HPDE experiments, results and observations

[tsk94]

Where are the latest experiments, results, and observations??

[DRLane]

Originally Posted by tsk94

Where are the latest experiments, results, and observations??

Still cold in the NE. You watching the news man?

[tsk94]

Originally Posted by DRLane

Still cold in the NE. You watching the news man?

No
Sometimes I forget everyone here is not in CA/TX and able to track year around lol. I still got a solid 3 months before track season starts up here...

[DRLane]

Originally Posted by tsk94

No
Sometimes I forget everyone here is not in CA/TX and able to track year around lol. I still got a solid 3 months before track season starts up here...

Generally the Texas folk lead with their location…

Yes, I’m patiently waiting here in CO. Been an unusually cold winter on the front range. But also at this rate my car is probably a couple months out for being driveable.

[rhyary]

I am not even in the North East this month.

[razorlab]

Originally Posted by rhyary

The Red Supra with the Aero?
I could not keep up with it.

Looking forward to seeing you

Yup, that's the one. I'll also have aero this season.

[sbo76]

Originally Posted by DRLane

Generally the Texas folk lead with their location…

Yes, I’m patiently waiting here in CO. Been an unusually cold winter on the front range. But also at this rate my car is probably a couple months out for being driveable.

I am sorry. It has been cold her in CA but i have already gotten in four track days this year. If it makes you feel better we are all charged a premium through our property and state tax for the ability to race year round

[rhyary]

Oh that sounds, that sound.
when will it be spring again.

https://youtu.be/KOx30k4ktns

[rhyary]

Listen how he shuts off the throttle and WAIT to pickup the throttle ONLY once he passed the apex. He has so much entry speed, he does not need to add throttle.

Also, not matter how short the distance between turns, he adds throttle, then shuts if off.

The times he adds throttle at or before the apex is on corners he WANTS to understeer to the outside because the next corner is a shallow one and he can use a shallow steering angle. So rather than opening the steering, he keeps the steering angle and go wide using the throttle.

Focus by listening to the engine and where he is on the track. Look a head. don’t look at the car.

https://youtu.be/Q0FmiydKmPQ

[rhyary]

Time for a 2023 update
So last October I did my best time at WGI at the 10am session:
https://youtu.be/nMLN8iDA_v8
.
Then at the 1pm I blew the engine up. There was no drama, there were no leaks. Code came up which turns up to be a Coil #1. I limped into the garage, loaded up my car and started my drive home with a motor that sounded like missing a cylinder. 12 miles out of Watkins Glen the engine died, luckily at an intersection with a gas station that has good coffee. I stopped there before. Took it straight to Autocouture in NJ.

I had to do serious thinking. What do I want to do. No matter what, it will be expensive.

During my coaching I get to ride (and drive) other cars. This monday I drove 2 of my students cars, an F80 M3 and Porsche Cayman Cup Car. The F80M3 is so fast, so much power, but I felt nothing. Fast is not the only thing I want. I want an experience. Engagement. The Cayman Cup car, a true race car, felt great, amazing, loved that, but not more than my E92 M3.

I decided I don’t want to deal with another used engine. I also decided to keep the supercharger for a very practicle reason. At track days, if you don’t have a decent speeds on the straights, you constantly get passed on the straights, only to catch up to most cars in the turns and consequently you lap is mostly spent behind slow cars. So with so many modern cars being so fast on the straight, I wanted to keep the car the same. But not exactly the same.

This brings me to the Carbahn Engine options.
A stroker was out of the question. I don’t have the budget for engine rebuilds it requires with 30 trackdays a year.

Next was the 4.1L designed for the supercharger. Carbahn was asked to build it for reliability, not for power. A oil baffle option was added and the compression option was selected to be as close to stock as possible.

The tune from ESS may not be ideal, so tuning is something to tackle. The main challange was to find a good block, without spending the money on good used engine. The first block ACM sent to Carbhan was not good. A second block was sent and deemed to be good.

Now all that is left to do is wait for the build, hopefull days not weeks, and then assemble the car together.

This expense necessitated delaying proactive work that will have to be pushed to next year. At the same time all fluids were replaced, the supercharger is being rebuilt with new gaskets, new gears and new oil drain tube. 72k miles, mostly trackdays, take a toll on everything.

This is expensive, but I can’t complain too much. I have been doing trackdays ever since I bought the car with 6k miles. Nothing last forever, not even a 2013 E92 M3 S65 with ss slapped on it at 8k miles.

[rhyary]

The Engine Specs

The CarBahn Autoworks S65 4.1L bored engine is built features high performance over-sized forged pistons, a forged crankshaft with stock stroke, and high-strength forged Carrillo connecting rods. The bore is increased to 92.5 mm. Rebuild improves durability with Clevite-CarBahn racing rod bearings, CarBahn Autoworks valve springs, an MLS (Multi-Layer Steel) head gasket, a valve job with new hydraulic lifters, plus timing chains, timing chain guides, timing chain tensioners and all associated seals and gaskets.

[MaX PL]

rhyary, you've been so quiet all winter. I figured something was up.

[admranger]

sorry for the loss of your engine. I think you're making a reasonable choice given what you want out of the car. GL GL with the rebuild, etc. New personal best await.

Me? I'd have gone with different sized pistons all around, and then randomly change them to see what happens.

Sorry, just trying to make light of a difficult situation.

[rhyary]

Still waiting for my engine.
last I heard it is being built and shipping back to Autocouture next week. There is still a long road ahead even after it shipped east.

In the mean time I continue to coach and have friends or students that let me drive their car in the instructor group.

This Friday I drove again the Porsche Cyaman cup car and this time it was a dry day at LRP. I really enjoyed that car. I also drove a street legal but track prepared E46 M3. I did not get too comfortable with it. I need more seat time.

Lastly I drove a stock Mustang GT. I keep being surprised at the power these type of cars make at a lower RPM and the big tires, even MP4S have so much traction using a soft OEM suspension. If you, gentely, put it on its side then add steering slowly, it leans and leans and leans until enough of the inside rear is in the air to start an oversteer motion (T3 at LRP) Having said that, any side to side not pleasant with “who knows what bouncing on the springs” will do.

Trying to stay positive and driving anything I can find while “patiently” waiting for my car.

It will definetly be interesting to drive a stock E92 M3 to see where I started. I coached few stock E92M3 but have not driven one.

[rhyary]

Some good news, I suppose. Had a good conversation with Carbahn and they provided a reasonable ETA. It looks like Autocouture will have the engine and start installing it on June 5th. After that, it will be anyone's guess if it will all come together. I don't think it will be as simple as getting the engine, installing it, and off to the races.

The Carbahn motor for the supercharger is designed with a bit less compression. So the plan is to run a small pulley on the ESS supercharger to achieve the same or roughly the same performance.

If I understand correctly, a smaller pulley will have a greater effect at lower RPMs, and the Carbahn components are strong enough to handle the increased boost at higher RPMs.

Of course, having enough fuel to add power is also crucial, so we'll see. At the moment, I plan to run it with the ESS software.

Changing the subject, my wish came true. This Sunday at PMP, I drove a stock E92 M3 for one session. While I enjoyed it, I can't believe how softly tuned a stock M3 is. I suppose that's what makes it a comfortable street car with a racing engine.

My student for the day had a track-prepped E92 M3 with RE-71RS tires. I really enjoyed that car and drove it a few times in different sessions. However, I didn't like the 285/30/18 tire size. I think the "standard" 275/35/18 would have been better. The car has 10" wide wheels.

Anyway, the weather was good. I missed my car, but I got to drive two flavors of the E92 M3 and enjoyed the day.

[leftfootbr8king]

Driving on a matching set of tires was probably a different experience for you as well…

[rhyary]

Originally Posted by leftfootbr8king

Driving on a matching set of tires was probably a different experience for you as well…

made no difference.
I drive the traction I have.

I did like the RE-71RS.

[redpriest]

Originally Posted by rhyary

This brings me to the Carbahn Engine options.
A stroker was out of the question. I don’t have the budget for engine rebuilds it requires with 30 trackdays a year.

Hold on professor, where did you hear engine rebuild requirements? Carbahn would not disclose this to me.

[redpriest]

Originally Posted by rhyary

Some good news, I suppose. Had a good conversation with Carbahn and they provided a reasonable ETA. It looks like Autocouture will have the engine and start installing it on June 5th. After that, it will be anyone's guess if it will all come together. I don't think it will be as simple as getting the engine, installing it, and off to the races.

My reasonable ETA moved every 2 weeks for months, just FYI. I like the engine but if you aren't their race team you are priority zero.

[rhyary]

Originally Posted by redpriest

Hold on professor, where did you hear engine rebuild requirements? Carbahn would not disclose this to me.

I did not mean to imply that I know their requirements. I meant to say that with me doing 30 track days a year, a stroker was not in my budget.

[dvas]

Originally Posted by rhyary

One day on MPSS at NYST.
luckily I did not pay full price but still.

this is on 1:38 pace with one lap 1:37.8

I assume this pic was taken after your last session of the day? What did these tires look like just prior to the last session? I can't imagine they went from looking ok and trackable to this in a single session.

[rhyary]

Good news! The engine arrived at Autocouture from Carbahn. Now we need to schedule the installation, and who knows what challenges ACM will face? It feels like receiving the engine is just the beginning, not the end.

In the meantime, I attended a track day at Thompson Speedway Motorsport Park (TSMP). TSMP may not have the best surface, but I had a lot of fun.

I had the opportunity to drive three students' cars: the BMW M2, Honda S2000, and the Porsche Cayman. Besides my own car, I still prefer the mid-engine Cayman the most.

Since it was my first time at TSMP, my goal was to reach top speed as quickly as possible. I studied a few YouTube videos and settled on three clips. Two of them provided a turn-by-turn guide, while the third featured a GT3 Cup car completing a very fast lap in 1:11.

I used the GT3's fast lap as a reference to analyze minimum speeds, turn-ins, and when the driver applied throttle on exit. I paused the video multiple times to understand the relationship between the 1:11 lap and the instructions given in the turn-by-turn clips.

Here are the three main videos I used to study TSMP:

https://youtu.be/r96kzgEbDao
.
https://youtu.be/Gt7ipI9v_wE
.
https://youtu.be/civ2Ov3PTG4