to sell many more units than the E36 M3, so let's hope the volume produced will soften the cost of maintenance.

[eMINI]

You've convinced me. But I'm already a 135i whore. :wink:

[imported_MPower]

Originally Posted by LonghornTX

Let us not forget that their appears to be brake cooling ducts in the front valance of the 135i (hopefully attached to some NACA ducts).

According to the US Press Release, those are brake cooling ducts.

[mateo]

Very nice to see upgraded, or better standard brakes available. These breaks will be on-par w/what I'd expect.

-Mateo

[Klinn]

Originally Posted by ibeam81

Does anyone else have any concerns over this? If the 135i is as good as it's looking to be, then I would like to keep this car a very long time.

The only thing that concerns me is long-term reliability of the turbos and associated bits close to their heat.

Will definitely want to pop the hood after a quick Solo2 run. :biggrin:

[335i=:)]

Originally Posted by Klinn

The only thing that concerns me is long-term reliability of the turbos and associated bits close to their heat.

Will definitely want to pop the hood after a quick Solo2 run. :biggrin:

Klinn, out of curiosity, how does your m-tech suspension compare to a regular sport suspension in your experiecnce with your car? Haveyou ridden in both?

The 135i coming with m-springs makes me wonder what the difference is.

[Klinn]

Originally Posted by 335ito135i

Klinn, out of curiosity, how does your m-tech suspension compare to a regular sport suspension in your experiecnce with your car? Haveyou ridden in both?

Yup, I tried them back-to-back when buying the car (used). I take part in some Solo2 events, so I'm used to pushing a car somewhat closer to its limits, and fortunately the dealership was located near an under-construction suburb, so there were a couple of empty newly-paved corners to test it on. I just made sure to warn the salesman that I was going to try cornering "briskly". :biggrin:

On a purely subjective level, it felt like the body roll was halved. That's a gross approximation and in no way an objective measurement, just the "feel". It's not as buttoned down as the M3, but the ride isn't as punishing either. We have lots of frost heaves up here in the great white north, so it was a good compromise for me.

The M-Tech suspension is basically what ended up being used later on the 330 ZHP "Performance" model, although my earlier package has 17" wheels instead of 18"s.

[321]

Originally Posted by 335ito135i

I bet we can just replace the rotors and brake lines/fluid and get some serious results.

You mean pads and brake lines/fluid. The rotors will be fine. Pads fade before the rotors warp. Remember that pad deposits are what is perceived as rotor warp 95% of the time. If you are a road course guy you wont want cross-drilled, if anything you want slotted. Reasons being is the rotor is a heat sink and it needs mass in order to take the heat. Cross-drilling takes away from that mass. So w/o getting too technical... road course=Slotted FTW autocross should be fine with cross-drilled but you still have to worry about cracks.

[bradford]

Originally Posted by eMINI

Nobody appreciates the value of great brakes more than I do, but if they'd just shave a few more pounds off this baby... the trick brakes wouldn't be needed. Or, they could do both! $35K supercar:roundel:

Ehhhhhhhhhh, my 2005 Mini Cooper S needed Stoptechs and it only weighed under 2700 pounds.

[grant]

Originally Posted by bradford

Ehhhhhhhhhh, my 2005 Mini Cooper S needed Stoptechs and it only weighed under 2700 pounds.

Yeah, and my 73 911 racer is only 1,890 lbs and I needed to upgrade to Porsche Turbo brakes (Brembo 4-piston).

The amount of heat generated during braking is proportional to the weight of the car (twice as heavy means double the heat), but it is also proportional to the square of the velocity (so, if you're going twice as fast at the braking zone, it produces 4 times the heat).

So, a fast car is always going to need big brakes, just not as big as a fast & heavy car...

[grant]

One other item - people keep talking about the 6-piston brakes holding up better on the track. Don't be confused. Better calipers only mean they can squeeze harder (and more evenly on the pads), so changing to better calipers will likely create as much or more heat and cause fade to occur just as soon or sooner. The real important thing is to have big rotors (lots of steel - large diameter and thick). Cooling vias air ducting and ventilated rotors is important too.

Brembos are great for pedal feel though (if used with the proper master cylinder and not overly assisted)!

[bradford]

Originally Posted by grant

The real important thing is to have big rotors (lots of steel - large diameter and thick). Cooling vias air ducting and ventilated rotors is important too.

Right but IIRC from the literature the rotors are at least 332mm - that will be plenty for a 3250 pound car with 50/50 weight balance.

EDIT: They're 338mm. That will be plenty IMHO, considering that the 135i deletes the foglights in order to accomodate brake ducting. Now I jus hope Hawk makes HT-10s or DTC70s in 135i fitment.

Originally Posted by grant

Brembos are great for pedal feel though (if used with the proper master cylinder and not overly assisted)!

I've seen people talk about Brembos on the 135i a lot. I've never seen BMW use a Brembo caliper before, and I didn't see it in any of the press releases. Has this been confirmed?

[inTgr8r]

Originally Posted by bradford

Right but IIRC from the literature the rotors are at least 332mm - that will be plenty for a 3250 pound car with 50/50 weight balance.

EDIT: They're 338mm. That will be plenty IMHO, considering that the 135i deletes the foglights in order to accomodate brake ducting. Now I jus hope Hawk makes HT-10s or DTC70s in 135i fitment.
......
..

^+1
There's no point increasing rotor size unnecessarily....
you'd just be increasing unsprung weight, w/o getting anything in return.

[grant]

Originally Posted by inTgr8r

^+1
There's no point increasing rotor size unnecessarily....
you'd just be increasing unsprung weight, w/o getting anything in return.

Absolutely true. However, the very thin rotors on the 135 can be made to fade with hard track use and track tires, I'm fairly certain.

It's a difficult balance to choose a rotor that isn't too heavy for the road but heavy enough for the track.

I think the track junkies will want/need to upgrade to something bigger (especially with extra boost giving close to 400hp/400TQ)

[grant]

Originally Posted by bradford

EDIT: They're 338mm. That will be plenty IMHO, considering that the 135i deletes the foglights in order to accomodate brake ducting. Now I jus hope Hawk makes HT-10s or DTC70s in 135i fitment.

What's the width though? Most Brembos are 34mm wide in that diameter - I think these are in the mid-high 20's - BIG diffference