[SCMTX]

Originally Posted by egparson202

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?

I believe I got the springs from
https://www.zeckhausen.com/catalog/index.php

I also picked up my Alcon AKB springs from Alconkits.com. They also sell a piston removal tool….granted I just used vice grips and rags…which I do NOT recommend.

Not to complicate your life any further…there are many choices and these guys provide really great support.
https://alconkits.com/collections/bmw

I REALLY wish I knew someone made a bracket to run 18s with the 2NH calipers!

I always try the cheaper route. I usually regret it. Eventually I end up with a workable option. However, hitting the brakes at 140+ and knowing your pedal, friction will be the same every time, and you are as light as you’re ever going to get is probably pretty priceless.

[CSBM5]

Originally Posted by egparson202

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?

I've never had a dust boot or seal problem when using Ti shims (note: on my E39 M5, E90 M3, and a Stoptech BBK system). They are fantastic at reducing not just conduction heat transfer from the backing plate to piston interface but also especially radiation heat transfer from a hot backing plate to the piston/dust cover/caliper (i.e. anything that can "see" the backing plate from a radiation point of view -- it's called the radiation view factor). This mode of heat transfer increases rapidly with pad wear/increased backing plate temperatures (radiation heat transfer is proportional to the delta-T to the 4th power).

In summary Ti shims help in three ways: (1) two thermal contact resistances added in the conduction heat path from backing plate to caliper piston(s); (2) thermal conduction resistance added in heat path from backing plate to piston (function of shim thickness and shim thermal conductivity) -- this is likely a small portion of their usefulness due to the very thin shim; (3) completely changes the radiation component by introducing a much cooler Ti shim as essentially the complete view factor for the piston and dust boots. The Ti shim runs much cooler than the backing plate.

Additionally, never run pads down to very thin material thickness. Recall that the pad material is a very good heat insulator, and the thinner it is, the higher the backing plate temperatures go.

With knockback springs and Ti shims plus good pads, I would think the 2NH setup would work great.

[medphysdave]

Updrading to the Ti 2NH pistons should also be a win.

[NSXR]

Originally Posted by medphysdave

Updrading to the Ti 2NH pistons should also be a win.

I think the Ti 2NH piston is a myth. IIRC, Track/S debunked it.

[medphysdave]

Originally Posted by NSXR

I think the Ti 2NH piston is a myth. IIRC, Track/S debunked it.

As a factory component yes. BUT then he made some sets for the 2NH. I've got a set waiting for install.

[Track/S]

Originally Posted by NSXR

I think the Ti 2NH piston is a myth. IIRC, Track/S debunked it.

As David mentioned, I have made 3 sets (the 3 most expensive sets in the world, lol).

[medphysdave]

Originally Posted by Track/S

As David mentioned, I have made 3 sets (the 3 most expensive sets in the world, lol).

Ha, they are super fun to hand to people and see the perplexed look.
3 sets? The price of 2nh pistons made from unobtanium just went up.

[NSXR]

Originally Posted by medphysdave

As a factory component yes. BUT then he made some sets for the 2NH. I've got a set waiting for install.

Oh, I missed that! Sorry!

For the man who has everything; Ti 2NH pistons.

[medphysdave]

I may need a custom magnesium shift knob