Track forum general chit chat.

[rhyary]

Originally Posted by dparm

255/35R19 fits fine, it's probably what 75% of owners on this board run.

Great. Thank you.
Cap 2 is available at that size.
There are ton of options at 245/35 and 265/35

[admranger]

We used to give out passwords in the classroom sessions that you had to give to the pit out worker. No password, no bueno.

[dparm]

Originally Posted by rhyary

Great. Thank you.
Cap 2 is available at that size.
There are ton of options at 245/35 and 265/35

There are a lot of choices in that size. Cup 2s are very pricey and I think you can do better for less money.

[Chuck's M3]

Originally Posted by admranger

We used to give out passwords in the classroom sessions that you had to give to the pit out worker. No password, no bueno.

Originally Posted by dogbone

In my opinion, it's up to event organizers to quickly become aware of drivers who are out there for the wrong reasons, and they need to take charge of the situation. All the waivers we sign may make it a no-fault environment, but that doesn't mean we should all throw our hands in the air and just say that whatever happens is fine. We look to an event organizer to set the tone for what will be tolerated. Some organizers drop the hammer hard on crappy behavior. Other organizers sit back and let things happen and don't take charge. I was at one event that said their rule was three offs and you were done. And some guy kept flying off. The organizer was uncomfortable being the hammer. He was actually asking the corner worker what he should say.....didn't want to be a bad guy. But you gotta establish yourself as having standards. Otherwise your track event will become the Wild West.

Driver download meetings can be useful, but have you noticed that the worst offending drivers skip the meetings? PCA Las Vegas did something I've never seen before---they put a mark on everyone's wristband after the driver download meeting after the first session. If you skipped the meeting and didn't get the mark, you weren't going back out on track. Nice.

Also, if you see something unsafe out there, report it. So often, I'll hear someone grumble about something that happened on track, but they don't tell the organizer. You gotta tell them. They don't have eyes everywhere. I've always found organizers to be receptive to feedback about what's happening on track.

I was at Laguna Seca with SpeedSF a few days after (on 5/28) and they began issuing these mandatory stickers after the download meeting that followed session 1. This was new to me.


Though it sounded tricky to manage those who ran in multiple run groups.

[kyippee]

Hmm those download session stickers have been used for ages now. At least since some of 2017

[Ximian]

The the local BMW CCA is now starting to use these standardized driver evals so it'll be useful to track this to see how it changes. My first two times at the track, I used the stock brake pads. There were comments about double braking or braking too early in the later sessions as the pads and rotors were starting to overheat, but nothing about smoothness. Once I switched to PFC 08 pads all around, the comments about double braking and inconsistent braking points stopped but braking smoothness on release became an issue. My instructor's goal for me was to improve braking smoothness by releasing the pad slower and later during the turn in, then getting on the throttle. I did manage to improve a bit and had a few corners where the release of the brakes was nearly perfect, but I can't do it without overslowing the car. Has anyone else dealt with a similar thing with stock brakes or is everyone else "cheating" and slowly getting on the throttle while still at 10-20% braking to mask the transition?

[rhyary]

Originally Posted by dparm

There are a lot of choices in that size. Cup 2s are very pricey and I think you can do better for less money.

so for the road, I am just happy with the PS4S 275/30/19. The side wall looks good in proportion to the rear 295/30/19 and I have no complains about the performance. Doing 1:38 at NYST with the PS4S in semi wet condition is very fast.

For the track set, I calculated that the "too narrow" RR 235/35/19 has more rubber on the road (223mm) than a Cap 2 265/35. So for a front track track I want to try something that I calculate to have more rubber that 223mm.

That leaves out the Cap 2 and all its variations.

what's left is the 245/35 Trofeo R (still needs to be measured) and the big one is if I can fir Hoosier 265/35/19 on the front that for sure be more rubber.

The Hoosier is almost twice the cost of the RR and the 245/35 Trofeo R is up there in cost as well. The RR is $230.

So.. next is few track days with the RR and see what lap time I can do. Then probably a set of Trofeo Rs front 245/35 to get a reference (i know they fit) and lastly looking into a way to fit a 265/35 Hoosier. Again for reference.

Once I have the data from all fronts, I will probably will settled on a balance between price and performance.

Rear will stay constant with RR 295/30/19.

AiM will keep me honest with data

Weather and fun is guaranteed.

[M3MPH1S]

Originally Posted by Ximian

The the local BMW CCA is now starting to use these standardized driver evals so it'll be useful to track this to see how it changes. My first two times at the track, I used the stock brake pads. There were comments about double braking or braking too early in the later sessions as the pads and rotors were starting to overheat, but nothing about smoothness. Once I switched to PFC 08 pads all around, the comments about double braking and inconsistent braking points stopped but braking smoothness on release became an issue. My instructor's goal for me was to improve braking smoothness by releasing the pad slower and later during the turn in, then getting on the throttle. I did manage to improve a bit and had a few corners where the release of the brakes was nearly perfect, but I can't do it without overslowing the car. Has anyone else dealt with a similar thing with stock brakes or is everyone else "cheating" and slowly getting on the throttle while still at 10-20% braking to mask the transition?

I just recently retired my stock brakes after 160k miles so I think I can give some decent insight. I've gone through several different pads: Pagid RS19, PFC08, Hawk DTC 60, and Hawk DTC 70. In my opinion the Pagids were the most (relatively) difficult to modulate on release, but it was never a huge issue. Overslowing, on the other hand, certainly was (/is). I'm curious what you mean by getting on the throttle while still at 10-20% braking. Do you mean that you're left foot braking and simultaneously starting to apply throttle or are you saying that you're lifting off the brake at 10-20% and going straight to the throttle? I think in either case (especially the latter) it sounds like you might not be focusing on trail braking. This still won't necessarily help the overslowing issue, but it changes your focus from "I need to come off the brakes smoothly because that's what I'm supposed to be doing" to "I need to come off the brakes smoothly because it's giving me more grip and helping me go faster". What is your current skill level? It may or may not be appropriate for you to start focusing on trail braking just yet.

Edit: I guess if you're mentioning instructors then you're probably still relatively new. I would still encourage you to look up some videos/reading material on trail braking and slowly start to incorporate it into your driving. It's not something you need to do at every corner, but there will be very obvious corners at every track where you can start practicing it and then you can take it from there.

[M3MPH1S]

Originally Posted by dogbone

In my opinion, it's up to event organizers to quickly become aware of drivers who are out there for the wrong reasons, and they need to take charge of the situation. All the waivers we sign may make it a no-fault environment, but that doesn't mean we should all throw our hands in the air and just say that whatever happens is fine. We look to an event organizer to set the tone for what will be tolerated. Some organizers drop the hammer hard on crappy behavior. Other organizers sit back and let things happen and don't take charge. I was at one event that said their rule was three offs and you were done. And some guy kept flying off. The organizer was uncomfortable being the hammer. He was actually asking the corner worker what he should say.....didn't want to be a bad guy. But you gotta establish yourself as having standards. Otherwise your track event will become the Wild West.

Driver download meetings can be useful, but have you noticed that the worst offending drivers skip the meetings? PCA Las Vegas did something I've never seen before---they put a mark on everyone's wristband after the driver download meeting after the first session. If you skipped the meeting and didn't get the mark, you weren't going back out on track. Nice.

Also, if you see something unsafe out there, report it. So often, I'll hear someone grumble about something that happened on track, but they don't tell the organizer. You gotta tell them. They don't have eyes everywhere. I've always found organizers to be receptive to feedback about what's happening on track.

NASA Mid Atlantic has a well organized, disciplined, and respectable group going. They have 4 DE levels (1,2,3,4) - Novice, Intermediate, Intermediate+/Advanced, and Instructor/Advanced+. All groups aside from 4 have several mandatory classroom sessions and you receive a physical card you must turn in to the grid worker to get on track. They are also very adamant about monitoring issues during sessions and discussing it during the classroom. The rule for 2 and 3 (not 100% sure about 4) is that if you make 2 egregious mistakes (e.g. passing under double yellow) and/or 2 four wheel offs then you are demoted 1 group down for the remainder of the event and you need to get a checkride at the next event. They even had a morning sessions where some TTers were warming up with 3, and they took multiple passes under double yellow so their next qualifying session times were DQ'd.

[slicer]

Originally Posted by rhyary

so for the road, I am just happy with the PS4S 275/30/19. The side wall looks good in proportion to the rear 295/30/19 and I have no complains about the performance. Doing 1:38 at NYST with the PS4S in semi wet condition is very fast.

For the track set, I calculated that the "too narrow" RR 235/35/19 has more rubber on the road (223mm) than a Cap 2 265/35. So for a front track track I want to try something that I calculate to have more rubber that 223mm.

That leaves out the Cap 2 and all its variations.

what's left is the 245/35 Trofeo R (still needs to be measured) and the big one is if I can fir Hoosier 265/35/19 on the front that for sure be more rubber.

The Hoosier is almost twice the cost of the RR and the 245/35 Trofeo R is up there in cost as well. The RR is $230.

So.. next is few track days with the RR and see what lap time I can do. Then probably a set of Trofeo Rs front 245/35 to get a reference (i know they fit) and lastly looking into a way to fit a 265/35 Hoosier. Again for reference.

Once I have the data from all fronts, I will probably will settled on a balance between price and performance.

Rear will stay constant with RR 295/30/19.

AiM will keep me honest with data

Weather and fun is guaranteed.

What wheel sizes and offsets are you running?

[rhyary]

Originally Posted by slicer

What wheel sizes and offsets are you running?

Track set 9.5" 28
Road/Rain set 9.5" 22

no spacers either one

[slicer]

Originally Posted by rhyary

Track set 9.5" 28
Road/Rain set 9.5" 22

no spacers either one

Are you running those sizes square? I thought you were using a 295 in the rear. That would be a lot of tire on a 9.5" wheel.

My recollection is that you are limited to 19" by your brakes. Do you have Brembo 380mm kit?

[Ximian]

Originally Posted by M3MPH1S

I just recently retired my stock brakes after 160k miles so I think I can give some decent insight. I've gone through several different pads: Pagid RS19, PFC08, Hawk DTC 60, and Hawk DTC 70. In my opinion the Pagids were the most (relatively) difficult to modulate on release, but it was never a huge issue. Overslowing, on the other hand, certainly was (/is). I'm curious what you mean by getting on the throttle while still at 10-20% braking. Do you mean that you're left foot braking and simultaneously starting to apply throttle or are you saying that you're lifting off the brake at 10-20% and going straight to the throttle? I think in either case (especially the latter) it sounds like you might not be focusing on trail braking. This still won't necessarily help the overslowing issue, but it changes your focus from "I need to come off the brakes smoothly because that's what I'm supposed to be doing" to "I need to come off the brakes smoothly because it's giving me more grip and helping me go faster". What is your current skill level? It may or may not be appropriate for you to start focusing on trail braking just yet.

Edit: I guess if you're mentioning instructors then you're probably still relatively new. I would still encourage you to look up some videos/reading material on trail braking and slowly start to incorporate it into your driving. It's not something you need to do at every corner, but there will be very obvious corners at every track where you can start practicing it and then you can take it from there.

I left foot brake on the DCT and without an instructor, prefer threshold braking to get most of it completed before turn in. It's over a second quicker in some corners, but it's not smooth. What I meant by applying throttle at the same time while still at 10-20% braking can be demonstrated by one of dogbone's videos -

When I do that, braking release is much smoother. But without it, I can't seem to get rid of the slight lurch forward when lifting off the brake pedal even half way to the apex. I think I'm at around 25% braking when I start slowly lifting after starting to turn in. Stretching out the 25% to 0% over a second or so results either in the lurch or overslowing. Just looking for any suggestions or tips as to what I could be overlooking. My caliper slide pins are dry, but clean. I may try a little bit of lube on them. Also using Motul RBF660 fluid flushed a week before the event, not that it should matter.

I need to get collect data somehow on my throttle and brake traces to get a better idea of what I'm doing as it's all just speculation on my part. I'll also need to revisit some of the suggestions from this thread about extended brake pedals to see if that helps as well. I had to place my right heel in front of my left foot to hold it in place and that just doesn't work well.

For reference, my fastest lap time with an instructor braking smoothly was 1:58.8xx and fastest solo time for one session I recorded when not braking smoothly was 1:53.7xx.

[rhyary]

Originally Posted by slicer

Are you running those sizes square? I thought you were using a 295 in the rear. That would be a lot of tire on a 9.5" wheel.

My recollection is that you are limited to 19" by your brakes. Do you have Brembo 380mm kit?

The topic is my front where I am looking for grip.

I don't have questions about my rear end :-)

[OG Shark]

Originally Posted by Ximian

The the local BMW CCA is now starting to use these standardized driver evals so it'll be useful to track this to see how it changes. My first two times at the track, I used the stock brake pads. There were comments about double braking or braking too early in the later sessions as the pads and rotors were starting to overheat, but nothing about smoothness. Once I switched to PFC 08 pads all around, the comments about double braking and inconsistent braking points stopped but braking smoothness on release became an issue. My instructor's goal for me was to improve braking smoothness by releasing the pad slower and later during the turn in, then getting on the throttle. I did manage to improve a bit and had a few corners where the release of the brakes was nearly perfect, but I can't do it without overslowing the car. Has anyone else dealt with a similar thing with stock brakes or is everyone else "cheating" and slowly getting on the throttle while still at 10-20% braking to mask the transition?

Is it possible that when you brake in the manner that you get a smooth release you have had more efficient braking --> leading to over braking by the time you fully release the pedal? So would it be a matter of adjusting your braking points once you can consistently release the brakes smoothly - can now brake later?

It certainly could be mechanical & I'm not saying that it isn't - but to me it sounds like it is technique based. If before you were working through inconsistent braking points - but now have found consistency there - it sounds like maybe now might need to work towards consistency in the braking technique to be able to figure out where the correct braking points need to be. To me unless you have consistent technique then knowing where the right braking point for you is becomes hard to gauge.

When running stock brakes -> PFC11 w/V3 DD -> AP Racing BBK I haven't come across having to "cheat" with the throttle to get a smooth transition. But that is a tool that can be used to help - but on this platform for me that is hard to do with the pedal locations. The brake is too far to the right for me to be able to comfortably & consistently left foot brake. I am working on this though...

Also are you upsetting the car when you do not get a "smooth" release?

[slicer]

Originally Posted by rhyary

The topic is my front where I am looking for grip.

I don't have questions about my rear end :-)

With all due respect, unless I'm misunderstanding, I'm seeing you mix and match odd tire sizes and completely different tire compounds. Pretty much all conventional wisdom advises against that. I'm trying to figure out why the heck you are doing that. Hoping to help you. Knowing your wheel limitations will help with that advice. If you want it....

Or at least better understand your logic - maybe I can learn something.

[dparm]

Originally Posted by Ximian

The the local BMW CCA is now starting to use these standardized driver evals so it'll be useful to track this to see how it changes. My first two times at the track, I used the stock brake pads. There were comments about double braking or braking too early in the later sessions as the pads and rotors were starting to overheat, but nothing about smoothness. Once I switched to PFC 08 pads all around, the comments about double braking and inconsistent braking points stopped but braking smoothness on release became an issue. My instructor's goal for me was to improve braking smoothness by releasing the pad slower and later during the turn in, then getting on the throttle. I did manage to improve a bit and had a few corners where the release of the brakes was nearly perfect, but I can't do it without overslowing the car. Has anyone else dealt with a similar thing with stock brakes or is everyone else "cheating" and slowly getting on the throttle while still at 10-20% braking to mask the transition?

I think it's going to be much easier to diagnose this with some telemetry. You can also mathematically infer the maximum cornering speed for a given radius and then compare your speed. That's a theoretical fastest speed and doesn't take certain things into account, but it would give you a frame of reference to push harder. I've been fortunate enough to get telemetry from similar cars to see just how much faster I can go.

My opinion on overslowing (which I sometimes do) is that it's related to a lack of confidence in the car's ability to corner. In other words, you are slowing down more than necessary because you don't think the car can make the corner at a higher speed.

A secondary cause might be that your line is incorrect. You think it's a slower (tighter) corner than it really is.


In some ways, I have always believed that overslowing is a symptom of being stuck in a novice mindset. I don't mean this disparagingly, by the way. What I am getting at is that when you are new to HPDE or autocross, they always drill this into your head:

1. Slow the car
2. Turn
3. Accelerate out of the corner
4. Repeat

There's so much happening on the track so people tend to get narrow focus on doing those things in the correct order. They get their braking done, then they turn, then once the turning is finished they get back on the gas. What takes more experience and confidence, and makes for a faster driver, is seeing that these three activities are not discrete. You can slow the car while you start to turn, and you can turn while you begin to accelerate. Unfortunately, the instructor is no longer in your car by that point, and you never really learn how to connect those activities together.


Based on what you are saying, it sounds like you may need to start braking a little bit later. I would slowly push the braking zone a bit later until you over do it and can't make the corner.

[dogbone]

Originally Posted by Ximian

What I meant by applying throttle at the same time while still at 10-20% braking can be demonstrated by one of dogbone's videos -

hmmm so----I don't left foot brake. But I guess that I'm switching between the pedals quickly enough that computer is showing them overlapping a bit.

Here is the CAN bus data chart of the gas (green) and the brake (red). They do look like they overlap just a bit (like in the first and last corners), but I promise I'm not left foot braking.

[rhyary]

Originally Posted by slicer

With all due respect, unless I'm misunderstanding, I'm seeing you mix and match odd tire sizes and completely different tire compounds. Pretty much all conventional wisdom advises against that. I'm trying to figure out why the heck you are doing that. Hoping to help you. Knowing your wheel limitations will help with that advice. If you want it....

Or at least better understand your logic - maybe I can learn something.

Thank you Slicer for trying to help.
So far the data does not support that mixing tires is detrimental to my goal of 1:36 at NYST.

What is important to get grip at the front.

Since the RR 295/30/19 has the grip and priced right, I don't have supporting evidence to spend more money at the rear, regardless what the conventional wisdom says.

The front is another story. So far the fastest tire is what conventional wisdom says should not work. It is too narrow. But it has the more rubber on the road, it is least expensive and is the fastest so far from all the combinations I tried. And the data explains why. While it is the narrowest I tried, it has the most contact patch.

The only larger contact patch for the front I can find is 245/35/19 Trofeo R. Still needs to be verified. It is a lot more expensive so for the money the results may not justified the cost.

The real difference would be the Hoosier A7.
If I can fit the 265/35/19 I am pretty sure the contact patch would be more than 223mm.

So the help I am looking for is about fitting 265/35/19 at the front. as a reminder, the 265/35/19 is the OEM ar the rear

[dparm]

Originally Posted by dogbone

hmmm so----I don't left foot brake. But I guess that I'm switching between the pedals quickly enough that computer is showing them overlapping a bit.

Here is the CAN bus data chart of the gas (green) and the brake (red). They do look like they overlap just a bit (like in the first and last corners), but I promise I'm not left foot braking.

It depends what the polling interval is. I suspect it's not fast enough to differentiate, based on that photo. Can you post a more zoomed in view? The X-axis maximum value is quite large, it looks like an entire lap all at once. Would be more interested in seeing just one segment at a time.

Something else that I like to overlay with gas/brake is steering wheel position. I call it my "inputs" graph.

[slicer]

Originally Posted by rhyary

Thank you Slicer for trying to help.
So far the data does not support that mixing tires is detrimental to my goal of 1:36 at NYST.

What is important to get grip at the front.

Since the RR 295/30/19 has the grip and priced right, I don't have supporting evidence to spend more money at the rear, regardless what the conventional wisdom says.

The front is another story. So far the fastest tire is what conventional wisdom says should not work. It is too narrow. But it has the more rubber on the road, it is least expensive and is the fastest so far from all the combinations I tried. And the data explains why. While it is the narrowest I tried, it has the most contact patch.

The only larger contact patch for the front I can find is 245/35/19 Trofeo R. Still needs to be verified. It is a lot more expensive so for the money the results may not justified the cost.

The real difference would be the Hoosier A7.
If I can fit the 265/35/19 I am pretty sure the contact patch would be more than 223mm.

So the help I am looking for is about fitting 265/35/19 at the front. as a reminder, the 265/35/19 is the OEM ar the rear

How are you determining your estimated contact patch?

[rhyary]

Originally Posted by slicer

How are you determining your estimated contact patch?

I measure the space between the rubber
Here is a cap 2 air gaps
Mich Cap 2 265/35/20
260mm - 15 -15 -15 - 5 = 210mm