Cars VRC Prototype Series

[Dirk Steffen]

To get you in the right mood ;-)

 

[SunBro]

Thanks for the responses.
I am well aware of your points although I disagree about not being able to compare this Bentley Speed 8 with other Le Mans prototypes. Of course you can compare them.

In terms of drive-ability and a general setup for the only tracks this car raced at one would assume from the comments of the drivers of the 2003 car that the car was very stable and easy to drive compared to the 2001 + 2002 design (which suffered from an aero imbalance as of a non ideal airflow to the rear wing which was cured with the complete redesign for the 2003 season), certainly not nervous in any way.

I have put in now many hours of testing and also had a good look at plenty of the data and have made some observations.

With some work with the setup one can get the car relatively stable at Le Mans. It is still not unproblematic, especially over bumps while turning but I am going to work on that further.
It would have been nice if such a default setup would be shipped with the car.

The aero data is downright FANTASTIC! Great job on matching the available data with the actual performance of the car in terms of downforce, drag figures vs. what is known on the web. I found the data on aero testing with a low downforce configuration to be consistently within +/- 10% of available data which is indeed a very tight match ;-) ... love it!
This is just a single example at 150mph (be aware that these math channels are not completely filtered of longitudinal forces, hence the F/R ratio is dirty but the overall DF figures are very close to actual figures (see AIM data trace):
View attachment 305626
AIM data from telemetry dump:
View attachment 305627

The suspension geometry is very neat, dynamic toe and camber looks absolutely realistic to what one would assume such a car would perform like (It would be great if you could share a bit more on your approach here - did you have actual data for this, did you build from assumptions, etc ...).

Nicely sorted dynamic toe and camber:
View attachment 305628

I would love to have some input on lap time performance of this car.
I am nowhere near able to get even in the ballpark of the actual cars lap times during the 2003 Le Mans sessions.
My fastest times (without traffic) on medium tires and starting with a 45 liter fuel load are in the low 3:43:xxx (the AI on 100% is running about a second slower per lap) on the "sx_lemans" v0.9.2 track (which currently has the most realistic layout available to Assetto Corsa.
I am aware that between 2003 and the data this track is based on has been some modification to the Tetre Rouge section but these do not result in a 10 sec + difference per lap.

Here is some general info on track changes over the years:
https://www.maisonblanche.co.uk/circuits.html
View attachment 305630

What are other people performing like?

I have attached my setup I used to this post - I am curious, please share!

Btw, I love the looks of the car and the sounds (especially the external are absolutely magnificent!

View attachment 305632

Nice!

Tiny little something to note maybe; i keep seeing posts about how the le-mans we have is very inaccurate and it's about 10 seconds longer than the real thing.

 

[garyjpaterson]

Tiny little something to note maybe; i keep seeing posts about how the le-mans we have is very inaccurate and it's about 10 seconds longer than the real thing.

He mentioned "sx_lemans" which is not the hideously inaccurate mod thats been around for years, its in fact a Forza rip which is far, far more accurate, but of course has its own flaws too (no physics mesh, so its unrealistically bumpy, track origin strangely not centred so a large portion of the lap is heavily affected by the floating point thing, and of course just the general terrible optimisation that inherently comes from Forza based tracks).
Not to mention it just looks really bad IMO, as all Forza tracks outside of its native engine seem to do.

 

[SunBro]

He mentioned "sx_lemans" which is not the hideously inaccurate mod thats been around for years, its in fact a Forza rip which is far, far more accurate, but of course has its own flaws too (no physics mesh, so its unrealistically bumpy, track origin strangely not centred so a large portion of the lap is heavily affected by the floating point thing, and of course just the general terrible optimisation that inherently comes from Forza based tracks).
Not to mention it just looks really bad IMO, as all Forza tracks outside of its native engine seem to do.

Oh didn't notice that. My bad.

 

[Qazdar Karim]

Thanks for the responses.
I am well aware of your points although I disagree about not being able to compare this Bentley Speed 8 with other Le Mans prototypes. Of course you can compare them.

In terms of drive-ability and a general setup for the only tracks this car raced at one would assume from the comments of the drivers of the 2003 car that the car was very stable and easy to drive compared to the 2001 + 2002 design (which suffered from an aero imbalance as of a non ideal airflow to the rear wing which was cured with the complete redesign for the 2003 season), certainly not nervous in any way.

I have put in now many hours of testing and also had a good look at plenty of the data and have made some observations.

With some work with the setup one can get the car relatively stable at Le Mans. It is still not unproblematic, especially over bumps while turning but I am going to work on that further.
It would have been nice if such a default setup would be shipped with the car.

The aero data is downright FANTASTIC! Great job on matching the available data with the actual performance of the car in terms of downforce, drag figures vs. what is known on the web. I found the data on aero testing with a low downforce configuration to be consistently within +/- 10% of available data which is indeed a very tight match ;-) ... love it!
This is just a single example at 150mph (be aware that these math channels are not completely filtered of longitudinal forces, hence the F/R ratio is dirty but the overall DF figures are very close to actual figures (see AIM data trace):
View attachment 305626
AIM data from telemetry dump:
View attachment 305627

The suspension geometry is very neat, dynamic toe and camber looks absolutely realistic to what one would assume such a car would perform like (It would be great if you could share a bit more on your approach here - did you have actual data for this, did you build from assumptions, etc ...).

Nicely sorted dynamic toe and camber:
View attachment 305628

I would love to have some input on lap time performance of this car.
I am nowhere near able to get even in the ballpark of the actual cars lap times during the 2003 Le Mans sessions.
My fastest times (without traffic) on medium tires and starting with a 45 liter fuel load are in the low 3:43:xxx (the AI on 100% is running about a second slower per lap) on the "sx_lemans" v0.9.2 track (which currently has the most realistic layout available to Assetto Corsa.
I am aware that between 2003 and the data this track is based on has been some modification to the Tetre Rouge section but these do not result in a 10 sec + difference per lap.

Here is some general info on track changes over the years:
https://www.maisonblanche.co.uk/circuits.html
View attachment 305630

What are other people performing like?

I have attached my setup I used to this post - I am curious, please share!

Btw, I love the looks of the car and the sounds (especially the external are absolutely magnificent!

View attachment 305632

Nice!

- You will start losing downforce under 5/20 mm ride heights (f/r), keep an eye on that when you're making a setup.
- It's very complicated to explain my method of cooking suspension geometries. This one has reasonably low camber gains on both the front and the rear (with a bit more on the rear). I also always aim for a very low bump steer, I couldn't get it to where I want on this car on the rear without straying away from what I saw on some images (attach points, arms arrangements etc).
- As I said before, you need long gears for this car: there are sources that stipulate 158kph for the 1st gear in a lemans configuration. Maximum torque is reached quite early in the rpm range.

 

[Dirk Steffen]

- You will start losing downforce under 5/20 mm ride heights (f/r), keep an eye on that when you're making a setup.
- It's very complicated to explain my method of cooking suspension geometries. This one has reasonably low camber gains on both the front and the rear (with a bit more on the rear). I also always aim for a very low bump steer, I couldn't get it to where I want on this car on the rear without straying away from what I saw on some images (attach points, arms arrangements etc).
- As I said before, you need long gears for this car: there are sources that stipulate 158kph for the 1st gear in a lemans configuration. Maximum torque is reached quite early in the rpm range.

Yep, I was surprised when I saw the aero maps (scatter plot in AIM) and saw teh very low front end of the car.
It all made sense though when reading on the comments (I think an interview of Peter Elleray) how they redeveloped the front suspension design to control the porpoising and aero instability the 2001 / 2002 car had tendencies to.

Here is a tip for people who use Motec i2 Pro to keep tabs on your ride height and optimal aero - set yourself boundary marks in your ride height channels - it makes visualizing and analysing data so much faster:

The tip on the long first gear is gold!
Changing driving habits from trying to get out of tight turns in second gear with a regular, even gearing to using a very long first gear to overcome that monstrous torque immediately shaved off 0.5 second and makes the car so much easier to drive out of Mullsannes Corner and Arnage.

What really helped me though to shave off more time was a little more work on ride height, springs and dampers and fine tuning the LSD some more.

I am now down to mid 03:40:xxx times and still have 5 seconds to go ( I am curious though how much time the changed Tetre Rouge section and the overly bumpy Esses section in this Circuit de la Sarthe version actually cost.

Here is the latest setup:
https://acstuff.ru/s/YGCu

It is still early days with the suspension and damper, I will have to do more there but I am slowly getting it more driveable.

 

[MHS]

Bradley Project 8 has just been updated to V1.1, addressing some of the issues that were reported since last week release. As ussual you can download the new version using your purchase credentials.
Full changelog can be seen at our website.

Today we are also inaugurating our brand new and much asked mailing system. From now on, you will receive an email notification advicing a mod you have purchased was updated or that a new mod has been released. As this is the first time we send this quantity of emails, please check that the email might have been interpreted as spam, so be sure to set it as "not spam".

 

[AccAkut]

Bradley Project 8 has just been updated to V1.1, addressing some of the issues that were reported since last week release. As ussual you can download the new version using your purchase credentials.
Full changelog can be seen at our website.

Today we are also inaugurating our brand new and much asked mailing system. From now on, you will receive an email notification advicing a mod you have purchased was updated or that a new mod has been released. As this is the first time we send this quantity of emails, please check that the email might have been interpreted as spam, so be sure to set it as "not spam".

you should add a link to your site to the emails

 

[MHS]

Quick update on the Pan...

 

[386]

the sx track has been getting constant updates over the pass few days, you should try it out again its quite better

 

[garyjpaterson]

the sx track has been getting constant updates over the pass few days, you should try it out again its quite better

Its still pretty crazy bumpy in sector 1...

 

[386]

Still better than the RD one, hopefully it can become a solid track at some point. Or even better a scratch made LIDAR Le Mans

 

[German-Race-Fanatic1999]

Where I can get that sx_le_mans mod?. And is there any chance,(after finishing your Audi and Panoz), for some French or Japanese beauty´s like the Courage C60 and the Dome S101

Courage C60:

Dome S101:

 

[GTAce]

Once these cars are out, we finally need a proper, scratch-made Le Mans and rolling starts.

 

[MHS]

 

[Ryno917]

It's amazing how utterly tired and basic that car looks after the hot mess that is current LMP1.

Great work, though! Looking forward to the big green one having a playmate!

 

[MHS]

 

[Terry Rock]

Great job on that Bradley Project-8.
I absolutely love that car.
Took it out and did some low-speed, wet testing at Monza the other night. It felt really good.
Love the exhaust note as well.
Thanks.

 

[386]

are you guys thinking about doing a certain German V12 prototype after this one?

 

[SunBro]

are you guys thinking about doing a certain German V12 prototype after this one?

That's been asked a lot of times by a lot of people(including me)

They'll wait and see after these cars are done.