[ThereCanBeOnly1]

I'm in the process of selling a car that I didn't research enough before buying, and I don't want to make that mistake again.

I plan to get a car that I will mostly use for DEs for a couple of hopefully awesome years. The M2 is one of the cars I am seriously considering.

I've read that heat-soak on long, over 90' days is possible. That is a concern for me as I am in South Florida. In the summer you can see where that is leading. So I will need to keep in mind $2k or so for upgraded cooling stuffs (oil, radiator). And speaking of heat, brakes. How are all of you doing with the stocks? I've caused many calipers to fail lately, and I don't think I am being too bad on them- its just heavy cars and very high temps. I see there are no readily available kits, let alone factory options. Is the accepted method for brake cooling the generic A-Arm duct and some other generic backing plate retrofitted? I'd want to do something.

What else am I missing? Any Achilles heel or annoyance like bad shifting, engine failures, cracking shock towers, crying babies, etc?

[ZM2]

If you keep engine power stock and you’re doing 20-30min sessions, OEM cooling should be fine. Add a little boost and you’ll need a larger IC. Add more boost or if you’re doing over 30min sessions, a larger radiator then maybe oil cooler will likely be needed.

As for brakes, this seems driver dependent. Many of the guys are OK with just track fluid and pads, but most everyone with more than 5 track days experiences caliper paint change from excessive heat. My calipers are now almost black (25 days).

Unfortunately, I’ve also trashed an OEM caliper that now has a sticking piston, so I’m waiting for PFC’s BBK to come out. I’ve had the Porsche spoiler cooling for a while, which helped, but my braking style is much harder than most and my OEM brakes have paid the price.

I think BMW knows the brakes on the M2 suck for hard track use. Just look at the M2 CS. Not much more power, but much bigger brakes. If I had to do it over again, I’d start with a front BBK before going on track and save all the headache and caliper failure I’ve experienced.

[horsepower_and_hounds]

Originally Posted by ZM2

If you keep engine power stock and you’re doing 20-30min sessions, OEM cooling should be fine. Add a little boost and you’ll need a larger IC. Add more boost or if you’re doing over 30min sessions, a larger radiator then maybe oil cooler will likely be needed.

As for brakes, this seems driver dependent. Many of the guys are OK with just track fluid and pads, but most everyone with more than 5 track days experiences caliper paint change from excessive heat. My calipers are now almost black (25 days).

Unfortunately, I’ve also trashed an OEM caliper that now has a sticking piston, so I’m waiting for PFC’s BBK to come out. I’ve had the Porsche spoiler cooling for a while, which helped, but my braking style is much harder than most and my OEM brakes have paid the price.

I think BMW knows the brakes on the M2 suck for hard track use. Just look at the M2 CS. Not much more power, but much bigger brakes. If I had to do it over again, I’d start with a front BBK before going on track and save all the headache and caliper failure I’ve experienced.

I find this whole M2 brake debate very interesting since they are identical as the F80/82. Is the issues with the M2 due to them seeing more track days then M3/4's? I mean you would think a slightly slower lighter car would be easier on the brake system then the bigger heavier more powerful package. Jus a curious question...... Guess most M3/4's are not track cars

[ZM2]

Originally Posted by m2ruder

I find this whole M2 brake debate very interesting since they are identical as the F80/82. Is the issues with the M2 due to them seeing more track days then M3/4's? I mean you would think a slightly slower lighter car would be easier on the brake system then the bigger heavier more powerful package. Jus a curious question...... Guess most M3/4's are not track cars

I also wondered the same question. I assumed it was bc the packaging on the M2 was tighter and less air was making it thru the brakes, but I don’t think that’s it.

I’ve heard similar issues with the M3/4. Some guys have no issues with the brakes, some have changing caliper coloration, and some destroy the calipers.

I think it just comes down to how hard one is driving the car and their braking style.

[MR_M2]

Fuel starvation: M2 suffers from fuel starvation issue at the track which puts the car in limp mode. It happens when you have less than half a tank of gas left in the car. My friend's M4 did the entire day (5 sessions) in a single tank of gas. I had to refuel every 2.

Limp/comfort mode because of low tire pressure: If you leak out hot air from the tire hoping it goes back up on the track then beware- Once the tire cools down in between your sessions and the tire pressure drops below 32psi, car goes into limp/comfort mode. It DOES NOT go back to normal on the track even if the tire pressure goes up. Tip: Make sure you don't drop your hot tire pressure below 38.

Brake cooling ducts: I haven't personally felt the lack of braking, but it does soften up a bit towards the entire of session (on track pads). Some people have Jerry-rigged a custom cooling pipe which you can look up.

[ZM2]

Originally Posted by MR_M2

Fuel starvation: M2 suffers from fuel starvation issue at the track which puts the car in limp mode. I happens when you have less than half a tank of gas left in the car. My friend's M4 did the entire day (5 sessions) in a single tank of gas. I had to refuel every 2.

Limp/comfort mode because of low tire pressure: If you leak out hot air from the tire hoping it goes back up on the track then beware- Once the tire cools down in between your sessions and the tire pressure drops below 32psi, car goes into limp/comfort mode. It DOES NOT go back to normal on the track even if the tire pressure goes up. Tip: Make sure you don't drop your hot tire pressure below 38.

Brake cooling ducts: I haven't personally felt the lack of braking, but it does soften up a bit towards the entire of session (on track pads). Some people have jerry-rigged a custom cooling pipe which you can look up.

True about fuel starvation. The Dinan LPFP mod kit fixed that for me and is relatively cheap.

On tire PSI and TPMS, most of us can drop pressures to 26/27 without limp mode. Still requires resetting the TPMS before leaving the pits, tho. You can run without sensors and still run DSC off, but throttle and steering will have Comfort mode feel.

[ThereCanBeOnly1]

Oh man that tire pressure issue is obnoxious. That's computers run wild. Surprised nobody has made a simulator to trick the car into staying out of comfort mode. Good to know.

So wait- when I run track wheels car will go into comfort mode unless I also get a second set of tpms?!

[ThereCanBeOnly1]

Just looked up the dinan fuel pump- the price is 200 so no big deal, but the assembly instructions have a lot of steps. That seems like a job I might need therapy after, but these are the things we deal with I suppose

[ZM2]

Originally Posted by ThereCanBeOnly1

Oh man that tire pressure issue is obnoxious. That's computers run wild. Surprised nobody has made a simulator to trick the car into staying out of comfort mode. Good to know.

So wait- when I run track wheels car will go into comfort mode unless I also get a second set of tpms?!

Without TPMS sensors you can run in any traction mode, but steering and throttle response will be limited to Comfort. Doable on an MT car, but super slow shifts in a DCT car.

Or, you can have TPMS coded off and the car will use wheel speed to look for pressure drop. You lose temp and pressure readout in idrive, but you can start with any pressure you want and it won’t impact steering/throttle feel.

Personally, I run with sensors and start with 27psi. Pressure will get a little high towards the end of a long session (36-38psi), but I prefer not to have to fight or work around the TPMS system.

[PrimeBMW]

Originally Posted by MR_M2

Fuel starvation: M2 suffers from fuel starvation issue at the track which puts the car in limp mode. It happens when you have less than half a tank of gas left in the car. My friend's M4 did the entire day (5 sessions) in a single tank of gas. I had to refuel every 2.

Limp/comfort mode because of low tire pressure: If you leak out hot air from the tire hoping it goes back up on the track then beware- Once the tire cools down in between your sessions and the tire pressure drops below 32psi, car goes into limp/comfort mode. It DOES NOT go back to normal on the track even if the tire pressure goes up. Tip: Make sure you don't drop your hot tire pressure below 38.

Brake cooling ducts: I haven't personally felt the lack of braking, but it does soften up a bit towards the entire of session (on track pads). Some people have Jerry-rigged a custom cooling pipe which you can look up.

What a pain......

[emdeuce]

Stock brake pads. However it depends on your track and if there are alot of high speed braking zones. I currently have no problems with fade on 1-2 of my local tracks, while there are other tracks where I do.

[MagnusT]

I'm with ZM2 on the brakes issues. My calipers are still in fine shape apart from being dark brown. Duh! I have the Porsche GT3 a-arm brake scoops. They help but I'm at the edge in temps on longer stints.

[gsrbri]

I had 30 track days on my 2015 M4 and the front calipers are aqua-marine color. My M2 only has 2 track days at LRP (PFC08 pads) and they haven't changed color yet. I'd love to have the Radical AP racing brake kit (open pad access remains, which is awesome) bit they don't have a rear kit avail.

[ZM2]

Originally Posted by gsrbri

I had 30 track days on my 2015 M4 and the front calipers are aqua-marine color. My M2 only has 2 track days at LRP (PFC08 pads) and they haven't changed color yet. I'd love to have the Radical AP racing brake kit (open pad access remains, which is awesome) bit they don't have a rear kit avail.

I believe Essex has the rear kit available. I’m planning on starting with just the front and see how the car performs and if the rear OEM holds up—mine are already black, so I might as well trash them.

[M2joey]

Originally Posted by m2ruder

I find this whole M2 brake debate very interesting since they are identical as the F80/82. Is the issues with the M2 due to them seeing more track days then M3/4's? I mean you would think a slightly slower lighter car would be easier on the brake system then the bigger heavier more powerful package. Jus a curious question...... Guess most M3/4's are not track cars

It is an interesting debate. I remember when the F* M3/M4 came out. A number of reviews said the stock brakes could be better, some said not that good, etc. The feedback has pretty much been the opposite for the M2.

One thing that comes to mind is how amazing ABS is in the M2! It is almost impossible to detect when you are in ABS under heavy braking. Easier to tell on a slightly wet track. Not being aware you are in ABS does a few things - makes all-around braking seem better, allows you the confidence to brake later and harder, and generates more heat. I wonder if this might be part of the difference. The M2 may also have slightly better cooling dynamics. These are the types of questions we need to get BMW to answer.

Personally, I am very happy with the brakes. I felt they performed great this year, and many others who have been in my M2 have said the same. I did have a few moments later in the year where I did ask too much, and they were just too hot. The calipers are fine, did change color. I do need new front rotors to start the year although that is another story.

Again, as others has mentioned, a lot of this has to do ultimately with your braking technique.

[Anthony1s]

Anyone have pictures of their calipers changing color? I'm really interested to see what they look like.

[ZM2]

Originally Posted by Anthony1s

Anyone have pictures of their calipers changing color? I'm really interested to see what they look like.

I’ve got some black ones in a box at home that my AP’s replaced. No pics, but they’re dark gray/black. Looks like burnt paint.

[Jcp135]

Anybody tried this two piece rotors? They are better dealing with heat which will be transfer to the calipers, if it works will be a cheaper solution than BBK.
I had installed in my carrera S, will have first track day March 10.

http://www.racingbrake.com/RB-Two-pi...bmw-irk-13.htm

[ZM2]

Haven’t tried them, but it seems the brake heat issue is more about pad size and calipers on the M2.

[ZPrime]

Friends don't let enemies buy RacingBrake.
Made-in-China to an absolute low-end budget. Catastrophic failures are not uncommon, with the company playing he-said-she-said games with the customer and refusing to honor warranties and all sorts of other garbage.

I'd stick to a major braking company; it is only one of the most important parts of the car's safety systems...

[dvas]

Originally Posted by isjoey

It is an interesting debate. I remember when the F* M3/M4 came out. A number of reviews said the stock brakes could be better, some said not that good, etc. The feedback has pretty much been the opposite for the M2.

One thing that comes to mind is how amazing ABS is in the M2! It is almost impossible to detect when you are in ABS under heavy braking. Easier to tell on a slightly wet track. Not being aware you are in ABS does a few things - makes all-around braking seem better, allows you the confidence to brake later and harder, and generates more heat. I wonder if this might be part of the difference. The M2 may also have slightly better cooling dynamics. These are the types of questions we need to get BMW to answer.

Personally, I am very happy with the brakes. I felt they performed great this year, and many others who have been in my M2 have said the same. I did have a few moments later in the year where I did ask too much, and they were just too hot. The calipers are fine, did change color. I do need new front rotors to start the year although that is another story.

Again, as others has mentioned, a lot of this has to do ultimately with your braking technique.

How are you determining you need new rotors? Are you measuring thickness, judging by the lip, looking for cracks or something else?

I've got a good number of days on my fronts but they seem fine.

[M2joey]

Originally Posted by dvas

How are you determining you need new rotors? Are you measuring thickness, judging by the lip, looking for cracks or something else?

I've got a good number of days on my fronts but they seem fine.

The fronts seems to be worn more on the around the inner 40% of the rotor vs the outer part. The rears were still ok. I did put new rotors on all-around as I also did not want to mix brake pad compounds. I went from PFC-08s to PFC-11s, maybe a little overkill.

Measuring would of course be one of the correct ways to go about this. Cracking to some extent is normal.