Official Fix for Shattered Brake Pistons

[pixelblue]

Originally Posted by Lubo

I do not know at the moment. I need to research this issue. Thing is my car is a lease, so I do not really feel like spending $500 on a rebuild as I need to do a return next March. At the moment buy out at the lease return is out of questions as my family grew last year and I need something bigger, fingers crossed for E90 M3.

Whatever I'll do I am definitely fabiricating some sort of cooling hose as this is clearly heat related. It also has to do with what track you drive at. I did 3 events at Monticello last year, and that track is hard on brakes. This modifications is a never ending battle. You improve in one area only to find shortcomings in another.

I hear you man. tough position if you have to return the car. I guess $500 would be cheaper than replacing the calipers. would be a shame to miss out the whole track season though. I got the titanium shims installed and I also bent the dust shield to get some more air in there. hoping I don't have to brake as hard with the R-comps since I will be able to take the turns at a faster speed

[Lubo]

Originally Posted by pixelblue

I hear you man. tough position if you have to return the car. I guess $500 would be cheaper than replacing the calipers. would be a shame to miss out the whole track season though. I got the titanium shims installed and I also bent the dust shield to get some more air in there. hoping I don't have to brake as hard with the R-comps since I will be able to take the turns at a faster speed

Yes but you will brake later and brake harder and track out faster. This will mean one more hot lap and in the end you are in the same boat

I try to take em apart in the next week and so. Maybe I will be able to just replace the boots and seals. I wasn't planning for any event till first week of May, but that might get pushed now couple of weeks.

[ScarecrowBoat]

I'm going to the track on friday and will be running EBC Yellow Stuff up front and stock in the rear. I guess we'll see how it goes...

[Lubo]

Originally Posted by maxnix

Ah, but the equation is F=mv*2, and the 135i is heavier, and more important, faster.

I can't argue about being faster but my 135 with full tank of gas and some junk in the trunk came in at 3450lbs, golf came in at 3270, but I can't recall how much gas was in it so not much difference there.

Originally Posted by niceworkbavaria

I'm going to the track on friday and will be running EBC Yellow Stuff up front and stock in the rear. I guess we'll see how it goes...

I ran EBC all the way around, didn't have problem with fade on the track in the 20minute sessions. I also had the Motul RBF600 fluid in. Have fun out there

[DriveHard]

Originally Posted by Lubo

I can't argue about being faster but my 135 with full tank of gas and some junk in the trunk came in at 3450lbs, golf came in at 3270, but I can't recall how much gas was in it so not much difference there.




I ran EBC all the way around, didn't have problem with fade on the track in the 20minute sessions. I also had the Motul RBF600 fluid in. Have fun out there

Lubo.. did you run EBC yellow front and back ??? how about noise ??

[spk74]

my last physics class was more than a decade ago, but I believe:

f = m*a , a=dv/dt ==> f=m*dv/dt

kinetic energy = m*v^2

work = force * distance [=] energy

(braking work) = (loss in kinetic energy)
= m2*v2^2 - m1*v1^2
= m(v2^2-v1^2)
= (braking force)*(braking distance)

hence,

(braking force) = m/(braking distance)*(v2^2-v1^2)

[ScarecrowBoat]

nerds

[Lubo]

U lost me lol

[larryn]

Lubo, those look okay to me. As was said, the seals tend to get brittle and can get damaged. Mine looked nothing like those. All of my pistons were either totally shattered, missing or a stack of porcelain shards.

I know of a few Time Attack racers on this board who use the mentioned setup from the first post, but to do the whole system, it's costly.

I wound up looking at the cost of doing this for front and rear, plus pads + sensors (+$2k), and then saw Dan@United selling off the BMW performance kit with rotors, pads, sensors, and front and rear calipers for $799, and did that last Fall. I went with the Phoenix Yellow painted kit. Money talks.

My next track time will include ducting, and a thorough bedding of the new (and more aggressive that HP+) pads. I was running new HP+ pads that I don't think were completely bedded, and I had minor glazing, which lead to even more heat. Glazing can be a serious and dangerous issue.

More air and good fluids are your friends on the stock calipers.

[Lubo]

Originally Posted by larryn

Lubo, those look okay to me. As was said, the seals tend to get brittle and can get damaged. Mine looked nothing like those. All of my pistons were either totally shattered, missing or a stack of porcelain shards.

I know of a few Time Attack racers on this board who use the mentioned setup from the first post, but to do the whole system, it's costly.

I wound up looking at the cost of doing this for front and rear, plus pads + sensors (+$2k), and then saw Dan@United selling off the BMW performance kit with rotors, pads, sensors, and front and rear calipers for $799, and did that last Fall. I went with the Phoenix Yellow painted kit. Money talks.

My next track time will include ducting, and a thorough bedding of the new (and more aggressive that HP+) pads. I was running new HP+ pads that I don't think were completely bedded, and I had minor glazing, which lead to even more heat. Glazing can be a serious and dangerous issue.

More air and good fluids are your friends on the stock calipers.

It is hard to see in some pictures as I took em with a phone. Most of the seals are torn. I should have taken pictures before I compressed them in as it was more apparent then. I will have someone more experienced look them over in more detail. I am just worried about shattering the pistons at later date, especially since I upgraded to camber plates and 255 up front. Car can be driven much harder now, which will only result in more heat and possibly causing more damage.

On another note are you guys doing any events @ Mt. Tremblant this year? I would love to hit that track up while the wifey stay at the resort. This way there is less complaining about wasting money while driving in circles.

[bradford]

Originally Posted by Amalfitano

I don't know if Autocross generates enough heat to have this issue since we don't even approach fade, but i could be wrong.

LOL. No dude, you're fine.

[Addict...Nah Im A Junkie!]

Originally Posted by spk74

my last physics class was more than a decade ago, but I believe:

f = m*a , a=dv/dt ==> f=m*dv/dt

kinetic energy = m*v^2

work = force * distance [=] energy

(braking work) = (loss in kinetic energy)
= m2*v2^2 - m1*v1^2
= m(v2^2-v1^2)
= (braking force)*(braking distance)

hence,

(braking force) = m/(braking distance)*(v2^2-v1^2)

You really need to get latex to type that stuff in man, that's just painful to read.

[adrean8j]

Originally Posted by Lubo

On another note are you guys doing any events @ Mt. Tremblant this year? I would love to hit that track up while the wifey stay at the resort. This way there is less complaining about wasting money while driving in circles.

Always we have to make that compromise don't we?

[larryn]

Originally Posted by Lubo

On another note are you guys doing any events @ Mt. Tremblant this year? I would love to hit that track up while the wifey stay at the resort. This way there is less complaining about wasting money while driving in circles.

I think I'm going up for the Boston Chapter's 'Bimmers Across the Border' event this year (8/26-28). I didn't make it last year. I take the wife usually too, and get a nice room at Le Sommet des Nieges.

They have a decent zipline/aerial obstacle course near the top of the village too. But the goodie is La Diable, brew pub, smack in the middle of the resort village. Surprisingly decent beer.

[Lubo]

Originally Posted by larryn

I think I'm going up for the Boston Chapter's 'Bimmers Across the Border' event this year (8/26-28). I didn't make it last year. I take the wife usually too, and get a nice room at Le Sommet des Nieges.

They have a decent zipline/aerial obstacle course near the top of the village too. But the goodie is La Diable, brew pub, smack in the middle of the resort village. Surprisingly decent beer.

Awesome, I think I will see you there. Looks like registration opens in 3 days. I see it is the 12th time you guys are heading up there. Does the event usually sell out fast or do I have couple more months to register?

[larryn]

Originally Posted by Lubo

Awesome, I think I will see you there. Looks like registration opens in 3 days. I see it is the 12th time you guys are heading up there. Does the event usually sell out fast or do I have couple more months to register?

We struggled to fill it last year, but that only means that we get more track time and fewer cars to get in the way.

[uberschnell]

Has anyone actually done this fix?

[scorcherjf]

Has anyone actually fixed theirs yet or are people just buying new BBKs? I fear mine look like this.. will have to check.

[Focusedintntions]

Has anybody used this?? be nice to see a review...

[larryn]

Some of the racers have done this exact fix... successfully. I got the info from them.

[Focusedintntions]

Thanks for the response Larryn. Somebody should sticky this as I have a feeling there will be several of us eventually doing this.

[xerox445]

has anyone actually done this with the machined pistons?