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      03-02-2023, 01:08 PM   #22727
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Quote:
Originally Posted by Cmassey3 View Post
I noticed in the G8X track prep video, they specify to remove the water guards on the brake ducts before track use:



I checked on my E92 and it also has these duct rain guards with the same two screw removal. I'm going to try running without them on the track next session and see if that helps my front pad wear. At the moment, I'm wearing through the fronts (PFC 08) twice as fast as the rears. I'm running a stock car at the moment and this might help improve pad wear without going to GT4 style ducting.
Are you sure your E92 has the rain guards? I've been in the wheel wells several times and don't recall that. There is a cover for the headlight access, but that's high up.

My G80 gets filled with garbage and dead bugs because there's air intake ducts behind those covers. Removing them does reduce temperatures on track.
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      03-02-2023, 02:42 PM   #22728
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Quote:
Originally Posted by Cmassey3 View Post

I checked on my E92 and it also has these duct rain guards with the same two screw removal.
i dont even have that on my car anymore
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      03-02-2023, 03:13 PM   #22729
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Quote:
Originally Posted by Ximian View Post
Are you sure your E92 has the rain guards? I've been in the wheel wells several times and don't recall that. There is a cover for the headlight access, but that's high up.

My G80 gets filled with garbage and dead bugs because there's air intake ducts behind those covers. Removing them does reduce temperatures on track.
Based on this fender liner diagram, there's two potential spots it could be in the liner, either section 10 or section 16.

https://www.realoem.com/bmw/enUS/sho...diagId=51_5862

I haven't poked around yet to find out.
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      03-02-2023, 04:12 PM   #22730
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Quote:
Originally Posted by rhyary View Post
M1500Z

I want to see your throttle application vs location in the turn.

for example, if the high grip SC3R led you to brake later, not fully rotating your car, and lazy applying the throttle on exit as a result, it will add lap time. This is one example on what I am looking for.
I, too, had to stomp less on the brakes and lean on the tires more. Get the right PSI and all that (car in question seems pretty stiffly sprung, check damping too), ease into the pedal and smoothly enter the corner.

I gained a shit ton of speed doing this w/ the SC3Rs. I haven't had RE71Rs but I'm p sure this is a better tire. They're just weird about PSI. y'know typically heavier cars want higher PSIs, hence me saying unintuitive. I checked the ZL1 1LE manual and it recommended 26 cold. Strange

Last edited by chocstraw; 03-02-2023 at 04:18 PM..
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      03-04-2023, 08:48 PM   #22731
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Quote:
Originally Posted by rhyary View Post
M1500Z

I want to see your throttle application vs location in the turn.

for example, if the high grip SC3R led you to brake later, not fully rotating your car, and lazy applying the throttle on exit as a result, it will add lap time. This is one example on what I am looking for.

You wanted to know the difference between the two tires. I would want to start by looking at how you drove differently.

To make my point, if Sir L. Hamilton drove your car with SC3R vs you driving your car with 71RS, I am sure he will be quicker because he drives differently and the data would show how he drives differently.

Also, for 100w tires you have to generate more heat for them to be more stiky than 200tw tire. theoritically if you drove the same, you will have less traction with the 100tw tire.

It is a very complex topic. I have been down the tires rubbit hole for few years now.

Perhaps I can help.
Be honest now, how long did it take for you to learn this and did you get it explained via coaching or find out yourself (ie. sim, YT coaches etc)?

I see this all the time, taking too long to build peak brake pressure, killing the rotation ie. maintenance throttle is the no.1 laptime killer. So many myths in the paddock that make ppl slower. Before you know it, ppl are half a decade deep firing neurons that are harder to recoach/rewire. Pretty much equivalent to CBT.
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      03-05-2023, 08:42 AM   #22732
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gmx
I took me a long time to learn it.
Probably because I tend to be thick.

The short story is that I have invested in data logging from the start, I have been using professional coachig for me as the driver, I have been using professional suspension engineer coaching to understand the car, I have been experimenting with my 4-way JRZ settings and also many tires of many kinds.

Lastly, I have been doing 25-30 trackdays a year with many times open laps. I used that many trackdays to not be afraid to go slow if my setup is incorrect, but I invest time and effort in uderstanding why I was going slower. I use that knowledge to go faster the next time.

This, over time, allow me to understand what I was been told by professionals, and by my students.

I am well aware of what is being ďtoldĒ and from personal experience, at the beginning it was hard for me to translate into action what I was being told.

I have a good success with my students because I explain what needs to be done in a language and procedures that they can understand and implement.

I am not the best driver out there, I donít do racing or time attacks, yet I am not slow and with my mismatch 200tw tires hold the pace in the advance group.

I hope this answer your question
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      03-06-2023, 01:32 PM   #22733
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Quote:
Originally Posted by chocstraw View Post
I, too, had to stomp less on the brakes and lean on the tires more. Get the right PSI and all that (car in question seems pretty stiffly sprung, check damping too), ease into the pedal and smoothly enter the corner.

I gained a shit ton of speed doing this w/ the SC3Rs. I haven't had RE71Rs but I'm p sure this is a better tire. They're just weird about PSI. y'know typically heavier cars want higher PSIs, hence me saying unintuitive. I checked the ZL1 1LE manual and it recommended 26 cold. Strange
To attempt to tie a bow on this, I spent some time chatting and looking at data with rhyary and I think this is related to both of my issues of speed and wear. His theory which I believe has merit is that I'm loosing speed at entry by over-slowing, which leads to me not maintaining weight on the front of the car further into corners giving up mid-corner speed, and lastly getting on the throttle earlier to compensate and scrubbing the tires with oversteer on the exit. This aligns with with your saying chocstraw.

It makes sense and gives me some things to try in the future. I think I may have another weekend or so on those SC3 Rs, especially if I slow down a bit and work on getting the car rotated more during the entry/mid corner phase so I can unwind the steering more when getting back on throttle.
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      03-06-2023, 02:15 PM   #22734
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TLDR: trail braking is the answer
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      03-06-2023, 03:20 PM   #22735
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Quote:
Originally Posted by M1500Z View Post
To attempt to tie a bow on this, I spent some time chatting and looking at data with rhyary and I think this is related to both of my issues of speed and wear. His theory which I believe has merit is that I'm loosing speed at entry by over-slowing, which leads to me not maintaining weight on the front of the car further into corners giving up mid-corner speed, and lastly getting on the throttle earlier to compensate and scrubbing the tires with oversteer on the exit. This aligns with with your saying chocstraw.

It makes sense and gives me some things to try in the future. I think I may have another weekend or so on those SC3 Rs, especially if I slow down a bit and work on getting the car rotated more during the entry/mid corner phase so I can unwind the steering more when getting back on throttle.
I don't have a ton of track experience but I find myself usually having to pass most everyone in intermediate run groups. I'm just not keen on advanced groups which don't require point by passing. I'm outing myself here-- but yeah, I do think this is it. On blown EDC I was pulling like 1.4Gs. I didn't even have camber plates yet (lol @ my upgrade path).

Find a track with a corner with good runoff and just keep pushing the speed you're carrying into it. You'll continue to be surprised how much grip these have. Also suggest that 31-32 cold. It was just perfect set and forget.

I did just have an extremely experienced member from this community drive my car (owned 5+ and has driven dozens in all states of modification), he complimented it & said it was 'setup super well'.

I like this side of the forum because people here actually understand dynamics and handling. Tons of cars feel great under 70mph, around backroads, etc, but I think it was SYT that was talking about how true handling characteristics can't be determined even on the best of backroads, and most reviews of handling by non-track users should just be dismissed. It's that ~80mph+ area that handling starts to show itself or fall apart.

Last edited by chocstraw; 03-06-2023 at 04:32 PM..
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      03-06-2023, 03:41 PM   #22736
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Quote:
Originally Posted by leftfootbr8king View Post
TLDR: trail braking is the answer
Swing and a miss
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      03-06-2023, 04:37 PM   #22737
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Quote:
Originally Posted by DRLane View Post
Swing and a miss
Tight. Thanks for the helpful response.
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      03-06-2023, 04:38 PM   #22738
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Any different than TLDR: trail brake?
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      03-06-2023, 04:41 PM   #22739
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Quote:
Originally Posted by DRLane View Post
Swing and a miss
If read what 1500z wrote, can you tell me (this time without being a dick) that ďover slowing and not keeping weight on the front axleĒ isnít solved by trail braking?
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      03-06-2023, 04:53 PM   #22740
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Quote:
Originally Posted by DRLane View Post
Any different than TLDR: trail brake?
I think so? I summed up what he was saying into a driving skill that has a name.
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      03-06-2023, 04:53 PM   #22741
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Quote:
Originally Posted by leftfootbr8king View Post
If read what 1500z wrote, can you tell me (this time without being a dick) that ďover slowing and not keeping weight on the front axleĒ isnít solved by trail braking?
Iím not being a dick, just responding with the same single statement tone. No, you did not understand the post and responded with a ďtoo long didnít readĒ contribution that wasnít even correct.

Overslowing doesnít have anything to do with trailing off the brakes. Heís coming into the corner too slow and thus the trailing the brake further to try and load the front tires isnít applicable.

Itís very clear in his post. Give it another read and we can find some more examples if needed.
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      03-06-2023, 07:33 PM   #22742
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I guess if you define trail braking as simply ďtrailing off the brakesĒ in a straight line then sure, thatís not the solution.

How I was taught, understand and practice trailbraking is more of a comprehensive approach to cornering.


In his situation, if I were over slowing corners and having to get on the throttle too early thus creating a situation where I didnít have enough weight over front tires to rotate the car Iíd first move my braking zone a little deeper, to make sure I didnít over slow. In an early apex corner that might be all that is needed. In a corner with a later apex I would include trailing off the brakes to mid corner to rotate the back end a bit while keeping weight over the front tires. Done correctly when itís time to apply some throttle the wheel wonít be pinched.
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      03-06-2023, 07:43 PM   #22743
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Quote:
Originally Posted by leftfootbr8king View Post
In his situation, if I were over slowing corners and having to get on the throttle too early thus creating a situation where I didn’t have enough weight over front tires to rotate the car I’d first move my braking zone a little deeper, to make sure I didn’t over slow. In an early apex corner that might be all that is needed. In a corner with a later apex I would include trailing off the brakes to mid corner to rotate the back end a bit while keeping weight over the front tires. Done correctly when it’s time to apply some throttle the wheel won’t be pinched.
I would generally agree with this, but add that there is an inverse correlation to steering angle such that as you reduce brake pressure, you are able to increase steering angle.
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      03-06-2023, 07:48 PM   #22744
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Quote:
Originally Posted by okusa View Post
I would generally agree with this, but add that there is an inverse correlation to steering angle such that as you reduce brake pressure, you are able to increase steering angle.
Yes. 100%.
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      03-06-2023, 07:57 PM   #22745
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Quote:
Originally Posted by leftfootbr8king View Post

In his situation, if I were over slowing corners and having to get on the throttle too early thus creating a situation where I didnít have enough weight over front tires to rotate the car Iíd first move my braking zone a little deeper, to make sure I didnít over slow.
I would disagree with this approach. For 99% of people, this will result in overbraking, late turn-ins, and further overslowing. The more comfortable approach of keeping the same braking zone, but reducing the brake pressure is better because it's less drastic load transfer to deal with/smooth out.

Quote:
In an early apex corner that might be all that is needed. In a corner with a later apex I would include trailing off the brakes to mid corner to rotate the back end a bit while keeping weight over the front tires. Done correctly when itís time to apply some throttle the wheel wonít be pinched.
I don't like these generalities because they apply to idealized, simple corners where people don't usually struggle. Real corners that are tricky are more nuanced, requiring a specialized approach. I can find plenty of exceptions to these suggestions, so they're not worth repeating without discussing a specific turn.
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      03-06-2023, 08:16 PM   #22746
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Quote:
Originally Posted by Ximian View Post
I would disagree with this approach. For 99% of people, this will result in overbraking, late turn-ins, and further overslowing. The more comfortable approach of keeping the same braking zone, but reducing the brake pressure is better because it's less drastic load transfer to deal with/smooth out.
My response was based on this being the track forum and the assumption that anyone interested in this approach is, like me, seeking the fastest possible way through a corner. In other words, the opposite of what may be the more comfortable approach. I think it is universally accepted that this is the fastest approach and one that anyone seeking faster lap times should be practicing.
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      03-06-2023, 08:29 PM   #22747
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Ross Bentley would disagree with you.

Just because 99% of people canít trailbrake a corner effectively doesnít mean they shouldnít try.
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      03-06-2023, 08:30 PM   #22748
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Quote:
Originally Posted by okusa View Post
My response was based on this being the track forum and the assumption that anyone interested in this approach is, like me, seeking the fastest possible way through a corner. In other words, the opposite of what may be the more comfortable approach. I think it is universally accepted that this is the fastest approach and one that anyone seeking faster lap times should be practicing.
What approach exactly?

I've only been instructing for about a second and a half so my anecdote isn't worth anything, but I've never seen anyone successfully execute "you're overslowing for corner X, brake later this time to prevent it." I'm sure there are quite a few people out there that will get it right away, but most people will first need to take a step or two backwards. Thus the "comfortable approach" of reducing brake pressure over the same braking zone which will be significantly faster than what they were doing previously.

Braking later to fix overslowing is like saying "you're doing this wrong, have you tried doing it correctly?" It doesn't actually help because it doesn't address why it's happening. We can certainly discuss what the root causes of overslowing tend to be, what experience level they affect most, and why giving those people another problem to deal with (heavier braking, more load transfer to and from the front axle to smooth out for turn-in) isn't going to be as helpful.
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