Cars Ford Spec Racer for Assetto Corsa 2.1

[Gevatter]

@Daniel Jimenez
Just a few words from me as somebody who has no idea about physics modding. It took me about half a lap around Laguna Seca to get the feeling that something about how the car drives is wrong. The tires lock on downshifts no matter how much I rev the engine, it has next to no rear end grip and I spun it three times on my warmup lap. Warming up the tires didn't help, so I came here to whine about it My suspicions that something is amiss in the physics was confirmed. You can see it in this thread.

The model is very well done. Like with the Skippy, you did a very good job with it. I like the texture work and the skins that come with it. But the physics are just not realistic, and the car doesn't handle anything like it should, judging by on board videos. I also don't think there was any ill intent or malice behind anything, just a bad physics modder.

In the end, Simracing, as the name implies, is about simulating the real world as well as possible, and that is what I personally am after. I like to drive cars and immerse myself in their little quirks. The thing for me is, if it's not done either properly or at least believably, what is the point of even having it? Why would I want to drive a car that looks like a SRF but handles nothing like it? I hope somebody could make better physics for that car one day, because it would be a shame to let your hard work on the model go to waste.

(Yes I'm moaning because I'm disappointed, because I was looking forward to this very much, but of course I'm not begrudging anybody their enjoyment of this car.)

 

[Luis Mercury]

Kunos recommends taking Formula K as a base.

out of respect for other people's work, with Daniel we have decided to take his last work as a basis.
Which? His skippy! (physics by Kyuubeey)

Kyuubeey had already reported that he could not get involved in the project due to time constraints.

so ...... Is it necessary to reinvent the wheel? SRF is basically a formula.
suspension and type of tires are largely coincident.

We shared long hours with Daniel on Discord and Whatsapp.
It was very fun hours ... a great hobby certainly.

Circumstance where we have learned a lot.
At one point, we had to make a decision.

replicate GEN2 or replicate GEN3 (to be or not to be)

If we made the GEN3 ... the real data would take us away from an inevitable comparison ... ... the GEN2 of iRacing.
I insist ...
If we made the GEN3 ... the real data would take us away from an inevitable comparison ... ... the GEN2 of iRacing.

And as our experience is limited to a humble learning curve ... we decided to move forward with GEN2
and leaving GEN3 and its current data for the second stage of development and more learning.

We have no idea what the data with which iRacing has worked. Our physical interpretations aren't an absolute fantasy.
however ... it has a lot of data entered into physics that we have collected from good sources

This is a physics only version of my interpretation of the Spec Ford where I have enjoyed for many years in iRacing.
This is not meant to be a 100% accurate representation of the car as no real data or telemetry is available (on which iR worked) and I doubt it ever will be."

so ... I can say that SFR GEN2 should be as fun as the SRF unavoidable reference of iRacing.

and this is not all ... there is the beautiful challenge of recreating GEN3 where we find many friends totally motivated.

Like every magician, I apologize for having assumed the role of .....

I'm convinced that the GEN2 and GEN3 versions can live together fraternally

in short ... the beneficiaries are all (We are learning and you are enjoying)

https://assettocorsamods.net/threads/your-first-car-in-assetto-corsa-basic-guide.1019/

 

[Daniel Jimenez]

So, the skippy was not like iRacing one and people complains.
The Spec racer is closer to the iRacing one and people still complains.
Then I said that physics would be improved so everyone could be happy, but no, some ones still complains... ¿what else do you want lol? ¿for me to buy and send you a real SRF at each one of your homes? I'm sure some people still would complain about that... Jesus I even try to calm down things and be chill and nice, but the answer was to accusing me of "trying to hide something", are you for real? damn.

 

[LilSki]

The point here is the SRF shares nothing with a skippy IRL. No parts are shared and the geometries are completely different. There is so much data out there for this car I doubt it would be very hard to put a proper suspension under it instead of just copying from the skippy.

And also trying to base a car on another sim is just bad practice IMO. You should always try to base a car against real data. Again there is a good amount of data out there for this car.

And also the only difference between a GEN2 and GEN3 is the engine from what I can find. The engine to my knowledge has not been the topic of debate here. It's the suspension. So using data from the GEN3 would be perfectly fine except for the engine.

 

[Kyuubeey]

Hello Luis,

You're very incorrect about there being no data. This is one of the cars where such a claim is bordering on ridiculous.

Collaborating with some people we managed to find all of the suspension kinematics including roll curves, roll centers, center of gravity height estimates and so on. We found damper dyno graphs for I believe newer Penske dampers. We found engine dynos. We found detailed dimensions, alignment, default setups. Spring poundage and I believe even motion ratios. Data about damper and spring stroke. The list goes on.

There's generally more data than what I've had for some of my roadcar mods. I'm not surprised if we could manage to find some rudimentary aerodynamics and perhaps even tire testing as well. In addition there's a lot of clear and high quality suspension images. Not surprised if CAD, laserscans or schematics also show up.

It's okay to admit that you don't know what you're doing at a high level and you did your best to help. No one is going to ridicule you. If you tried to make for example a suspension geometry and found data and tried your best to implement it, I would have been happy to see someone new entering the physics dev world.

I will however ridicule you for attempting to appear as someone who knows what they're talking about and misleading the general public about the context surrounding the car.

Daniel, not everyone is fully aware of the context and history of the project (Even I was not and it seems you yourself were not ). I hope you can forgive them.

 

[Luis Mercury]

I have a lot to learn from you.
and I only learn by doing.

I pass my data to you privately.

 

[Kyuubeey]

I have a lot to learn from you.
and I only learn by doing.

I pass my data to you privately.

Hey,

My advice is to read some racecar engineering books first. Get a basic understanding of the concepts in a racing context. After that it would be very good to read some real mechanics books.

I don't know how beginner friendly it is, but

is a book I remember as having more than what you need for making sim cars.

The rest is a lot of research and study of manuals, tests, everything to do with real cars, and of course learning the simulation engine and simulation in general. We can help you with those to an extent, just ask.

 

[Luis Mercury]

My problem is to collect information .... then is a copy and paste in suspension.ini

Can you help?

 

[Kyuubeey]

Can you help?

You can ask and if it won't take me too long and I can advise you, I will help. If I can't, perhaps I will direct you to someone who can.

For acquiring the book, I cannot. It would be respectful to just buy it, but, well, you know, there are other avenues for the sake of study.

 

[Luis Mercury]

OK
we go in parts .....

[BASIC]
WHEELBASE = ???? (2,337) source https://en.wikipedia.org/wiki/Spec_Racer_Ford
CG_LOCATION = ????? (0.46) source ????

[ARB]
FRONT = ????? (35000) source ????
REAR = ?????? (38000) source ???

 

[Kyuubeey]

That's not how it works. It's your job to first learn how to search for information or determine it yourself, and then how to interpret that information.

Wheelbase and if you're lucky CoG are often reported. CoG is for sprung mass only, not unsprung. Check ingame wheel loading.

Rollbars must be either found as data, determined or guessed.

Here's a nice calculator if you have dimensions but didn't measure force yourself and still want a good result.

https://balancemotorsport.co.uk/suspension/anti-roll-bars

This just gives you the bar rate, you need to figure out the wheelrate yourself. Search online how to first before you ask others.

 

[Luis Mercury]

well ... there we go

WHEELBASE = 2,337 source https://en.wikipedia.org/wiki/Spec_Racer_Ford

You're in agreement?

this way we are going beyond point to point.

 

[Luis Mercury]

Do you agree?

WHEELBASE = 2,337 source https://en.wikipedia.org/wiki/Spec_Racer_Ford
Wheelbase distance in meters

Or is there another piece of information to consider? Which? And how would you do it?

 

[Luis Mercury]

The SRF3 and SRF currently run as two separate National classes until the end of 2017, when the SRF will be designated as a Regional class only.
http://www.hrace.com/srf.html
CG_LOCATION = ????? (0.46) source ????

Does anyone know the weight distribution of GEN3?

 

[Kyuubeey]

You find multiple sources. All you can. Because wheelbase, track etc. will/can change (even if only 0.1mm) if you change the car height, camber, wheel offset etc. you need multiple sources. Often these are not actually true; the wheelbase could be for example 2.3373m in reality. But it's close enough.

Anyway, let's not spam the thread.

 

[Luis Mercury]

Cg_Location....only Front Weight distribution in percentage

two smart people don't spam ... debated and grow in knowledge.

we will not discuss suspension.ini in one day but if I want to discuss a week for each line

 

[Luis Mercury]

with total humility and in order to recognize my conceptual errors .... Do you agree with this value?
Wheelbase distance in meters 2.337 for WHEELBASE?
and in case of disagreement ..... concretely and objectively .... why?
It has your data for WHEELBASE?

 

[Luis Mercury]

Don't worry Kyuubeey. You have great knowledge, but I will move publicly with the physics of GEN3.

For 2 reasons ..... I need to be corrected and detect the error of my concept.
We must all participate and it has to be an open project.

In this way we will minimize errors ... we will focus our efforts and we will all gain knowledge.

 

[Kyuubeey]

My opinion is largely irrelevant. I am working with the same available data as you would be, so I advise you to seek out multiple sources and trust them if it appears correct. I don't remember what I found the wheelbase to be nor will I look for it right now.

I'm afraid I simply can't justify the time to participate. When I said I can answer questions, I mean here and there general questions. I can't make your car with you step by step. I have my own mods, and my own hobbies and aspirations which I've choosen to use my free time on instead of doing this car, for the time being.

Good fortune in your endeavours and please, try to read the book I suggested, at least.

 

[Luis Mercury]

While I am reading the book ... Can you put the links or sources of all this information? It would be very important to accompany the development of the project.
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I want to remind you that doing the step by step will allow me to justify because we take the excellent base of your Skippy