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      09-24-2020, 06:36 PM   #397
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Quote:
Originally Posted by Bartledoo View Post
Your temps and wear, particularly inside on the front inside tire, may be from excessive understeer. I get the same thing on the inside rear from excessive oversteer.
Temp across the tire reflects the tire contact patch. What to do about is perhaps more art then science since it is about compromises and achieving a balance that, hopefully, yield better lap time, or better longevity.

Since I don't have access to suspension engineer, I am left to my own adjustments. All I can do is experiment report back results. good or bad.
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      09-24-2020, 08:24 PM   #398
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Quote:
Originally Posted by rhyary View Post
Temp across the tire reflects the tire contact patch. What to do about is perhaps more art then science since it is about compromises and achieving a balance that, hopefully, yield better lap time, or better longevity.

Since I don't have access to suspension engineer, I am left to my own adjustments. All I can do is experiment report back results. good or bad.
Exactly, excessive understeer drags the inside front across the surface at angle much greater than the static camber.
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      09-25-2020, 09:20 AM   #399
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2020 HPDE season

I would love to have a technical discussion with someone on the subject.

But from observation, and keeping track, and lots of experimenting with differrnt size tires and camber at -1.8, -2.0, -2.5, -3.0, and now -3.5:

With 265/35/19 R7, it generate so much grip, that the -3.5 was very beneficial.

However, with the max performance tires 265/35 or 285/30 they will understeer. I am working on minimizing the understeer, but it will be there and it needs to be manage.

-3.5 static camber does effect braking and the inside tires. Both the outside wheel and the inside wheel.

Specifically, If I am on 1:37 pace at NYST, I am getting good temperature on the tires, but they will get hot and will start understeer. So if I slow down to 1:38-1:40 pace (because I have to) the inside will get hotter than the outside on both the inside and the outside.

There is another factor to mention. At front 38psi hot the tire cary the front well, but the outside tire will be cooler than the inside. At 35psi hot, the temps are more even, but the front is squishy and not necessarily better grip. At least my lap times are not better.

It makes me think that this is a very complicated subject and I am sure professional teams have a lot of instrumentation and knowledge to make decisions. In addition, they can adjust the suspension during a race based on data and expertise.
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      09-25-2020, 03:26 PM   #400
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Quote:
Originally Posted by rhyary View Post
It makes me think that this is a very complicated subject and I am sure professional teams have a lot of instrumentation and knowledge to make decisions. In addition, they can adjust the suspension during a race based on data and expertise.
Bingo. You are only one person and don't have the time or know-how to do complex car setup. There is also not one setup that will be perfect everywhere, it's all about compromises. Just look at the insane amount of tiny changes F1 cars get every weekend.

As I had said earlier in this thread, there's a reason a lot of people seem to use similar setups -- they're proven to be a good compromise that doesn't need constant fiddling. 3-way and 4-way suspension setups are a rarity for weekend folks like us.

The other side of this is developing the skill to adjust your driving based on the car's feedback and the available traction. If the front tires are overheating or whatever, then you need to adjust your turn-in and steering inputs to keep that under control. If the track is wet, you don't drive the same way as when it's dry, right? Same idea.
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      09-26-2020, 09:27 AM   #401
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This is not "arguing" my position. I am not trying to be right here. I am just sharing my opinion and explain my rational.

One person "fiddling" is another person "fine tuning".

I enjoy fine tuning, others don't like to fiddle.

I enjoy options to fine tune (4-way) others wants to be told what to do (1-way or 2-way set it and forget it)

In my profession, I make a living and appreciated for fine tuning. It carried over to my hobbies.

What does it all mean? If I over heat the inside of the tire, I can chose to go slower, not a bad choice, or I can chose to change the alignment and check the data. If I got it wrong, I put it back to -3.5.

All through the process, I my knowledge doesn't stay the same. I get enriched by the experiences and not only I understand more on my own, I understand better what others are telling me. The combination is making me a better driver. My learning process perhaps is slower because it takes time to understand how 4-way shocks work and what each click means, but at the end I understand better what each function does.

For example, The JRZ 4-Way is a bit different. It has 1 rebound and 3 damping settings.

The three damping are HS and LS on the canister and the third one is on the shaft and it controls the little imperfections in the road during the turn. So the HS controls the obvious bumps, the LS controls how quickly the HS works and the shaft control the imperfections of the road.

It took me many track days to understand and feel the effect of those adjustments. But now I do. And I can actually change the settings at the track based on how I feel the conditions are.

I know not only what each control does, but I can feel 1 click differences. This will not make me faster this year, when I am regularly change tires. However, IMO, it will make me faster next year when I limit my tires selection and suspension components.

So, what I do this year make me faster this year, obsoletely not. But will it make me faster, more in control of available traction, better manage the tires? I believe that yes, it will make me faster and more importantly it will reduce my risk at higher speeds.

This is the theory anyway. Only time will tell if I am right.
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      09-26-2020, 05:50 PM   #402
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Rear JRZs are ready for install with pots mounted.

Picture courtesy of Autocouture.
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      10-03-2020, 08:40 AM   #403
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I just had this surreal experience at nicksm3 trackday at NYST.

I was on my rear RR 295/30/19 third day and front RE050A 285/30/19 second day.

I brought with me new sticker 265/35/19 MPSCup2 as spare. These are nice as spare because I can mount them on either front or rear to come home. Alas, I am saving them for Lime Rock on Oct 24th. I already established that any soft tire is not economic to run at NYST because the surface is abrasive.

Anyway, this Oct 1st trackday was open track, perfect dry 60 degree sunny day. I have just gotten my rear JRZ back from rebuilt.

So every thing was perfect to tune the rebound and compression. I started with what worked on the front and set the rear to be the same.

So started the day on:
Front: Rebound 15, shaft 15, canister HS 15, LS =5
Rear : same

Car was understeering at 1:38-1:39 pace and not that happy. Since I have the pots mounted I drove when the GS display on the pots page and was looking at the pots movement in mm. Not in mm/s.

My max healthy movement at the front is -30mm (full compression) and 30mm (full extension) using a 75mm pots

Rear -60 compression and 60mm extension using 120mm pots

The GS display showed too much movement and I felt the car roll too much at the fast turns 8-9-10 sequence.

The format of the day allowed me to make adjustment, drive few laps and come off for few more laps. Rinse and repeat.

To make a long story shorter, I arrived to a happy car setup as such
Front HS 16
Rear Rebound +1 to 16, Compression +2 to 17.

The car was still understeering at the slow corners but felt great at the fast turns.

I also tried to bring hot PSI on the front to 38, but got at back to 35psi.

At NYST the passenger side works the hardest. Temp on the rear passenger RR were uniform across and over 150. We took the rear camber from -2.2 to -2.0 and I was curious to see if the inside will overheat less. According to the RR spec it can go up to 220 deg. So perhaps I was not getting enough temp into it, but my front was the issue anyway.

The front passenger was uniform close to 160deg and it was a good because I took the camber from -3.5 to -3.4. so the 285 was not rubbing the fender, and temp were still uniformed across.

The only fly in the otherwise perfect day is that the RE050A was understeering as the day progressed and the pace of 1:38-1:40 was not as fast as the first day on that tire.

Wear was excellent and after two days I can definitely go a third day on it. Alas, I will not breaking lap records. Still 1:38-1:39 is a fast enough pace.

Some may say that "understeer?" make the front soft. Well that was not possible because making the front soft was not good for the fast corners and I am not sure it would have helped in the 45-50mph corners.

Here is where the surreal experience started.

Toward the end of the day I could not just know that I have a brand new sticker Cup2 sitting there and not give it a try. I mounted the Cup2 to just see what its like.

The front grip was out of this world. I just turned the wheel and the car front went exactly where I wanted it to go. It had so much grip that the car was oversteering like crazy.

To make a long story shorter, I had to add Front HS +1, took the rear -1 on rebound, took the rear HS to 6 from 16 (6 is my comfort road settings) and that stabilized the car at 1:40 pace.

The ease and the relaxed way the car was doing 1:40 was so strange. I was not going fast on the straight at all, mild braking, and the car was doing 1:40 like it was nothing.

Now there is economic downside to this experience. Even at the slow pace of 1:40 the amount of rubber that came off the Cup2s was astonishing. I am glad I only tried this end of the day.

So there you have it, while Cup2 has great grip, it and the R7/A7 and the Corsa 60 tread are all great tires on the front, but not possible to use unless you own a tire company.
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      10-04-2020, 07:38 AM   #404
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Quote:
Originally Posted by rhyary View Post
I just had this surreal experience at nicksm3 trackday at NYST.

I was on my rear RR 295/30/19 third day and front RE050A 285/30/19 second day.

I brought with me new sticker 265/35/19 MPSCup2 as spare. This are nice as spare because I can mount them on either front or rear to come home. Alas, I am saving them for Lime Rock on Oct 24th. I already established that any soft tire is not economic to run at NYST because of how abrasive is the surface.

Anyway, this Oct 1st trackday was open track, perfect dry 60 degree sunny day. I have just gotten my rear JRZ from rebuilt.

So every thing wad perfect to tune the rebound and compression. I started with what worked on the front and set the rear to be the same.

So started the day on:
Front: Rebound 15, shaft 15, canister HS 15, LS =5
Rear : same

Car was understeering at 1:38-1:39 pace and not that happy. Since I have the pots mounted I drove when the GS display on the pots page and was looking at the pots movement in mm. Not in mm/s.

My max healthy movement at the front is -30mm (full compression) and 30mm (full extension) using a 75mm pots

Rear -60 compression and 60mm extension using 120mm pots

The GS display showed too much movement and I felt the car roll too much at the fast turns 8-9-10 sequence.

The format of the day allowed me to make adjustment, drive few laps and come off for few more laps. Rinse and repeat.

To make a long story shorter, I arrived to a happy car setup as such
Front HS 16
Rear Rebound +1 to 16, Compression +2 to 17.

The car was still understeering at the slow corners but felt great at the fast turns.

I also tried to bring hot PSI on the front to 38, but got at back to 35psi.

At NYST the passenger side works the hardest. Temp on the rear passenger RR were uniform across and over 150. We took the rear camber from -2.2 to -2.0 and I was curious to see if the inside will overheat less. According to the RR spec it can go up to 220 deg. So perhaps I was not getting enough temp into it, but my front was the issue anyway.

The front passenger was uniform close to 160deg and it was a good because I took the camber from -3.5 to -3.4. so the 285 was not rubbing the fender, and temp were still uniformed across.

The only fly in the otherwise perfect day is that the RE050A was understeering as the day progressed and the pace of 1:38-1:40 was not as fast as the first day on that tire.

Wear was excellent and after two days I can definitely go a third day on it. Alas, I will not breaking lap records. Still 1:38-1:39 is a fast enough pace.

Some may say that "understeer?" make the front soft. Well that was not possible because making the front soft was not good for the fast corners and I am not sure it would have helped in the 45-50mpg corners.

Here is where the surreal experience started.

Toward the end of the day I could not just know that I have a brand new sticker Cup2 sitting there and not give it a try. I mounted the Cup2 to just see what its like.

The front grip was out of this world. I just turned the wheel and the car front went exactly where I wanted it to go. It had so much grip that the car was oversteering like crazy.

To make a long story shorter, I had to add Front HS +1, took the rear -1 on rebound, took the rear HS to 6 from 16 (6 is my comfort road settings) and that stabilized the car at 1:40 pace.

The ease and the relaxed way the car was doing 1:40 was so strange. I was not going fast on the straight at all, mild braking, and the car was doing 1:40 like it was nothing.

Now there is economic downside to this experience. Even at the slow pace of 1:40 the amount of rubber that came off the Cup2s was astonishing. I am glad I only tried this end of the day.

So there you have it, while Cup2 has great grip, it and the R7/A7 and the Corsa 60 tread are all great tires on the front, but not possible to use unless you own a tire company.
Nice write up and driving!
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      10-05-2020, 08:41 AM   #405
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I don't care what "treadwear" rating the tire has. The RE050 and Cup2 aren't even close the same level of tire. I'm not surprised at all even with the narrower size on Cup2.

I know it seems to work for you but I can't fathom running so many different tires in sizes, compound, etc as you do and not having a car that feels so different every time.

Why not just stick to something reasonably common and continue to develop the car around it?

Do you have 380mm Brembos or something that has you stuck on 19" tires too?


I picture this going on in your brain every time you make some kind of tire/size/compound change

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      10-05-2020, 11:50 AM   #406
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I enjoy testing all the combinations.
The goal for 2020 was not to develop the car but experience all the different ways I CAN develop the car in the context of cost

The question is not whether Cup2 is better, the question is "is it better at twice the cost"

And I found out that no, the Cup2 is not reasonable cost at NYST, but it is at LRP.

Is 265/35 Cup2 that much better at LRP than the 285/30 PS91 given almost half the cost?

Will find out on the 24th
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      10-12-2020, 01:55 AM   #407
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Stats
Date: Oct 11 2020
Organization: Dynosaurs
Track: Palmer Motorsport Park
Weather: Dry

Tires Front: FFI500 2015
275/30/19 day 1

Tires Rear: Ecsta V720 2017
275/35/19 day 3

Time: 1:50.94
PB - second day at Palmer.
Previous PB 1:59.06

Comments:
Car felt great. I was surprised how well the 275 performed.


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      10-12-2020, 09:18 AM   #408
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Jeez, not a lot of run off there. Make a mistake and you're in the wall.
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      10-12-2020, 09:35 AM   #409
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Jeez, not a lot of run off there. Make a mistake and you're in the wall.
It is built into a mountain side.
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      10-24-2020, 06:35 AM   #410
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Heading out to LRP today.
Car felt terrific at Palmer, the weather is good and I signed up to both groups Intermediate 2 and Advance.

I am on a good set of tires, MPSS 295/30/19 on the rear with one trackday on it and sticker Ecsta PS91 285/30/19.

Should be a good day
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      10-24-2020, 05:38 PM   #411
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Personal Best at LRP 60.9
very comfortable now & 1:01
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      10-25-2020, 10:27 AM   #412
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Stats
Date: Oct 24 2020
Organization: SCDA
Track: Lime Rock Park, CT
Weather: Drizzle first two sessions. Dry last two session. 4 x 40min

Tires Front: Ecsta PS91 stickers 2020
285/30/19

Tires Rear: MPSS 2016
295/30/19 day 2

Time: 60.9 seconds (PB)
Many laps on 1:01.x
Previous PB 1:01.x on slicks

Comments:
What can I can I say, it was a great day.
I need to find another 1sec some place.
Chasing a Corvette, Two E92 M3 getting in the way, finally had to pass them. I was behind them few times, and talked to the drivers in the paddock before this session so I was comfortable with not waiting for the point-by

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      10-27-2020, 11:20 AM   #413
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Here is a good example of a car in the advance group that I could not keep up with on the turns.
E36 - Reminded me Thundermoose AiM 60sec traces (that he sent me)

Photo credit: Shawn Pierce Photography
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      10-27-2020, 12:35 PM   #414
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Quote:
Originally Posted by rhyary View Post
Here is a good example of a car in the advance group that I could not keep up with on the turns.
E36 - Reminded me Thundermoose AiM 60sec traces (that he sent me)

Photo credit: Shawn Pierce Photography
He's probably running four of the same tires 🤣.

Kidding, nice video!
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      10-27-2020, 03:55 PM   #415
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Quote:
Originally Posted by DRLane View Post
He's probably running four of the same tires 🤣.

Kidding, nice video!
HAHAHAH. Zing!
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      10-28-2020, 07:40 AM   #416
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Quote:
Originally Posted by DRLane View Post
Quote:
Originally Posted by rhyary View Post
Here is a good example of a car in the advance group that I could not keep up with on the turns.
E36 - Reminded me Thundermoose AiM 60sec traces (that he sent me)

Photo credit: Shawn Pierce Photography
He's probably running four of the same tires 🤣.

Kidding, nice video!
Thanks for watching my videos.

Yes, all same Hoosier tires. We already know they are fast and expensive. So while I was doing two trackdays in one, 40 min every hour, he was doing 20min every hour. My cost was lower for twice the track time.

What my 2020 thread is documenting is that going on tires half the price of the conventional wisdom like MPS4S or even RE71 let a long R7/A7 is an acceptable way to control trackday cost which allows for virtual couching like Racers360, or adding track time.

I am not claiming to know anything, I am just a computer consultant guy that made good living questioning conventional wisdom (which is driven by hardware manufactures and resellers). Conventional wisdom turns out is not that innocent.

But at the end of the day, if you want to win races and time attack competition, there is no substitute for real slicks like R7/A7.
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      10-28-2020, 09:27 AM   #417
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Good job Ramy. I see a significant improvement in your driving skills.
And that is a result of a lot of track time I think. 40 min every hour is a lot of track time in one day.
I bet you can brake 1 min at LRP with A7 hoosiers.
At all 4 corners of course
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      10-28-2020, 10:05 AM   #418
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Quote:
Originally Posted by rhyary View Post
Quote:
Originally Posted by DRLane View Post
Quote:
Originally Posted by rhyary View Post
Here is a good example of a car in the advance group that I could not keep up with on the turns.
E36 - Reminded me Thundermoose AiM 60sec traces (that he sent me)

Photo credit: Shawn Pierce Photography
He's probably running four of the same tires 🤣.

Kidding, nice video!
Thanks for watching my videos.

Yes, all same Hoosier tires. We already know they are fast and expensive. So while I was doing two trackdays in one, 40 min every hour, he was doing 20min every hour. My cost was lower for twice the track time.

What my 2020 thread is documenting is that going on tires half the price of the conventional wisdom like MPS4S or even RE71 let a long R7/A7 is an acceptable way to control trackday cost which allows for virtual couching like Racers360, or adding track time.

I am not claiming to know anything, I am just a computer consultant guy that made good living questioning conventional wisdom (which is driven by hardware manufactures and resellers). Conventional wisdom turns out is not that innocent.

But at the end of the day, if you want to win races and time attack competition, there is no substitute for real slicks like R7/A7.
Yes Ramy, your tire philosophy for 2020 is very well documented. I was just poking a little fun. I'm all about cost effective seat time myself.
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