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I've run our cars through vdrift -cartest looking into brake performance, mainly fixing friction coefficients to have more realistic values (0.3 - 0.7) and increasing brake system pressure where required.

There are a few cars that should have much more aggressive brakes now.

I've ran into one interesting case. TC (Toyota Celica ST185 Rally) reports
60-0 stopping distance (no ABS): 124.708 ft
60-0 stopping distance (ABS): 2326.04 ft

No idea what is going on with the ABS there, will look into it.

EDIT:
There are also a few cars with max power not matching torque curve it seems, which results in incorrect top speed estimation.
The issue with the Celica turned out to be a non issue Wink

I've added some engine rev up code to the testing logic, which happened to interfere with braking commands for some cars, depending on their transmission setup.
NaN Wrote:I've run our cars through vdrift -cartest looking into brake performance, mainly fixing friction coefficients to have more realistic values (0.3 - 0.7) and increasing brake system pressure where required.

I would say that most of the cars are using piston areas that are way too large. In the project I am working on, I just reduced the suggested value of 0.015 m2 to 0.00501, which is that of a pretty impressive 6-piston caliper AP Radi-CAL CP9660:
http://www.apracing.com/drawings/2015 Product Catalogue/2015 Brake Calipers.pdf

To compensate, I've set max-pressure to a higher value of 1.4e7 pascals, equal to 140 bars.

That was indeed my adjustment factor when I was testing at the Nordschleife in the hard-braking approach from Tiergarten to Hohenrain:
2.5e7 -- enough stopping power (with ABS)
1.1 ---- too little
1.5 ---- enough
1.3 ---- too little
1.4 ---- enough

Pressures up to 250 bars are at least within the realm of possibility:
https://www.fte-automotive.com/aftermark...ester.html

On the other hand, I have never heard of a piston area of 150 cm2. The largest I have found are 70 cm2 -- intended for 410mm disks!

I know there are some 8-piston calipers out there, but I don't think they can cover that much.
(12-14-2015, 08:57 AM)arturo Wrote: [ -> ]
NaN Wrote:I've run our cars through vdrift -cartest looking into brake performance, mainly fixing friction coefficients to have more realistic values (0.3 - 0.7) and increasing brake system pressure where required.

I would say that most of the cars are using piston areas that are way too large. In the project I am working on, I just reduced the suggested value of 0.015 m2 to 0.00501, which is that of a pretty impressive 6-piston caliper AP Radi-CAL CP9660:
http://www.apracing.com/drawings/2015 Product Catalogue/2015 Brake Calipers.pdf

To compensate, I've set max-pressure to a higher value of 1.4e7 pascals, equal to 140 bars.

That was indeed my adjustment factor when I was testing at the Nordschleife in the hard-braking approach from Tiergarten to Hohenrain:
2.5e7 -- enough stopping power (with ABS)
1.1 ---- too little
1.5 ---- enough
1.3 ---- too little
1.4 ---- enough

Pressures up to 250 bars are at least within the realm of possibility:
https://www.fte-automotive.com/aftermark...ester.html

On the other hand, I have never heard of a piston area of 150 cm2. The largest I have found are 70 cm2 -- intended for 410mm disks!

I know there are some 8-piston calipers out there, but I don't think they can cover that much.

Yeah, would be nice to have this fixed too (even if it doesn't matter much for the sim: force = area * pressure). I am all for more realistic values.
Hello folks.