Alcon BBK via Bimmerworld or AP Racing Pro 5000R?

[DRLane]

Originally Posted by VictorH

For most parts yes, but a properly engineered braking system generally needs pad, rotor and fluid replacement as indicated. No moving and flipping brake pads. SYT-Shadow and I as well as others have run the PFC Z-54 brake kit for literally years with no abnormal pad wear whatsoever regardless of suspension, pad type or use. It's an engineering/design problem which track drivers like us should not have to tolerate.

This makes tons of sense, and I agree with y'all. SYT has articulated his frustrations with the problem to the nth degree.

I don't however subscribe to the "these cars and parts should just work without any oversight" logic. When you consider the activity's risks.

[slcook54]

Given the popularity of the AP kit and other folks running PFC or Alcon, what is the theory on the tapering? Are the piston sizes not property sizes or as SYT_Shadow alluded, is the lightness contributing to the caliper actually bending (assuming that's what he meant).

[omgzirra_exe]

Originally Posted by slcook54

Given the popularity of the AP kit and other folks running PFC or Alcon, what is the theory on the tapering? Are the piston sizes not property sizes or as SYT_Shadow alluded, is the lightness contributing to the caliper actually bending (assuming that's what he meant).

ill probably check my brake pads on the weekend. i did a good rip up my local mt road.

but I must say I am LOVING the alcons right now. the Xp12 was a good choice for street/canyon driving. the XP20's I have for track day will be tested soon.

I'll get into more details as I drive the car.

so far trail braking and giving a bit more mid apex has been a nice confident feeling.

[slcook54]

Essex also states this on their site.

https://www.essexparts.com/news-blog...d-owners-guide

[DrFerry]

After reading many of the posts on this thread, and having once driven professionally for over five years (a while back), I thought I'd throw my hat into the ring here. In my experience, unusually high degrees of brake pad taper and premature wear are caused by multiple things, and all of them typically need some degree of mitigation, adjustment, or modifications:

1) COOL air goes a long, long way to helping all aspects of braking performance and keeping components cooler on track. Brake ducting (which is properly oriented towards the rotor center core) is paramount since the rotor is a vaned air pump moving air radially from center to extremity. Incorrect rotor direction of rotation exacerbates rotor heat build up, because rotors are typically directional i.e. left and rights. The E9X chassis is tight for adding ducting, but solutions exist. Start here:
.
https://www.turnermotorsport.com/p-3...it-bmw-e9x-m3/
.
https://indstyledotcom.wordpress.com...e-motorsports/
.

.
2) Unless the track pads being used are of of high quality there's a chance the pad friction material itself may not be a) homogenous or b) bonded uniformly to the substrate backing plate. This is a function of manufacturing quality control and chemical mixing. I can personally recommend the following pad manufacturers: PAGID, Performance Friction, Mintex, and Ferodo.

3) Caliper design is sometimes biased towards lightweight rather than rigidity in order to reduce unsprung weight. However, lightweight calipers not only are typically less rigid but also have lower (less) thermal heat capacity. In other words they get hot quickly even in rear axle positions. Example: A cast iron skillet takes longer to warm up than a thinner and lighter aluminium frying pan. So the caliper materials, its weight, and the design of the caliper can all enhance or detract from its rigidity thereby leading to "caliper flex" - or not as in the case of say PFC.

4) Wheel bearing float (play) and or soft bushing compliance can cause the suspension geometry to move under dynamic loads. If the hub isn't fixed to suspension arms and links rigidly, the forces seen by the hub (as generated by the caliper and pads) tend to vary and can be affected by escalating temperatures. Heim joints or rose joints as well as solid bushings seek to address suspension compliance but it has been my experience that rigidly mounted calipers and hubs see lower rates of pad taper. I'm not exactly sure of all the mechanisms in play, but if you can afford to reduce hub float and suspension compliance for on track work then I recommend doing it.

5) Caliper piston size and placement play a role in the brake pressure distribution force field 'seen' by the brake pad backing plate. IF the piston sizes are not uniform in a multi piston caliper design, then for any given master cylinder displacement the volume of brake fluid displaced by each piston may not be equal and uniform to all the other larger or smaller caliper pistons. Pressure = Force X Area. So if the area of each piston is not the same then the brake pressure locally seen by the backing plate won't be equal .. will it? Ideally the caliper pistons should be the same size for a uniform pressure distribution field..

I think I'm going to leave it there, but suffice to say the issue is complex and multi-variable. The 1) above is huge so address that one first of all.
.
All hail the King.. Even if the PFC BBK for E9X M3 is dead.. Check out the robustness of its design.
.

[slcook54]

Doctor Ferry in the house. Mic drop.

[tsk94]

Thiccc bois:

[DrFerry]

Originally Posted by tsk94

Thiccc bois: (pads)

Sorry to ask, but what sort (type) of ALCONs are these? They look fairly decent. Thanks for posting the photos.

[tsk94]

SYT_Shadow might be able to answer this better then I. My understanding is it's one of Alcon's race calipers that was adapted in conjunction with Bimmerworld to make a new BBK for E9X/F8X in replacement for the PFC kits that are no longer available.

Visually, they are much more impressive and lighter then the PFC's, hoping the performance will also meet expectations.

[DRLane]

Originally Posted by tsk94

SYT_Shadow might be able to answer this better then I. My understanding is it's one of Alcon's race calipers that was adapted in conjunction with Bimmerworld to make a new BBK for E9X/F8X in replacement for the PFC kits that are no longer available.

Visually, they are much more impressive and lighter then the PFC's, hoping the performance will also meet expectations.

What's the new project car? Calipers look awesome.

[omgzirra_exe]

checking in also!



18x10.5 TE37SL

[slcook54]

Surprised the Alcon guys still have their lettering. :-)

[SYT_Shadow]

Originally Posted by DrFerry

Sorry to ask, but what sort (type) of ALCONs are these? They look fairly decent. Thanks for posting the photos.

Originally Posted by tsk94

SYT_Shadow might be able to answer this better then I. My understanding is it's one of Alcon's race calipers that was adapted in conjunction with Bimmerworld to make a new BBK for E9X/F8X in replacement for the PFC kits that are no longer available.

Visually, they are much more impressive and lighter then the PFC's, hoping the performance will also meet expectations.

This is not the toy alcon kits that are also in the market for the F8X. BMW went to Alcon for their M2 CSR racecar and the kits in this thread are the aftermarket versions for the E9X and F8X.

It's like what PFC would have built if they had stayed on the market. We've spent two years with one car with PFC and the other with Alcon and the Alcons are at the level, with some advantages like the insane 36mm rotors that last even longer than the PFC rotors.
There are still things we prefer about the PFC kit, but between the calipers being NLA and our move to F8X cars, now GTS1 & GTS2 have Alcons. Nickel plated
If the PFC kit were still in production, we might have instead spent a few months getting brackets to adapt the PFC rears to the F8X chassis -like we did with the front PFC-, but we have one full PFC kit and one front-only PFC, and as both cars must be identical for ease of swaps/spares etc, both are moving to Alcons.

The front-only PFC kit is sold and the full PFC will be for sale sometime this year.

[tsk94]

Originally Posted by DRLane

What's the new project car? Calipers look awesome.

My dad and I picked up an F82 M4
SYT_Shadow steered us that route after selling our E92 to Jason and discussing replacements, so far it's been a pleasant tranistion. Can't wait to try it out w/ the Alcons and new KW's next week.
Just going to be a nice clean track build this time - half cage, rear seat delete (both done already), race seats and bolt-ons.
Also got an E36 project we're working on slowly as well, but that's more of a novelty project for us as we both just have a soft spot for them.

This morning once the suspension + brakes were all installed and initial alignment and ride height set:

[slcook54]

Originally Posted by tsk94

My dad and I picked up an F82 M4
SYT_Shadow steered us that route after selling our E92 to Jason and discussing replacements, so far it's been a pleasant tranistion. Can't wait to try it out w/ the Alcons and new KW's next week.
Just going to be a nice clean track build this time - half cage, rear seat delete (both done already), race seats and bolt-ons.
Also got an E36 project we're working on slowly as well, but that's more of a novelty project for us as we both just have a soft spot for them.

This morning once the suspension + brakes were all installed and initial alignment and ride height set:

How did you find the f82 stock? I picked up an f80 CS and it feels floaty to me, not planted at all. Somewhat disconcerting with the additional power.

Previous owner did Dinan springs and front monoballs. I added Cup2's.

I ordered the roadsport Ohlins kit from 3DM. Hoping that alleviates it.

[DRLane]

Originally Posted by tsk94

My dad and I picked up an F82 M4
SYT_Shadow steered us that route after selling our E92 to Jason and discussing replacements, so far it's been a pleasant tranistion. Can't wait to try it out w/ the Alcons and new KW's next week.
Just going to be a nice clean track build this time - half cage, rear seat delete (both done already), race seats and bolt-ons.
Also got an E36 project we're working on slowly as well, but that's more of a novelty project for us as we both just have a soft spot for them.

This morning once the suspension + brakes were all installed and initial alignment and ride height set:
[IMG]

View post on imgur.com

[/IMG]

Seems like the most capable BMW platform to build an aggressively capable time attack car. Kudos!

[tsk94]

Originally Posted by slcook54

How did you find the f82 stock? I picked up an f80 CS and it feels floaty to me, not planted at all. Somewhat disconcerting with the additional power.

Previous owner did Dinan springs and front monoballs. I added Cup2's.

I ordered the roadsport Ohlins kit from 3DM. Hoping that alleviates it.

I found it quite good, actually. That said.. we did do front monoballs, camber plates and rear toe arms (and race pads of course) before we actually tracked it. Also ran 295/315 r-comps from the get go. Otherwise, it was stock non-EDC suspension, so it was definitely soft.

The platform is hugely capable though. As much as I prefer the E9X's for the looks, engine and size, the F8X is a hugeeee step onwards on track. Which was our goal, a faster more capable platform. I still think the E9X's are more 'fun' and more raw, but the F82 is really impressive. I feel there is still enough cross over/similarities between the platforms though that my impressions on the brakes would still be relevant to someone who wants to run them on an E9X (suspension probably too for that matter).

I'm expecting it to be almost a new car with the Alcons on + the new 3-way KW competitions.

[MaX PL]

Originally Posted by slcook54

Surprised the Alcon guys still have their lettering. :-)

Here's mine. That happened after only about two days.

[SYT_Shadow]

Originally Posted by MaX PL

Here's mine. That happened after only about two days.

In the pic it looks like it's painted black now lol

[SYT_Shadow]

Originally Posted by omgzirra_exe

checking in also!



18x10.5 TE37SL

Careful, those rotors are installed backwards. They have to be swapped side to side. Same thing as the rears if the rears look the same
The grooves on the rotors have to be reversed vs oem.

[MaX PL]

wow yeah good catch Shadow.

[omgzirra_exe]

Originally Posted by SYT_Shadow

Careful, those rotors are installed backwards. They have to be swapped side to side. Same thing as the rears if the rears look the same
The grooves on the rotors have to be reversed vs oem.

oh okay, thanks!

i honestly was talking with my mechanic and we were both not sure either lol it didn't come marked L/R I will fix it~ good thing its easy to flip lol.