Remembering back, I thought it would be a neat idea to do the same test for the new tyres that I did back in this thread. The difference between tyre compounds is now bigger and smaller at the same time; R2 to R4 tyres now have very similar grip levels while the temperature ranges are further apart, but see for yourself.

As I've done in the last thread, I cannot stress enough that these values are all taken by eye and feel and might not represent LFS' real behaviour 100%.

The procedure to take the values was driving around the autocross area in a normal setup with the tyres heated to the desired temperature. Each tyre compound was tested in five temperature "areas" (cooled down - start temp - optimum temp - hot - cooked).
After driving a few circles with the intent to get maximum grip values, I extracted the RAF data from the replays and viewed them in the "slip angle vs. lateral grip" graph of the RAF Tyre Extract tool. Finally, I noted them down and plotted them to the excel sheet graphs, modifying the values (within reason) to produce nice curves.

The cars used for the values were: R1: FOX, R2-R4: FZR, Road Super: FZ50. Please do note that the R1 graph would've probably looked somewhat different if I had the chance to mount them to the FZR, my guess is it would've been about 0.05g "lower".

Update:
I've now made some tests on the FOX with R2 and R3 tyres, and from the difference to FZR's tyres I was able to estimate how R1 tyres would grip on a FZR, making the R1 curve actually useful. The grip difference is 0.09g to exact. Also at the new test, the R1 tyres didn't seem that peaky anymore, flattening the curve somewhat (read: R1 tyres have less grip falloff when too cold/hot now).

Enough talking, here's the graph:

Lovely work, Android - very interesting indeed. The new range of compounds certainly make for more interesting choices.

nice, the road super and harder slicks happens to be more linear in drop of performance when being overheated.

very nice graph indeed.

Thanks

For reference, here's the old graph of patch Q (and prior)

I too noticed this, can get mega braking deceleration in the slick cars now.

So...

Tyre Temperature Compound choice
<86deg R1
87-95deg R2
96-114deg R3
115deg+ R4

Or can excel or whatever give you more accurate points for where the curves cross?

The points are accurate enough - R3 only go to 110, though. The temperature value is in the center of the two | |, as can be seen by the blobs on the curves. They represent the data points in 5°C steps.

wow, nice.

How did you do this?

Very good work. It's simply awesome how much data one can get out of this amazing simulation. Simply awesome.

excellent stuff!
If you're ever feeling inquisitive again, a few graphs of pressure vs grip for the various compounds would also be very interesting...

^^^ Good idea! I'll try a test run later today, alteast R2-R4 running @ optimum temps with varying tyre pressure. The question is how much that graph is going to tell us, apart from lower pressure = more grip, because I cannot factor something like stability or race-usability into it. But we'll see

I asked because I'd be interested to see the difference in pressure required before r3 had more grip. racing at so long last night in the xrr had me running 95 degrees on certain tyres, perhaps running lower pressure and being able to push harder on r3's would have been worthwhile.

As far as i see atm there is no need to put r3's on for most tracks (with GTR and Fo8). The R2 tyres will eventually overheat for some laps but when the temp come down again you will pull laptimes that are way faster then with R3's. Example: Blackwood Fo8 - R2's are good for 5 laps then they overheat and about lap 12-15 they start to cool down and laptimes will drop dramaticaly. About lap 20 you're gonna be way faster then with R3's. And I'm even sure that with the right race setting this tyre overheating won't be too dramatic. Well tyre physics are better then before but I would have liked to see an increase of tyre wear for this patch and not a decrease like we have it now. It removes the strategic component for longer races, would have been nice to have the possibility to run on R3's vs R2's in such races. Just like you see in real life, one team takes a harder compaound and others decide softer compound, both are fast in different ranges, harder compund = more stable over time, softer compound = faster when on opt temps but with prob of overheating and faster wear. Ok r3's last longer but for FZR you can drive a full tank dry with R2's. And I read somewhere here that with XRR R2 tyre will blow before running dry but R3's are too slow.

yeah... i drove like a maniac for 10 laps with the XRR on blackwood with r3 tires... and they were barely warmed up by the end of the race

i was using a setup optimised for r2 tires tho...

lrb, this was for a series of 10 lap sprint races, pushing extremely hard and with a fair bit of oversteer necessary for my setup and driving style... so yeah, not quite as clear cut.

And to continue your great tests, please add a chart showing the grip differences with different camber angles (no camber, low, med, high, very high) just to see how much it affects cornering... I sometimes wonder how drivers can go so fast into sharp turns and by checking their Setups I often see 'excessive camber' combined with rather low tire pressure

A hello to austria

camber isn't really as 'static' a value as the others... highly dependant on vehicle, vehicle setup, tyre type and pressure.

Quote from Blowtus :

camber isn't really as 'static' a value as the others... highly dependant on vehicle, vehicle setup, tyre type and pressure.

you're shurely right, but maybe there's an optimal setting in camber pulling the most g's? I dunno

there is but that value is highly dependant on everything I mentioned - whereas with pressure, grip, tyre type etc, it's either not at all dependent or only very lightly so.

Did a quick test of the R2 tyres' pressure dependence, again at the autocross area. Tyres were heated to optimum temperature (85°C) and set to a what I think normal camber setting (live camber at -2.45°). The result was pretty linear - I attribute the wigglyness to measuring error. Basically, the less pressure, the more grip you have.

Actually I'm a bit surprised by the result. I thought that running the slicks on 80kPa is going to yield a worse result than at a more reasonable pressure, because of all that tyre rolling over (the outside heated quite faster than the inside).

I may test other tyre compounds later, but I really doubt they show any difference other than the line being offset a bit.

Most useful information I read in this this forum so far... excellent work!

Funny tyre pressures you have there. Sure you don't mean kPa?

D'oh :doh:

E: What are you talking about?

very interesting. according to that r3's should be approximately the same grip as r2's, (both at optimum temp) if the r3's are around 7psi lower.

Is the comprison between R1 and R2 reliable when the readings were achieved with different cars?
Anyway, great work.

Vain