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      01-11-2022, 02:49 PM   #903
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Quote:
Originally Posted by admranger View Post
Pushed it all the way to 11.
Well, tbf you have to press it hard enough to trip the auto kickdown button. So on one hand Iím like damn nice press dude.
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      01-12-2022, 08:41 AM   #904
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ITT: no one shares the epiphany of when they turned off DSC/MDM/TCS and suddenly went 2 seconds faster

I guess I'll be the first.
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      01-12-2022, 04:20 PM   #905
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I have a new BMW_PT6-test2 from AIM that I need volunteers with AIM device connected via CAN bus.

Unlike the DCT temp, I need volunteers that can drive their cars for the test and send me back export of the session.

I will program the display with the new variables we are testing so that you can see what we are testing.

However, I will need export of the session sent back to me. Some of the variables are raw numbers that AIM may have to massage in order to make them useful.

For example, the number that comes out of the DS RPM may not be useful raw, but with the right formula it can be the DS rpm.

Many thanks in advance for those willing to help out in this process.

Contact me via PM or rhyary@gmail.com
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      01-12-2022, 06:02 PM   #906
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Quote:
Originally Posted by rhyary View Post
Thank you.
Feel free to give me a hard time on the DSC status variable
haha what? Why would I give you a hard time about it? I donít even know what that is!!!
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      01-15-2022, 06:26 AM   #907
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More tires.

I have 10 Car Clinic Control events this season with SCDA at LRP. Their day is structured as half days. They do CCC 9-12 and big track 1-5.

This year I am taking the CCC seriously and therefore will be doing just the CCC in the morning and will be working with my private students in the afternoon without going on the big track with my own car.

So I was on a hunt for cheap tires for CCC. This came on my search and should do for the purpose. And same tires front and rear because I like to mix up my experiences.

265/35R-19 DUNLOP SIGNATURE HP SL
275/35R-19 DUNLOP SIGNATURE HP SL

Total cost shipped to me is $510 or $138/tire

One wonders how many CCC I can do on these.
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      01-15-2022, 08:57 PM   #908
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Judging from the tread design, I think those will overheat and chunk pretty fast. I'd be checking wear very closely after each session.
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      01-15-2022, 09:24 PM   #909
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Cheaper the better for CCC. The CCC will be awesome for you! You’ll be powersliding over the hill at LRP soon enough!
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      01-16-2022, 06:43 AM   #910
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Quote:
Originally Posted by dparm View Post
Judging from the tread design, I think those will overheat and chunk pretty fast. I'd be checking wear very closely after each session.
Do you mean the tread be torn a part rather than used up quickly?

The CCC has two parts, an autocross like course and watered skid part.

It is happening on the upper deck of LRP
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      01-16-2022, 11:10 AM   #911
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I got back a session from Solo2DL and we have a big win with DCT Temp and Drive Shaft RPM.

bunch of torque values came back 0
few trq values returned the same number, but not sure what it means or how to use.

I think DS RPM can be useful when comparing to rear wheel speed and gps speed. but it is too early to think about it.

Session has been sent to AIM for analysis
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      01-17-2022, 06:18 PM   #912
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Quote:
Originally Posted by rhyary View Post
Do you mean the tread be torn a part rather than used up quickly?
I've had this happen on a Toyo 888 at Phoenix International Raceway (roval course). New tires and the tread just ripped off on the RF due to the banking. Pressures were good but there was just too much tread for the load.
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      01-21-2022, 01:43 PM   #913
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F80 hubs and studs.

So I started the hub improvement using Future Classic F80 threaded M14 studs.

I then sent the front FC F80 hubs to Core4 and converted to pressed studs.

Then my front driver hub bearing went bad, so Core4 sent me a F80 hub for pressed studs (with no studs) and I moved the used studs to the new hub. One had a bad thread and I replaced it with a spare.

This winter I got from Core4 a new F80 hub with studs already pressed in for the front passenger. and 5 more studs to replace the used ones on driver side.

So I will be starting the year with new hubs and studs on the front. A used hub as spare. and bunch of used studs as spares.

The rears still have the threaded FC F80 M14 studs and hubs. This will be replaced in the future with pressed studs. the problem with the rear is that you can't take them off and have spares. Taking them off destroy the bearings. As I understand it.

So step one will be to get the rears from Core4 into inventory then decides when to replace the rear.
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      01-27-2022, 07:09 AM   #914
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All AIM-sters,

I asked AIM support to separate the effort for DCT Temperature from the DSC Status and ABS Status.

The DCT Temperature will be moved from a test location on CC36 into the original location CC05.

When you update your BMW_PT6 protocol, the expected behavior is that DCT TMP will magically start working.

This will be thru the normal RS3 studio update procedure. If anyone needs help with that, let me know.

I will then separately work with them on other new variables we have like Drive Shaft RPM and few others

Lastly, this is all happening because ///Mobbin.

I can't thank him enough for his initiative.
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      01-27-2022, 10:45 PM   #915
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Quote:
Originally Posted by rhyary View Post
All AIM-sters,

I asked AIM support to separate the effort for DCT Temperature from the DSC Status and ABS Status.

The DCT Temperature will be moved from a test location on CC36 into the original location CC05.

When you update your BMW_PT6 protocol, the expected behavior is that DCT TMP will magically start working.

This will be thru the normal RS3 studio update procedure. If anyone needs help with that, let me know.

I will then separately work with them on other new variables we have like Drive Shaft RPM and few others

Lastly, this is all happening because ///Mobbin.

I can't thank him enough for his initiative.

Great work! I wonder how manual temperatures show up. I would love that too
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      01-28-2022, 03:03 AM   #916
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They changed the name to DCT Temp.
They also added DS rpm
and few other variables related to the DCT.
Although we did not test those enough.

Make sure you clone the config you have working and make changes to the clone and test.
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      01-29-2022, 09:00 AM   #917
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Ever wondered where/when/for how long your ABS is being activated?

Analysis of my data on a wet day at WGI revealed a very interesting information.

On second 46-47 I was coming into the bus stop (inner loop) on a wet day at WGI.

46.00sec
BRAKE PRESSURE 410-420
LF, FR, RL, RR all on 410-420 psi

46.14sec
LF 438
FR 326
RL 280
RR 280

46.26sec
FL 414
FR 319
RL 206
RR 200

Now the interesting part is that BRAKE PRESS stays the same roughly the PSI of the wheel with the most pressure. In this case BRAKE PRESS stays the same ~400-410 psi

BRAKE PRESS measures what the driver is doing.
The individual wheels called "BRK_FL_PRESS" report what the car is doing. (FL, FR, RL, RR)

The the above was sampled at 10Hz.
I bumped the frequency to 20Hz to get more granular data. I read some place that the ABS can pulse at 30 times per second. If that the case AIM should update their option to allow 30Hz. Currently 20Hz is the fastest option.
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      01-31-2022, 08:22 AM   #918
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Frequency

You want to know when ABS is active to understand threshold braking. You don't have to. You have ABS to do the work for you. But… if you want to.

The active ABS indication is not just fluid pressure. The car is smart enough to distribute pressure without activating the ABS.

Fundamentally, If the car distribute more pressure to corner(s) and does not activate the ABS, you have more braking.

If, however, you press the brakes more than available traction, in the E92 M3 - per individual wheel, the ABS will release pressure and apply pressure again. It can do that 20 to 30 times per second. I did not find the spec so I am making a generic assumption per google search on ABS function.


The AIM derive function
AIM function deriv() allows you to take value and the result will be value per second. This also called velocity

If I create a math channel deriv(BRAKE PRESS) I will get the changes per second on that BRAKE PRESS aka brake velocity

The BRAKE PRESS CAN channel looks like gives the pressure the driver is requesting from brake system.

deriv(BRAKE PRESS) provide how quickly you applied the brake pedal.

Coming into WGI bus stop in torrential rain at time 45.740sec (45 sec and 74 hundreds) I applied 130 psi pressure at a rate of 1413 psi per second

Brake velocity at the wheel was
LF 310
RF 516
LR 350
RR 350

According to the data, I applied the brake pedal at a faster rate the the psi changed at the wheel.

Here comes the interesting part:
during the next .5 second the velocity changed.

While I continued to request more brake (psi going from 120 to 230) the rate at which I was asking went down from 1400 to 532.

What happened at the wheels was a different story

At time 45.944
BRAKE PRESS velocity was 537

LF 1305
RF 681
LR 1055
RR 1139

Now comes the question. In your opinion, which wheel had the most mount of traction?

Note!
Please don't include the whole lengthy explanation. just answer what you think to keep it short.
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      01-31-2022, 08:23 AM   #919
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Knowing which wheel has best traction can be useful for selecting a line on the track with best traction.
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      01-31-2022, 08:44 AM   #920
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Left front had the most traction.

Are you analyzing at this level while using MDM?
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      01-31-2022, 10:37 AM   #921
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Quote:
Originally Posted by roastbeef View Post
Left front had the most traction.
Nope. why do you think LF?

Remember brake velocity is how many times per second the pressure is changing

And, why would the pressure at the wheel will change per second compares to the requested by the driver pressure
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      01-31-2022, 12:08 PM   #922
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Quote:
Originally Posted by rhyary View Post
Nope. why do you think LF?

Remember brake velocity is how many times per second the pressure is changing

And, why would the pressure at the wheel will change per second compares to the requested by the driver pressure
He probably thought the bottom numbers were referring to brake pressure.
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      01-31-2022, 12:32 PM   #923
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Quote:
Originally Posted by Bartledoo View Post
Quote:
Originally Posted by rhyary View Post
Nope. why do you think LF?

Remember brake velocity is how many times per second the pressure is changing

And, why would the pressure at the wheel will change per second compares to the requested by the driver pressure
He probably thought the bottom numbers were referring to brake pressure.
Yeh, it is confusing and highly guesstimate work.

I wish I had direct access to the all the computers in the car so I don't have to guess what the car is doing.

I hope to validate my thinking while sampling at 20Hz.
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      01-31-2022, 04:45 PM   #924
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I guessed left front because you're going to load the outside front tire heading into the bus stop. It's going to be pressed to the ground the most, but it will also be the first to lose grip if you overcook it.

If you're doing this with MDM, it's might screw up your numbers, since it mostly uses the front brakes. Although I'm not entirely sure what you're trying to accomplish with these numbers. It's also going to override what you're asking the car to do.
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