HPDE experiments, results and observations

[rhyary]

On Thursday, I was coaching two students at Lime Rock Park, and I had the opportunity to drive two cars.

The first car was a 2008 Cayman 987, which was stock and equipped with MPSS tires. The car felt great, but I wasn't very familiar with the traction control options on that particular model. The owner had left the traction control as it was. However, during my drive, I noticed that it was interfering too much throughout most of the lap. As the MPSS tires heated up, the traction control was constantly fighting against the tires, especially during 65-second laps. Later, when I was at home, I discovered that turning off the traction control option doesn't completely disable it. It seems that a more suitable option for the track would be to disable it knowing that it is still there for emergencies. In contrast, the 987.2 Cayman Cup car I've been driving has a "Sport+" option, and the traction control hardly comes on, if at all, but I know it is not completly off.

The other car I had the chance to drive was a 2020 Hyundai Veloster N. I was told that the "N" version was designed by an engineer who had previously worked on the BMW M2, and Hyundai hired him to create a sport version of the Veloster.

It was my first time driving a front-wheel-drive car on a race track, so it was a nice experience to try something different. The Veloster N is equipped with a turbocharged engine, but I found that the turbo lag was much less noticeable compared to the M2 and F80 M3/M4 I had driven earlier this year.

As for my own driving opportunities, my engine installation is scheduled for the week of June 26, so currently, I only have limited driving opportunities, mostly relying on the crumbs I get from my students.

[rhyary]

Interesting presentation

https://youtu.be/ybo49E68b-4

[rhyary]

I came back from 4 days at WGI watching the IMSA races. I took an 'active' approach to watching. I walked to a number of turns and paid close attention to where the PRO drivers turn in, when and where they exit. I carefully listened to when they added throttle and how much. WGI allows you to stand pretty close to the action, so if you observe with all your senses, you can see and hear when and how much throttle they use. After a while, you can start to sense the correlation between adding throttle, how much, and how it relates to the exit. It's very interesting. The speeds at Turn 10 are insane, especially for the LMP2 and LMP3 cars.

I noticed that the LMP2 and LMP3 cars stay off the curbs on the second, third, and fourth parts of the bus stop. They make an effort to run around them or only use the very low part of the curb. The GTD cars try to cut through those curbs. Watching for a while, you can see that this is not random.

At Turn 10 on the exit, the LMP2 and LMP3 cars rarely drive over the curb, while the Supertrofeo and GTD cars ride on top of the curb and often go over it with all four wheels.

It could be due to different regulations.

In other news, the week for my engine installation has finally arrived, and work will begin on Monday, June 26th. The hope is that by the end of the week, a reliable estimate for completion time can be determined, and I can start planning the rest of the 2023 season.
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[rhyary]

Hint…..
If you know, you know

[e92BMW///M3]

Good luck with the engine install this week. I am sure the team at ACM will do a great job.

I was trying to piece together your rear rim fitment between this thread and your FI-R for sale thread and saw maybe you've run 19x10.5 +23 and mounted a 305/30/19... did you have any rubbing with that setup and/or need anything special to get it to fit? I've heard some fitments rubbing the fuel neck, etc. but didn't seem to come across much rubbing issues mentioned in your thread. Thanks!

[rhyary]

My target offset is 22 all around.

I run the FI-R with 12mm or 10mm spacer depending on the tire.

The 305/30/19 I run with 12mm and the 275/35/19 with 10mm.

Both clear the fender and I have no rubbing in or out.

The FI are 23 offset in the rear and I run it as is.

[rhyary]

because pretty.

[rhyary]

Because I am starting to see the light at the end of the dark dark tunnel

[nsogiba]

Glad you enjoyed the IMSA race. I attended for the first time in 2021 and loved the experience, but couldn't make it the last few years due to family obligations. If you're ever at the Glen I'd like to catch up. Are you attending the GVC HPDE event there on 8/4-8/6? Car gonna be done in time? Doesn't look like you have much left.

[rhyary]

Originally Posted by nsogiba

Glad you enjoyed the IMSA race. I attended for the first time in 2021 and loved the experience, but couldn't make it the last few years due to family obligations. If you're ever at the Glen I'd like to catch up. Are you attending the GVC HPDE event there on 8/4-8/6? Car gonna be done in time? Doesn't look like you have much left.

I can’t make it on 8/4-8/6 because of work obligation. I was signed up as instructor and was planning to attend anyway, but had to cancel.

I am at the Glen with SCDA 8/28-8/29, with GVC 9/29-10/01 and with MassTuning 10/20-10/22 Hopefully with my car.

[nsogiba]

Awesome. See you at the 9/29 event.

[rhyary]

Picture of something I can recognize.

Carbahn requested that lots of oil components will not be transfered from the old engine.

So many new gaskets, clamps, oil seals, selonoids will be new.

Really trying to prevent a stupid little cheap part derailing the rest of the season.

Also, anything that is in the back of the engine, close to the firewall and hard to get, will be given a priority to replace with new.

This is a tricky situation, there are thousands of dollars that can be added to the project because we already there or it is easy to replace because the motor is out. But it just get to be unreasnoble at some point.

To begin with, many would not go this route to begin with, and I totally understand that. If I was itching to get into something else, this would be the time to do it.

But, as it stands, I am just itching to get back to driving my car

[rhyary]

Was told the engine was running and most of the car put together but the Voltfreak battery died. Now waiting for Anti Gravity to come in.

Then the resurrection can continue.

[rhyary]

Anti Gravity showed up last Friday.

Car went through 2 test drives of 5 miles each.
No codes, No leaks, shifts well.

It is a good time to explain the DCT situation.
My DCT had the Slone goodies and the SSP Spec-R clutches. Loved it.

But the main output shaft bearing died last summer. I literarly just bought a used DCT with 35k in supposetly an excelent shape. The issue it had, the seller said, turned out to be a harness on the car side. But we could not take the chance mid season last year.

So Autocouture installed a DCT from a crashed car with 125k miles they had in the shop, as is to get the season over. The idea was to move my goodies to the 35k miles transmission.

The high mileage transmission worked, but compare to my SSP Spec-R clutches and slone deep oil pan, it wasn’t satisfying.

Then the engine died.

So while waiting to the Carbahn engine, the low milage DCT was prepped with all the goodies from my original DCT and was installed together with engine.

The fact that we are getting good shifts, no codes and no leaks is a good sign that the low mileage but unknown DCT is in good shape.

Next week I hope Autocouture will be doing a much more rigourus test. The next hurdle is to pass NYS inspection. I drive this car to the track.

We need to get to 200 miles than change oil.

Anyone volunteers to drive 200 miles in NJ traffic?

[rhyary]

How Does ABS Work?

The ABS logic in a stock car resides between the driver and the contact patch. I actually prepared a presentation on this topic. Therefore, efficient braking is not pressing as hard as possible on the brake pedal, but rather understanding the limits of your specific ABS system and how it interacts with your suspension and tire selection.

For me, given my tire experiments the best pressure is between 900 and 1100 psi. That means geting deeper and pressing harder on the brakes will not yield the best lap time.

For those on the perfect tires selection on 18” wheels, what is your best pedal pressure?

Here is a video demonstrating the ABS computer and its operation."

https://youtu.be/IKi5O3ZlSu4

[MaX PL]

My only experience with no ABS has been with video games many years ago and if that is representative of what's capable with our ABS cars, but with correct pedal application, than me and/or us are definitely far off from proper braking.

Last year I had a magical day of braking into T1 at Lime Rock, where it felt like I was applying less brake pedal pressure, yet braking as well if not better than going pedal to the floor.
I will practice this there again next time out before replicating it at other turns and other tracks.

I think a big issue with braking is what I hear communicated from "instructors". Instructors in parentheses as I don't feel many of them know very much.
Most if not all say full pedal when beginning to brake into a turn, when, compared to no ABS video game braking, it's mostly a light to progressively light application to where the car ends up taking less distance to brake when done correctly.

Am I correct in assuming this can be replicated with an ABS car if done correctly?

[rhyary]

My experience with no ABS was when my speed sensore failed. Unfortunetly, when this happens, I also lost all CAN bus information about me braking without ABS.

One way to analyse the effectivnes of braking is to compare deceleration G forces while looking at brake pressure.

It is no perfect, but gives a clue to what is happening. A unique capability of the E92 M3 CAN bus is that you get 5 PSI data points. The pedal and the four wheels. So you can see how much pressur you apply, and how much pressure the wheels get. From the video above, it is clear to see why if I press 2000psi I only get 100psi in the rear. So if that is the case, the rears are in the air and not helping at all in the braking.

I have a slide that shows how when the ABS is applying more pressure in the rear, the front actually gets less pressure but the LongAcc shows more decelarstion.

[rhyary]

The goal this week is to pickup the car Friday Aug 25th, drive to WGI Sunday and two track days at WGI Mon - Tue.

So what has to be done this week.
Mon - car went for a long easy test drive. Everything is good but oil temp. On easy drive the oil temp was higher than it should

Tue (today) - review oil temp situation and remedy

Wed - Assume oil temp remedy - another test drive and if stable - go on boost.

Thu - I want to go down to ACM and drive the car to assess how the complete package feels. I have 5 years doing track days in this car that I can feel things ACM can’t.

Friday - bribing my wife to give me a ride to ACM to pickup

Sat - test drive on local roads

Everyday, something can come up that derail the plans. Next test will be LRP on Sep 11th.

It really is a situation that until I get to a track and do a full send, I don’t know what I will be facing. I totally understand drivers who chose to buy a new car, do minimum modificstion and drive.

[rhyary]

It is alive

[rhyary]

Drove my car today for 170 miles to break-in the engine. All is well. Tomorrow morning oil change and I bring it home. I have not driven it since Oct 2022 and it sure nice to be in an E92 M3.

And I got to say proper goodbye to my piston.

[rhyary]

My car is back.
First day at WGI went well.
First session up to 7000 rpm
Second session up to 7500 rpm
Third session up to 8000 rpm
Last session full send not watching RPM.

I had to deal with the DCT.
The DCT had no issues in general and shifting was as expected. Except…

If I was on full throttle going thru the esses on either 5th or 6th the transmission went into “gear selection” message and I was either on the odd gears or even gears until I shut off the engine and restart. Any restard returned everything to normal operstion.

First mitigation was to get to full throttle after T-1 and shif normal 4-5 until I get to the bottom of T-3 (passed T-2) then keep full throttle and short shift to 7th gear. That got me to 112mph and 7th was able to maintain that speed all thru the esses and accelerated on the straight into the bus stop. This strategy worked fine and no DCT issues.

The problem with that approach was that once I passed the max uphill slope, I did not want to risk it by shiting down to 6th.

So then I tried a different strategy:
After T-1 I went full trottle 4-5 than just before the most steepest part into T-3 I shifted to 6th and kept it at 7000 rpm. That eliminated any DCT issue and allowed me to go to full throttle as soon as the slope moderated (top of T-3) and continue to shift to 7th at 8000 or higher.

Second day started great and normal. Third session I blew the coolant hose in the back of the engine on the straight and lost all the coolant. At 120mph all the cooland was going straight in the air and not on the tires. Took T-1 normal and continued right side of the track with the intention of driving to the escape road. Alas, as soon as I slowed down and headed over to pit lane, the cooland got on the rear tires and I had do some majore hands work to keep the car from going to the wall. Saved it and drove to the garages.

Got a friend (you need to have friends) to trailer to Autocouture. Dropped the car off and drive back to WGI to pickup his Porsche. We the drove all night east. It was fun loading up his Porsche in the middle of the night in torrential rain. But we did it.

ACM already diagnosed the car and said the hose in the back of the engine split in three places. It should be fixed and ready next week for Sep 11th LRP day.

Good news, I did not hit the wall. Engine is great. Oil temp was steady at 270 and car is totally normal driving around the garages amd on and off the trailer.

Bad news, there are none. This is the sport.

Results at full send: 2:09 on old tires from last year. So will be back to last year pace of 2:06 when we figure out the DCT and newer tires. Then it is after SYT_Shadow 2:02 times :-)

[rhyary]

In all its glory