[zanchee]

I track my M2C fairly regularly, and I’ve been looking to move to 18” wheels if possible.

I have the 2NH brakes, which surely don’t clear 18” wheels.

I’ve been thinking about getting the brakes off of an M3/M4 (Blue brakes)

Main reasons over the AP racing fronts…
- Upfront Cost
- Non OE rotor/pads means I can’t order from FCP with lifetime replacement.

Has anyone else done this? What are your experiences? Are there alternatives that would allow me to continue running OE parts?

[zanchee]

I was looking at brembo’s F AL D42 brakes which look identical to the blue brakes…

[Ab28]

Buy the adapter brackets from Track/S

You can continue to use the 2NH factory caliper, but need to change the rotors. (unless you shave down the caliper to use the stock 400mm disc)

A lot of guys are very happy with this as an option to run 18s.

[zanchee]

Downside is… I don’t get free rotors though.

[ThreeStripes]

My .02c

Don’t do it. The allure of cheap running costs is a trap unless you’re running stock power on a track that’s easier on the brakes. If that’s you, go for it.

My blues are holding up just fine running ~450whp-475whp on a track that doesn’t use 5th gear but outside of this narrow use case, on tracks with longer straights, they’re likely out of their ideal operating range. I only see 124mph peak on the catalyst. I’ll make the move over to AP fronts once these start leaking or otherwise demand a rebuild which will come eventually.

APs have a high cost of entry and a high operating cost but braking confidence is one of the single most important things on track. Fresh heat cycled rubber ain’t cheap either.

[zanchee]

Yea that makes sense. I guess I'll try and stick with 19" for now.

[ThreeStripes]

APs pop up on here at a discount occasionally. A set of 9668s just traded for ~4k. The 9660 can be had for ~3k on the used market. Then it’s on to hemorrhaging money for Paragon or AP replacement rings.

[E90convert]

If you're satisfied with the braking performance of 2NH and tire selection at 19", I don't think you will get a running cost payback for changing calipers. Especially if you are taking advantage of the FCP lifetime warranty on pads and rotors. The 2NH rotors/pads are a significant investment from FCP, but at least you only have to do it once.

[M1500Z]

Some thoughts I have...

APs
Pros

• Numerous pad compound choices
• 9668 calipers will give you more usable pad thickness
• Pad changes are quick, even quicker with the 9668 quick-release clip
• No dust boots to melt, high-temp seals that will last
• Significant unsprung weight savings
• No pad knock-back
• Easily run 18" wheel/tire combos

Cons

• Racing brakes mean noise and dust—anti-knock-back springs cause pad drag (noise and dust), and pads rattle around (depends on manufacturer)
• No dust boots may be an issue for your usage
• Not a low-cost option

2NH
Pros

• Big beefy caliper provides good brake feel
• Competition owners already have them
• FCP or similar offers cheaper running costs

Cons

• Heavy caliper and giant rotor
• Must run 19" wheel/tire combo
• Pad compound choices are lacking
• Pad changes require caliper being removed
• Pad knock-back (I experienced this with pads worn ~40%)
• OE calipers mean boots to melt, seals may be damaged due to track use

Custom 2NH for 18"
Pros

• Big beefy caliper provides good brake feel
• Competition owners already have them
• Can run 18" wheel/tire combo
• Lighter weight rotor than OE
• OE caliper is better for street use

Cons

• Heavy caliper
• Pad compound choices are lacking
• Pad changes require caliper being removed
• Pad knock-back (I experienced this with pads worn ~40%)
• OE calipers mean boots to melt, seals may be damaged due to track use

Blue brakes
Pros

• Caliper is capable of track use
• Lighter option than 2NH
• Easy pad swaps that don't require caliper removal
• FCP or similar offers cheaper running costs
• Can run 18s
• OE caliper is better for street use

Cons

• Pad knock-back (I did not run these long enough to experience this)
• OE calipers mean boots to melt, seals may be damaged due to track use

Unknown to me

• Can they hold up to lapping at a high pace and maintain consistency?

Each option has pros and cons. Purely from a braking performance standpoint, there's going to be a ceiling for each system—the APs (or Alcon, or similar race-engineered system) will be significantly higher, but that doesn't mean it's the best option for you. zanchee, if I was you, I'd ask myself these questions:

• How much do I prioritize track performance vs. cost?
• Why am I thinking about running 18" wheels/tires?
• What compromises am I willing to make?
• How brake-heavy are the tracks I frequent?
• What is my pace today, and what are my track goals?

When I was in your situation, I went with the APs because there wasn't yet a buy-it-now option to make the 2NH work within an 18" wheel. This turned out to be the right decision long-term as I tracked the car quite heavily at brake-heavy tracks. If I had gone with the custom 2NH setup, it likely would've just delayed the inevitable.

[zanchee]

M1500Z really great write up! Appreciate you taking the time! Definitely helps as I work through it. I’ve decided to stick with the 19” and OE for now, is I believe there’s still quite a margin growth for me first.

[ThreeStripes]

Originally Posted by zanchee

M1500Z really great write up!

+1

[NSXR]

Originally Posted by M1500Z

Some thoughts I have...

APs
Pros

• Numerous pad compound choices
• 9668 calipers will give you more usable pad thickness
• Pad changes are quick, even quicker with the 9668 quick-release clip
• No dust boots to melt, high-temp seals that will last
• Significant unsprung weight savings
• No pad knock-back
• Easily run 18" wheel/tire combos

Cons

• Racing brakes mean noise and dust—anti-knock-back springs cause pad drag (noise and dust), and pads rattle around (depends on manufacturer)
• No dust boots may be an issue for your usage
• Not a low-cost option

2NH
Pros

• Big beefy caliper provides good brake feel
• Competition owners already have them
• FCP or similar offers cheaper running costs

Cons

• Heavy caliper and giant rotor
• Must run 19" wheel/tire combo
• Pad compound choices are lacking
• Pad changes require caliper being removed
• Pad knock-back (I experienced this with pads worn ~40%)
• OE calipers mean boots to melt, seals may be damaged due to track use

Custom 2NH for 18"
Pros

• Big beefy caliper provides good brake feel
• Competition owners already have them
• Can run 18" wheel/tire combo
• Lighter weight rotor than OE
• OE caliper is better for street use

Cons

• Heavy caliper
• Pad compound choices are lacking
• Pad changes require caliper being removed
• Pad knock-back (I experienced this with pads worn ~40%)
• OE calipers mean boots to melt, seals may be damaged due to track use

Blue brakes
Pros

• Caliper is capable of track use
• Lighter option than 2NH
• Easy pad swaps that don't require caliper removal
• Can run 18s
• OE caliper is better for street use

Cons

• Pad knock-back (I experienced this with pads worn ~40%)
• OE calipers mean boots to melt, seals may be damaged due to track use

Unknown to me

• Can they hold up to lapping at a high pace and maintain consistency?

Each option has pros and cons. Purely from a braking performance standpoint, there's going to be a ceiling for each system—the APs (or Alcon, or similar race-engineered system) will be significantly higher, but that doesn't mean it's the best option for you. zanchee, if I was you, I'd ask myself these questions:

• How much do I prioritize track performance vs. cost?
• Why am I thinking about running 18" wheels/tires?
• What compromises am I willing to make?
• How brake-heavy are the tracks I frequent?
• What is my pace today, and what are my track goals?

When I was in your situation, I went with the APs because there wasn't yet a buy-it-now option to make the 2NH work within an 18" wheel. This turned out to be the right decision long-term as I tracked the car quite heavily at brake-heavy tracks. If I had gone with the custom 2NH setup, it likely would've just delayed the inevitable.

This post needs to be a sticky somewhere.

[FaRKle!]

There's also the cheaper Paragon BBK using the older AP caliper if you don't want to spend AP Radical money.

Only the front caliper needs to be changed anyways.

If you go with F8x blue Brembos you need to change both the front and rear or you'll probably end up with some really funky brake bias. AP or Paragon front only, you can keep the stock rear.

[Mahduece]

Originally Posted by FaRKle!

There's also the cheaper Paragon BBK using the older AP caliper if you don't want to spend AP Radical money

That is a $$ savings that is hard to ignore compared to AP. What’s the trade off?

[egparson202]

Originally Posted by M1500Z

Some thoughts I have...

APs
Pros

• Numerous pad compound choices
• 9668 calipers will give you more usable pad thickness
• Pad changes are quick, even quicker with the 9668 quick-release clip
• No dust boots to melt, high-temp seals that will last
• Significant unsprung weight savings
• No pad knock-back
• Easily run 18" wheel/tire combos

Cons

• Racing brakes mean noise and dust—anti-knock-back springs cause pad drag (noise and dust), and pads rattle around (depends on manufacturer)
• No dust boots may be an issue for your usage
• Not a low-cost option

2NH
Pros

• Big beefy caliper provides good brake feel
• Competition owners already have them
• FCP or similar offers cheaper running costs

Cons

• Heavy caliper and giant rotor
• Must run 19" wheel/tire combo
• Pad compound choices are lacking
• Pad changes require caliper being removed
• Pad knock-back (I experienced this with pads worn ~40%)
• OE calipers mean boots to melt, seals may be damaged due to track use

Custom 2NH for 18"
Pros

• Big beefy caliper provides good brake feel
• Competition owners already have them
• Can run 18" wheel/tire combo
• Lighter weight rotor than OE
• OE caliper is better for street use

Cons

• Heavy caliper
• Pad compound choices are lacking
• Pad changes require caliper being removed
• Pad knock-back (I experienced this with pads worn ~40%)
• OE calipers mean boots to melt, seals may be damaged due to track use

Blue brakes
Pros

• Caliper is capable of track use
• Lighter option than 2NH
• Easy pad swaps that don't require caliper removal
• Can run 18s
• OE caliper is better for street use

Cons

• Pad knock-back (I experienced this with pads worn ~40%)
• OE calipers mean boots to melt, seals may be damaged due to track use

Unknown to me

• Can they hold up to lapping at a high pace and maintain consistency?

Each option has pros and cons. Purely from a braking performance standpoint, there's going to be a ceiling for each system—the APs (or Alcon, or similar race-engineered system) will be significantly higher, but that doesn't mean it's the best option for you. zanchee, if I was you, I'd ask myself these questions:

• How much do I prioritize track performance vs. cost?
• Why am I thinking about running 18" wheels/tires?
• What compromises am I willing to make?
• How brake-heavy are the tracks I frequent?
• What is my pace today, and what are my track goals?

When I was in your situation, I went with the APs because there wasn't yet a buy-it-now option to make the 2NH work within an 18" wheel. This turned out to be the right decision long-term as I tracked the car quite heavily at brake-heavy tracks. If I had gone with the custom 2NH setup, it likely would've just delayed the inevitable.

Thanks for summarizing all this. Very helpful.

When it’s time for fresh rotors, I’ll be making a decision. At present I’m leaning toward Custom 2NH for 18" but the possibility (likelihood?) of destroying the dust boots & seals gives me some pause. I ran into an upgrade kit for the 2NH calipers that adds high temp seals and stainless pistons, but I think it may have been $600. I think you can also get anti knock-back springs. But at that point the AP’s are not a tremendous amount more.

Does anyone here have any experience with the upgraded 2NH seals & pistons? Adding anti knock-back springs?

[M1500Z]

Originally Posted by egparson202

Thanks for summarizing all this. Very helpful.

When it’s time for fresh rotors, I’ll be making a decision. At present I’m leaning toward Custom 2NH for 18" but the possibility (likelihood?) of destroying the dust boots & seals gives me some pause. I ran into an upgrade kit for the 2NH calipers that adds high temp seals and stainless pistons, but I think it may have been $600. I think you can also get anti knock-back springs. But at that point the AP’s are not a tremendous amount more.

Does anyone here have any experience with the upgraded 2NH seals & pistons? Adding anti knock-back springs?

Glad it's helpful. SCMTX went through this a while back. Here's the thread that discusses that AKB springs for 2NH calipers—I'm not sure if high-temp seals/boots were also done. I came across someone melting the high-temp boots, but it may be possible to prevent that through good ducting or ti-shims or a combination of the two.

Years ago when I worked for a shop, we ran some cars on OE Brembos. Dust boots would commonly melt, and would get gummed up around the piston bore along with any track grit they picked up. The seals seemed to be OK, so for us, it was more about the risk of the melty-crusty dust boots damaging the seal or piston. Once the cars got faster, we moved to Stoptechs.

[egparson202]

Originally Posted by M1500Z

Glad it's helpful. SCMTX went through this a while back. Here's the thread that discusses that AKB springs for 2NH calipers—I'm not sure if high-temp seals/boots were also done. I came across someone melting the high-temp boots, but it may be possible to prevent that through good ducting or ti-shims or a combination of the two.

Years ago when I worked for a shop, we ran some cars on OE Brembos. Dust boots would commonly melt, and would get gummed up around the piston bore along with any track grit they picked up. The seals seemed to be OK, so for us, it was more about the risk of the melty-crusty dust boots damaging the seal or piston. Once the cars got faster, we moved to Stoptechs.

Thanks. I’ll read that thread.

I’m planning to use these deflectors. https://www.bimmerworld.com/BimmerWo...F8X-M3-M4.html Maybe adding Ti shims will be enough?

If I remember correctly, the AP’s don’t have dust boots. Do you know? And if not, what would be the down side to removing them from the 2NH calipers?

[ThreeStripes]

Knock on wood, my blues have held up to a ton of abuse year after year. 124mph vmax but so far so good. Besides the boots disintegrating, seals and pistons are hanging tough so the stock kit seems to be able to have some life.

I’ll move to APs when the time comes.

[SCMTX]

Originally Posted by M1500Z

Glad it's helpful. SCMTX went through this a while back. Here's the thread that discusses that AKB springs for 2NH calipers—I'm not sure if high-temp seals/boots were also done. I came across someone melting the high-temp boots, but it may be possible to prevent that through good ducting or ti-shims or a combination of the two.

Years ago when I worked for a shop, we ran some cars on OE Brembos. Dust boots would commonly melt, and would get gummed up around the piston bore along with any track grit they picked up. The seals seemed to be OK, so for us, it was more about the risk of the melty-crusty dust boots damaging the seal or piston. Once the cars got faster, we moved to Stoptechs.

I never touched the seals or anything else in the calipers. I don’t remember how many days I had on them when I sold the car, but never had any issues after anti-kickback springs, good pads, endless rf 650, brake lines with the heat reflecting sleeve. I have a Alcon (the cheapest ones, 6 piston 400mm/4 380) on my F80 and it took me quite awhile to get these calipers, pads, rotors to be close to as consistent as the 2NH kit.
In hindsight, if someone is going to spend a consider amount of time on track, I’d recommend buying one of the good $5-$6K kits for the front axle. Buy once cry once.

[egparson202]

Originally Posted by SCMTX

I never touched the seals or anything else in the calipers. I don’t remember how many days I had on them when I sold the car, but never had any issues after anti-kickback springs, good pads, endless rf 650, brake lines with the heat reflecting sleeve. I have a Alcon (the cheapest ones, 6 piston 400mm/4 380) on my F80 and it took me quite awhile to get these calipers, pads, rotors to be close to as consistent as the 2NH kit.
In hindsight, if someone is going to spend a consider amount of time on track, I’d recommend buying one of the good $5-$6K kits for the front axle. Buy once cry once.

I’ve heard that one before. It’s something I usually say when I just drained my racing account again.

I had the AP’s on another car and they were great for sure. I dunno. I’m still tempted by downsized 2NH brakes. We’ll see.

[SCMTX]

Originally Posted by egparson202

I’ve heard that one before. It’s something ai usually say when I just drained my racing account again.

I had the AP’s on another car and they were great for sure. I dunno. I’m still tempted by downsized 2NH brakes. We’ll see.

Don’t get me wrong, I really enjoyed by 2NH brakes with anti-kickback springs. With the Girodisks they were great. The stock rotors didn’t make it very long with track duty.

[egparson202]

Originally Posted by SCMTX

Don’t get me wrong, I really enjoyed by 2NH brakes with anti-kickback springs. With the Girodisks they were great. The stock rotors didn’t make it very long with track duty.

Yeah, I can already see it coming. For the price of fresh rotors you’re at a crossroads. It’s an invitation to downsize with AP’s (a lightweight luxury I could justify) or 2NH, Track/S brackets, AKB srpings and Girodisk rotors (a budget upgrade). Both are just a ticket to 18” wheels and tires and all the benefits they bring. You can see I’m talking myself into it, right?

BTW the links I’ve seen for the AKB springs are broken. Where’d you get them?