Track forum general chit chat

[M3SQRD]

Originally Posted by mikerunt

I’ll have to try 34 on R7s - for whatever reason (past bad shop advice?) I was always told to target ~30-32

I target 33-34 psi (or average) on R7s. 32 psi is too low with poor support and 35 is too high and grip drops off. I guess 33.5 psi is what works best for me.

[phefner]

Just finished a few track days, Road America and AutoBahn Club. Swapped pads and changed fluids so all ready for regular street duties.

My front pads, PFC 08, have these holes in the backing plate. Its a solid plate when new, but very symmetrical. Almost with a purpose, or common flaw I guess.

Anyone help with why these are there?

[ZAPDDY]

Originally Posted by D_SheerDrivingPleasure

I''m an excellent driver. (Movie ref, anyone?)

32 is too low for a big heavy car like a Camero or F8x IMO

With the goal of not over analyzing, i don't monitor my tire temps I'm just shooting for even wear across the tire contact patch.

Quote from Rain Man

I talked to you at WGI, (Jeff yellow F80) you had great things to say about the Hoosier TAP. Well I’m going to find out this weekend at VIR. At what hot pressures did they perform best?

[M3SQRD]

Originally Posted by phefner

Just finished a few track days, Road America and AutoBahn Club. Swapped pads and changed fluids so all ready for regular street duties.

My front pads, PFC 08, have these holes in the backing plate. Its a solid plate when new, but very symmetrical. Almost with a purpose, or common flaw I guess.

Anyone help with why these are there?

Are you still using stock aluminum pistons or have you upgraded to Racing Brake’s stainless steel pistons? How much 08 pad compound is left? How many miles or months were these pads installed in the calipers? The marks around the holes are from the contact rings of the caliper pistons.

It looks the inner diameter of the pistons were acting like a punch, creating the two holes per pad backing plate and you can see the circular discs sitting in the holes. I have never seen a backing plate with holes created by the pistons. I’ve seen small circular indentations from the piston ID and OD but never through holes. This is a new one that’s going to require some creative thinking to figure out what happened

[phefner]

M3SQRD Great questions...I feel like such a nob, even after 5 years of doing this. It felt like we were losing that initial bite as the session wore on. Felt like I was using more pedal pressure than usual. Didn't feel like fade from boiled fluid. I've had that before, very distinct. So I wrapped it up early to be safe.

Yes stock pistons. The lines to the calipers are steel, but everything else is stock. Surprisingly, the boots are still intact.

The pad is about 50% used. They were installed just before I did Road America in them, so 3 weeks ago and about 750 street miles.

When coming off the track the "pinging" is loud. The caliper color is now a very dark and ugly green.

Plan is to take off and rebuild with more track focused components. I'm definitely going to add the BimmerWorld Brake Cooling Deflector. Leaning towards an upgrade to a bigger brake kit. Like 6 piston front and 4 rear from AP Racing.

I sent photos to PFC, will post what they say. Thanks again for weighing in.

UPDATE:
Got a hold of my SA at BimmerWorld and the pads do come from the Mfg with those holes. The pictures on the webpage shows a thin silver color backing plate that overlays the back side of the pad. That didn't come with the pads. So that mystery has been solved. Guess I'm an idiot for putting those on without an additional backing plate.

There certainly is an impression being made on the back side of the pad. All this just circles back to I need updated brake infrastructure.

I'm not a driver who slams on the brakes at the last possible second to make the turn. I do a lift and gradual, but with purpose, application of brake when tracking. This wasn't an issue the first couple of years with the M3. I have a ton to learn yet, there is a lot more time on the table and I have more performance to squeeze more out of the car. Upgrades to the brakes seems to be a priority now. Project over the winter: cooling deflectors & Big Brake Kit. Or buy that Porsche GT4CS I'm stalking. Surrender to whatever this affliction is with the track.

[D_SheerDrivingPleasure]

Originally Posted by ZAPDDY

Quote from Rain Man

I talked to you at WGI, (Jeff yellow F80) you had great things to say about the Hoosier TAP. Well I’m going to find out this weekend at VIR. At what hot pressures did they perform best?

Hi Jeff. You have a bad ass F80!

Yes, the TAPs were terrific at WGI but were a let down at Lime Rock the following weekend. It has been suggested that the lightweight construction of the Ho-Ho's causes them heat soak very quickly. If true, then maybe they were within optimal operating temps for WGI event (fairly cool and cloudy) whereas my Lime Rock event was 70s and sunny. I really hope my experience is not representative. I want to love them, especially since they are made right here in the good ole US of A.

They seemed best at 34/35.

Let us know how they work for you. Have fun at VIR.

[FrankMstein]

Originally Posted by phefner

M3SQRD Great questions...I feel like such a nob, even after 5 years of doing this. It felt like we were losing that initial bite as the session wore on. Felt like I was using more pedal pressure than usual. Didn't feel like fade from boiled fluid.
>>>If your brakes are not blue you over-heated the calipers and fluid period. What fluid are you using?

I've had that before, very distinct. So I wrapped it up early to be safe.

Yes stock pistons.
>>>I have heard that the stock pistons are not SS. SS will help insulate the fluid but not much. Racing Brake sells the SS pistons.

The lines to the calipers are steel, but everything else is stock. Surprisingly, the boots are still intact.
>>>surprised too.

The pad is about 50% used. They were installed just before I did Road America in them, so 3 weeks ago and about 750 street miles.
>>>RA is hard on brakes but you should have more than 50% 08's unless you had 10-12 full 20 minute sessions.

When coming off the track the "pinging" is loud. The caliper color is now a very dark and ugly green.
>>>Hopefully you had a full lap to cool them off. Nowadays they only give you half a lap, not enough. Drive the remaining lap and don't hit the brakes and drive the paddock. 08 run hotter than 11 and if they are green, then you over-heated them and the fluid. If you run with MDM on and/or overdrive the car it will manipulate the calipers to "save" you and will make even more heat. Run with MDM off, light on. I have a person near me with green rear calipers and the first thing I asked him was do you have PFC 08 in the rear and drive with MDM on, he had this ghostly look at me, "how did you know".

Plan is to take off and rebuild with more track focused components.
>>>Racing Brake carries BLUE silicone boots. You have to choose the option. https://racingbrake.com/bb-43bsp/

I'm definitely going to add the BimmerWorld Brake Cooling Deflector.
>>>Westersund has the best (not cheap) cooling kit. I have his rear setup. https://f80.bimmerpost.com/forums/sh...=brake+cooling

Leaning towards an upgrade to a bigger brake kit. Like 6 piston front and 4 rear from AP Racing.
>>>Unnecessary. Rear are super unnecessary. Spend 6k on driver mods. Request that the instructor helps you with track/late/trail braking. What area are you in, upper mid-west?

I sent photos to PFC, will post what they say. Thanks again for weighing in.

UPDATE:
Got a hold of my SA at BimmerWorld and the pads do come from the Mfg with those holes. The pictures on the webpage shows a thin silver color backing plate that overlays the back side of the pad. That didn't come with the pads. So that mystery has been solved. Guess I'm an idiot for putting those on without an additional backing plate.
>>>The silver part is just a shim to help quiet them down and 08 didn't use to come with those, they may now but I doubt it. You do not need those. 08 is a track compound and realistically people don't care about noise and want thicker pads so more compound is added. BUT what you might want are titanium shims. OP mustang makes them for the 2NH setup and someone here has them for the blue brakes. Again not really necessary though but they are inexpensive.

There certainly is an impression being made on the back side of the pad. All this just circles back to I need updated brake infrastructure.
>>>at one point PFC used a 1mm thinner baking plate (more friction material) and they began to bend and the compound would crack, check for cracks. Unless the pad is bent or dished they are fine. I would not do more than one day (5 sessions at RA) on <50% pad thickness.

I'm not a driver who slams on the brakes at the last possible second to make the turn. I do a lift and gradual, but with purpose, application of brake when tracking.
>>>That last minute technique is how to keep the brakes from over-heating and if you are "street braking", you are doing it wrong.

This wasn't an issue the first couple of years with the M3. I have a ton to learn yet, there is a lot more time on the table and I have more performance to squeeze more out of the car. Upgrades to the brakes seems to be a priority now. Project over the winter: cooling deflectors & Big Brake Kit. Or buy that Porsche GT4CS I'm stalking.
>>>GT4's are god like.

Surrender to whatever this affliction is with the track.

See above>>>

[SYT_Shadow]

Originally Posted by ZAPDDY

Quote from Rain Man

I talked to you at WGI, (Jeff yellow F80) you had great things to say about the Hoosier TAP. Well I’m going to find out this weekend at VIR. At what hot pressures did they perform best?

See you this weekend! Small world!

[phefner]

FrankMstein

Motul RBF660. Used 3 bottles of it.

Many thanks for all the additional comments. I did have the PFC 08 Front and PFC 332 Rear. I think I get what your talking about with the last minute braking. Maybe my application was built as a response to keep the rear end planted under braking.

Located 2 hours from Road America, just north of Chicago.

Update:

Frank, I’ve reread you response like 5 times. Your such an asset. Many thanks for sharing that knowledge. Will take and act on your suggestions.

If your an instructor in the Midwest…let me know what club and track.

[M3SQRD]

Originally Posted by phefner

FrankMstein

Motul RBF660. Used 3 bottles of it.

Many thanks for all the additional comments. I did have the PFC 08 Front and PFC 332 Rear. I think I get what your talking about with the last minute braking. Maybe my application was built as a response to keep the rear end plated under braking.

Located 2 hours from Road America, just north of Chicago.

Update:

Frank, I’ve reread you response like 5 times. Your such an asset. Many thanks for sharing that knowledge. Will take and act on your suggestions.

If your an instructor in the Midwest…let me know what club and track.

When a certain person used to work at PFC, you always get great information about PFC products that aren’t common knowledge. When you next buy pads try either 11, if still available/in-stock, or matching 331 Front/332 Rear. 11/332 might be an interesting combo with one being progressive (11) and one being digressive (332).

[FrankMstein]

Originally Posted by M3SQRD

When a certain person used to work at PFC, you always get great information about PFC products that aren’t common knowledge.

[FrankMstein]

Originally Posted by phefner

FrankMstein

Motul RBF660. Used 3 bottles of it.

Many thanks for all the additional comments. I did have the PFC 08 Front and PFC 332 Rear. I think I get what your talking about with the last minute braking. Maybe my application was built as a response to keep the rear end planted under braking.

Located 2 hours from Road America, just north of Chicago.

Update:

Frank, I’ve reread you response like 5 times. Your such an asset. Many thanks for sharing that knowledge. Will take and act on your suggestions.

If your an instructor in the Midwest…let me know what club and track.

Thanks! Like, subscribe, and hit that notification button! I am in Charlotte and the farthest I'm getting in that direction is Putman Park, my old home track. You get to VIR or Road Atlanta...

[M3SQRD]

Originally Posted by FrankMstein

With each passing year, it feels like PFC has lost some of its dominance over other brands. 05 was my favorite compound and then it was discontinued when the 11 was introduced. 11 is a great compound but I preferred the less progressiveness of the 05. With 11 supposedly being discontinued, 15 would be my next choice but they don’t stock it even in the widely used PFC 7790 pad profile. The 332 has such a low CoF it basically looks like a slightly improved Z-rated (10 compound?) street pad. If the 331 was offered in rear pad profiles, I’d love to try F/R 333/331.

[sly1types]

Originally Posted by M3SQRD

With each passing year, it feels like PFC has lost some of its dominance over other brands. 05 was my favorite compound and then it was discontinued when the 11 was introduced. 11 is a great compound but I preferred the less progressiveness of the 05. With 11 supposedly being discontinued, 15 would be my next choice but they don’t stock it even in the widely used PFC 7790 pad profile. The 332 has such a low CoF it basically looks like a slightly improved Z-rated (10 compound?) street pad. If the 331 was offered in rear pad profiles, I’d love to try F/R 333/331.

Last time i went to order PFC11s for the AP kit they were out of stock. Bimmerworld recommended the 331/332 combo, they do have less bite, but it makes it easier not to over slow the car and thats what they were saying.

They are noisy on the street, VS PFC11 are my all time favorite pad. I was worried about the bias and they said try it, but if you don't like it run 08 rears but i was happy with them.

[phefner]

M3SQRD I’m going to locate and give those 333s a try upfront. Definitely rebuilding the calibers with the kit you suggested. Add the deflection kit, get a little more schooling, see how we do.

Putnam Park just outside of Indy, so isn’t that far away from me. I know a few guys with the Chicago PCA who track there too, so I’ll look into it for next season. Maybe the first stop coming out of winter.

Many thanks for all those ideas with the brakes and pads.

[FrankMstein]

Originally Posted by sly1types

Last time i went to order PFC11s for the AP kit they were out of stock. Bimmerworld recommended the 331/332 combo, they do have less bite, but it makes it easier not to over slow the car and thats what they were saying.

They are noisy on the street, VS PFC11 are my all time favorite pad. I was worried about the bias and they said try it, but if you don't like it run 08 rears but i was happy with them.

There is nothing noisier than 08 in the rear. Good luck with that...!

[dawei213]

Originally Posted by FrankMstein

There is nothing noisier than 08 in the rear. Good luck with that...!

So new/old/different rotors seems to make a difference with the noise of the 08. With my older stock rotors, the 08 squeal like a dump truck, even with the lightest of touch.

When I switch over to the 034 Motorsport rotors, using the same used pads, it'll only squeal on occasion and no where as loud. I'm wondering if it's due to the newest of the rotor or the design.

[FrankMstein]

Originally Posted by dawei213

So new/old/different rotors seems to make a difference with the noise of the 08. With my older stock rotors, the 08 squeal like a dump truck, even with the lightest of touch.

When I switch over to the 034 Motorsport rotors, using the same used pads, it'll only squeal on occasion and no where as loud. I'm wondering if it's due to the newest of the rotor or the design.

Rotor design has 6% influence. The unused rotor will have some dampening factor but there are many other things that affect it more.

[M3SQRD]

Originally Posted by FrankMstein

Rotor design has 6% influence. The unused rotor will have some dampening factor but there are many other things that affect it more.

Minimizing noise from a race compound is more of a black art than a pure scientific process. Pads with a high % of metallic in the compound are going to squeal but it also is what makes the pads perform well over a large temperature range. Vibration isolators do absolutely nothing to minimize noise on race pads. It takes ~25 min to swap pads yet people are too lazy to switch between street-track pads for a track event and then switch back to track-street pads after a track event. These are the same people who then complain about excessive rotor wear and noise on the street when running track pads. They blame the manufacturers, who clearly state their race pads are not to be driven street pads, for the excessive rotor wear rate and then expect the manufacturers to replace for free their destroyed rotors and unevenly worn pads. It’s really bad in the f87 forum where you’ll get attacked for just stating the facts about the use of race pads on the street.

[FrankMstein]

Originally Posted by M3SQRD

Minimizing noise from a race compound is more of a black art than a pure scientific process. Pads with a high % of metallic in the compound are going to squeal but it also is what makes the pads perform well over a large temperature range. Vibration isolators do absolutely nothing to minimize noise on race pads. It takes ~25 min to swap pads yet people are too lazy to switch between street-track pads for a track event and then switch back to track-street pads after a track event. These are the same people who then complain about excessive rotor wear and noise on the street when running track pads. They blame the manufacturers, who clearly state their race pads are not to be driven street pads, for the excessive rotor wear rate and then expect the manufacturers to replace for free their destroyed rotors and unevenly worn pads. It’s really bad in the f87 forum where you’ll get attacked for just stating the facts about the use of race pads on the street.

LOL, yeah! I agree, I've seen. I have seen people get into accidents and blame the pads and find out that the compound is not "street".

It IS a black art and it's been explained to me as such. There are "general" guides to start with using beveled edges, edge shapes, slots, two slots, clips, weights, different ways to adhere the compound to the plate, etc. but calipers play more of a role than you'd think. There is a reason why there are huge weights on the OEM pads. I have even removed the weights from OE and tried to apply to the 08 and 11 in the rear and to no avail. Manufacturers make slight changes to the caliper and you have to start completely over. BTW, PFC is the ONLY manufacturer that does not use copper.