Any recommendation of aftermarket steel rotors on stock calipers?

[BetrayMyWord]

I tracked my 19' M4 about 20 times a year and my home track (Laguna Seca) demands a lot from brakes.

Currently my brake system is somewhat stock-ish, just with PFC08 brake pads (has seen 3 track days) and Castrol SRF (flushed 4 track days ago). Over the weekend with PCG I boiled my brake fluid coming OUT of T2 (130->40mph) - yeah it was my pure luck that it did not happen at the entry of T2. It was a hot weekend - but it still caught me with surprise considering the relatively fresh fluid I had.

After some research on the forum, I see that going to BBK might be an once and for all approach; but before going to this expensive route, I would like to know whether I could simply upgrade my rotors to have better brake cooling and brake consistency.

BTW I am not sure about installing brake cooling duct on my car... not a DIY guy myself.

[fanatic1]

Originally Posted by BetrayMyWord

I tracked my 19' M4 about 20 times a year and my home track (Laguna Seca) demands a lot from brakes.

Currently my brake system is somewhat stock-ish, just with PFC08 brake pads (has seen 3 track days) and Castrol SRF (flushed 4 track days ago). Over the weekend with PCG I boiled my brake fluid coming OUT of T2 (130->40mph) - yeah it was my pure luck that it did not happen at the entry of T2. It was a hot weekend - but it still caught me with surprise considering the relatively fresh fluid I had.

After some research on the forum, I see that going to BBK might be an once and for all approach; but before going to this expensive route, I would like to know whether I could simply upgrade my rotors to have better brake cooling and brake consistency.

BTW I am not sure about installing brake cooling duct on my car... not a DIY guy myself.

No doubt it was hot down here at Fontana/auto club speedway as well: 116°F.

No personal experience, but I’ve heard good things about Girodisc rotors.

BBK was the best investment I’ve made so far on this platform. It completely eliminates the concern about brake fade at a track like Laguna. The AP Essex 9668 kit allows for 25 mm pads, which do last quite a bit longer.

Considering adding the rear kit for brake balance and to even out temperature.

Hopefully see you at Laguna in October.

[MyFragileHalogen]

If you have base M4 without tune, you might be able to get away with 2 piece rotors and brake shield removal. As I posted before I am testing out Racingbrake rotors and they perform great. Later this month I will be doing my brake-heavy home track with stickier R1 tires and be able to provide some feedback.

[BetrayMyWord]

Originally Posted by fanatic1

No doubt it was hot down here at Fontana/auto club speedway as well: 116°F.

No personal experience, but I’ve heard good things about Girodisc rotors.

BBK was the best investment I’ve made so far on this platform. It completely eliminates the concern about brake fade at a track like Laguna. The AP Essex 9668 kit allows for 25 mm pads, which do last quite a bit longer.

Considering adding the rear kit for brake balance and to even out temperature.

Hopefully see you at Laguna in October.

Thanks for reminding me of Girodisc! With it I found a useful post not long ago (https://f80.bimmerpost.com/forums/sh....php?t=1744940).

Are you running with stock rotor & caliper at the rear then?

Hope to see you again, too. I might go with SpeedSF, not with Speed District which has an insanely priced track weekend on 17/18th...

[BetrayMyWord]

Originally Posted by MyFragileHalogen

If you have base M4 without tune, you might be able to get away with 2 piece rotors and brake shield removal. As I posted before I am testing out Racingbrake rotors and they perform great. Later this month I will be doing my brake-heavy home track with stickier R1 tires and be able to provide some feedback.

Definitely looking forward to your feedback. My only concern with the removal of the dust shields is the proximity of rotors & rubber bushings; whereas AP/Essex recommends it that way I think it is OK tho.

[SYT_Shadow]

Originally Posted by BetrayMyWord

Definitely looking forward to your feedback. My only concern with the removal of the dust shields is the proximity of rotors & rubber bushings; whereas AP/Essex recommends it that way I think it is OK tho.

Definitely remove the heat shields. I haven't had any issues in the F8X or E9X platform and rubber bushings without them.

[NYG]

Remove those dust shields asap. They trap so much heat.

Also, I don't really think the stock rotors are too problematic. The caliper is the shitty part.

[fanatic1]

Originally Posted by BetrayMyWord

Thanks for reminding me of Girodisc! With it I found a useful post not long ago (https://f80.bimmerpost.com/forums/sh....php?t=1744940).

Are you running with stock rotor & caliper at the rear then?

Hope to see you again, too. I might go with SpeedSF, not with Speed District which has an insanely priced track weekend on 17/18th...

Wow, Speed District is certainly insanely priced - unlimited sound folks must be willing to pay.

Will look into SpeedSF, thanks.

[dvq]

Originally Posted by fanatic1

Wow, Speed District is certainly insanely priced - unlimited sound folks must be willing to pay.

Will look into SpeedSF, thanks.

Yeah there's a couple clubs out there that cater to exotics cars and in general drivers who don't want many other drivers on the course to either slow down lap times or pose as a risk.

Some of the cheaper groups it's not uncommon to see 20-30 cars in a single run group while these other clubs might have 5-10 in a run group. I've seen some down as low as 3 cars.

Exclusive Track Days is another one of the more exclusive kinds -- just loook at their lap time requirements for run groups.

https://etd.trackrabbit.com/event/de...eca-2020-11-21

[fanatic1]

Originally Posted by dvq

Yeah there's a couple clubs out there that cater to exotics cars and in general drivers who don't want many other drivers on the course to either slow down lap times or pose as a risk.

Some of the cheaper groups it's not uncommon to see 20-30 cars in a single run group while these other clubs might have 5-10 in a run group. I've seen some down as low as 3 cars.

Exclusive Track Days is another one of the more exclusive kinds -- just loook at their lap time requirements for run groups.

https://etd.trackrabbit.com/event/de...eca-2020-11-21

Last summer with speed district there was a total of 17 cars at Laguna, it was like a private track day.

Exclusive is fantastic, with a narrow range of lap times, you don’t have those ridiculous closure rates coming up on somebody turning lap times 20 seconds slower, but not cheap.

[SYT_Shadow]

I love those track time requirements. It would make my life so much easier

R (Race Car): open passing, very low car count. Only for cars under 1:37 lap time
A: Open passing, lap time sub 1:37 to 1:42
B: Point-by passing and open passing the straights, lap time 1:42 and slower

[M3SQRD]

Originally Posted by SYT_Shadow

I love those track time requirements. It would make my life so much easier

R (Race Car): open passing, very low car count. Only for cars under 1:37 lap time
A: Open passing, lap time sub 1:37 to 1:42
B: Point-by passing and open passing the straights, lap time 1:42 and slower

I sure hope those aren’t VIR full course times! Everyone would be in the B group unless you owned a prototype LMP1

[MyFragileHalogen]

A Group
Open passing, lap time sub 1:42 to 1:37

ETD member: $599.00

Guest Rate: $699.00

B Group
Point-by passing and open passing the straights, lap time 1:42 and slower

ETD member: $599.00

Guest Rate: $699.00

R (Race Car) Group
Open passing, very low car count, lap times under 1:37

ETD member: $999.00

Guest Rate: $1,100.00

[SYT_Shadow]

Originally Posted by M3SQRD

I sure hope those aren’t VIR full course times! Everyone would be in the B group unless you owned a prototype LMP1

Hahaha not at all! those are Laguna Seca times

[M3SQRD]

Originally Posted by SYT_Shadow

Hahaha not at all! those are Laguna Seca times

Glad to hear...I didn’t see lap times listed in any posts and didn’t notice the link which contained the Laguna Seca run group lap times.

[BetrayMyWord]

I ordered and installed Girodisc two-piece at the front.

Besides the rotors, I also replaced my OEM brake lines (20 track days on them...) with Goodridge SS brake lines.

Overall my brake pedal does feel better than before; the initial bite's improved a bit.

[ATX_M3]

Do you notice any improvement with reduced fade under high temps? I'm looking at Girodisc for my HPDEs @ COTA once I need to swap out my OEM rotors...

[MyFragileHalogen]

I am definitely happy with my two piece rotors as well. Done 3 dry days and 1 wet day and it only wore like 4mm of DS1.11, with my cheap ATE type 200 fluid still feeling fresh. Didn't get to try at home track demanding braking to the metal but I think at least it will be fine at other 2 tracks (RMP and ORP). Definitely a happy getaway option in my desperate (?) cost saving, until now I ended up with a whooping ~$9k quote (parts/install/setup and all that) for MCS 2ways that makes me consider selling my soul prior next season.

[fanatic1]

Originally Posted by MyFragileHalogen

I am definitely happy with my two piece rotors as well. Done 3 dry days and 1 wet day and it only wore like 4mm of DS1.11, with my cheap ATE type 200 fluid still feeling fresh. Didn't get to try at home track demanding braking to the metal but I think at least it will be fine at other 2 tracks (RMP and ORP). Definitely a happy getaway option in my desperate (?) cost saving, until now I ended up with a whooping ~$9k quote (parts/install/setup and all that) for MCS 2ways that makes me consider selling my soul prior next season.

$9k? Even with remote reservoir, that sounds steep

[MyFragileHalogen]

Originally Posted by fanatic1

$9k? Even with remote reservoir, that sounds steep

In PNW it's way more expensive with BMWs than socal in general. And this shop is not cheap but do provide great track support and setup/testing and all that.

If 2Way with no remote has same performance I would go for that and save a couple grand, but it sounds like the remote has benefits. Definitely I'd appreciate insights on that.

[fanatic1]

Originally Posted by MyFragileHalogen

In PNW it's way more expensive with BMWs than socal in general. And this shop is not cheap but do provide great track support and setup/testing and all that.

If 2Way with no remote has same performance I would go for that and save a couple grand, but it sounds like the remote has benefits. Definitely I'd appreciate insights on that.

Have zero experience here, other than a quote - all in at $4000 1wnr, but I do have camber plates + $700 install. Add maybe $1500 for remote and your Quote seems a lot more reasonable.

[MyFragileHalogen]

Originally Posted by fanatic1

Have zero experience here, other than a quote - all in at $4000 1wnr, but I do have camber plates + $700 install. Add maybe $1500 for remote and your Quote seems a lot more reasonable.

Looks like there are lots of extra parts besides the damper kit itself that drives up the cost even before labor.

I used to live in socal and had my F30 springs and shocks installed for $250 at EAS in 2013. Moved up here two years after and shops here called like $750 for putting stock shocks and springs back in. Well it would be a good thing for people working in the industry if that money goes to the workers without all ending up in shop owner's pocket though. Well here at least we don't pay sales tax.