Nizer

What is the maximum threshold brake pedal pressure that you guys have recorded in your Cup? Trying to set up a sim to replicate a 991.2 Cup as closely as possible. Thanks.

SkeerRacing

60bar is what my initial peak pressures get to on average with normally anything more leading to front or rear lockup depending on bias, now that amount is very brief before I start bleeding off the pressure as I trail into the brake zone.
If the car has ABS, I try to bend the pedal.

Nizer

That makes sense. I'd read somewhere else that max was around 800psi and 60 bar converts to 870. Thanks for the quick response.

Matt Romanowski

Remember that is line pressure, not pedal force. You can do the math if you have caliper piston sizes, mc size, and pedal lever measurements.

SkeerRacing

Or Just do it by feel

stujelly

i thought the line pressure was like 1100 to 1200 psi

Nizer

Thanks Matt. Finding it a little confusing trying to convert real world braking data to sim world. Some background: been working with the folks at VR Motion Labs (https://www.vrmotionlabs.com/) to put together a sim platform to replicate my Cup. VR Motion are doing some really interesting stuff and their platform is very good at replicating the actual driving experience. That said, the one area that hasn't been translating well for me is brake pedal feel. It's been difficult to get adequate brake pedal pressure or feel that replicates reality with the pedal set being used. The challenge in analyzing alternative pedal sets is that they all quote kg/lb numbers while real car data is expressed in bar/psi.

We're currently looking at Ricmotech GT3 Pro and Heusinkveld Ultimate pedal sets as potential upgrades. The Ricmotech system maxes out at 160kg/350lb load range but that figure doesn't represent brake line pressure, which Ricomtech claims exceeds 1,000psi with their pedal set.

Very much a sim novice here so I've likely butchered half of what I've written.

Somewhat unrelated but cool sidebar video I found today:

CRex

90-95bar peaks on really optimal tarmac and new tires and spec PFC pads. You might be able to take more with less grabby endurance compounds.

We've seen more in the GT3R--some 100-110bars on thick endurance pads. But that comes with a more forgiving pedal and ABS.

If you're looking to accurately replicate that in a sim pedal, you absolutely need a hydraulic setup. Loadcells and springs can't approximate fluid dynamics at the end of the day.

Nizer

Thanks. We've come to the same conclusion.

amso3

I have a bunch of 991.1 (non-ABS) data and the highest pressure I see is 900 psi at Road America. We'll have a new 991.2 at Daytona in a few weeks.

SkeerRacing

90-95? Jesus Christ... That would lock a Yoko instantly haha
Massive +1 on going hydro setup, no other way if you are looking for this level of feel.

CRex

Obviously tarmac-dependent but I suspect there's more to be had in the .1: we'd see 10-15% more, even on green street tarmac (it's hotter here tho). The .1 responds well to a big initial hit of BP. The .2 rewards modulation more--the Junior Program coaches would tell you there's more efficiency over a flatter BP shape...

Yeah Michs N2#s are probably designed for this kind of abuse. Pirelli DHs we've tested to be squishier but not far behind in braking behaviour. Yokos I admittedly have no experience--hope I'll be able to drive the N. American series in time!!

SDGT3

My data shows well over 1000 psi at tracks like Road America and Road Atlanta. Likely Sebring turn 7 also.

neuroguru

1200 psi w/ motorsport ABS quite often.

chas911

On a GT4 Clubsport MR, between 1500-2200ibs of course this is with ABS.

Charlie