Seen a post by jimmy but that disappeared............ i cant find 295 PS4S here in Syd atm & need new rears. Anyone here with a coupe got 285 PS4S in the rears?? Do they stop wheelspin when taking off??

My car is a PFL, if i keep stock coupe widths will upgrading to 285 PS4S be better for grip than 285 PSS? Thank u mates

 

Man I'm in the same boat haha no 295's here in oz unless you buy second hand goods with no warranty. Subbed.

 

I went from 285 PSS to 305 PS4S and it still spins the wheels. They're better but not a complete fix. I for sure wouldn't bother with 285 - go straight to 305

 

Really? Are you tuned?

 

I have 285 PS4S on my 2019 C63S coupe and I feel no need to go bigger. Bigger just means heavier and more rotational mass to move. It doesn't stop wheel spin completely. That's essentially pretty much impossible on these cars, but they develop much more grip than the stock 285 PSS I had. You don't actually want zero wheel spin for maximum traction. Tires develop their best traction when there is about 10% wheel spin. That causes the compound to really dig into the pavement. In combination with the new 9-stage traction control and ESP in Sport Handling mode, I don't struggle for traction anymore. It maintains just the right level of spin too hook and take off and the car is still playful to do some drifting. The PS4S is short in supply at the moment, though. 285s are on back order here in the USA.

 

Nope stock. It will still spin the wheels easily in 1st and 2nd and all the way up to 4th at 80kmh when it's wet

 

Exactly how I feel.... thx super. With the 285 PS4S are you able to at least mash the pedal in 2nd and not loose traction now??

 

Aren't you the same guy that has never launched it? If you drive like a ***** I'm not surprised you don't spin the wheels.

Got a reference? Sounds like nonsense to me

 

No, definitely not

 

Pretty much. Definitely do still get some wheel spin, but that's fun. With the PSS it spun all the way to third and I had to short shift to get it to hook. I no longer have to short shift now.

LOL! Pretty sure I drive the car harder than most on here. I'm not a drag racer, though. I'm more about track and mostly canyon carving and drifting. 0-60 stop light drag races is not my thing, but yes if that's what you are all about you might wanna get some drag radials .

Do your own homework. It's physics.

 

What relevance does the 9 stage traction control have if you're in Sport handling mode?

 

The first thing you have to understand is that the 9-stage TC is fundamentally different from traditional TC. Traditional TC is reactive. It doesn't do anything until there is wheel spin and then scrambles and tries to forcefully regain traction by applying the brakes and worst case abruptly cut engine power. The 9-stage TC is directly integrated into the engine torque management and it proactively manages the torque and quickly adjust to maintain the desired wheel spin. EVs are the kings in this regard, because they can react super fast and adjust the power sent to the motors to instantly adjust to traction changes. The 9-stage TC comes close to that, but a combustion engine can't react as quickly as an e-motor, but it's a lot better than traditional TC, which is more like brute force. With the 9-stages you can essentially control in about 10% increments how much wheel spin you wanna allow, and it manages the engine torque to keep that wheel spin fairly constant and allow the tires to grip. In Sport Handling mode it selects an appropriate level to allow just enough wheel spin for maximum traction. It goes back to what I said earlier, a little bit of wheel spin helps the tires to hook. When you stomp on the throttle the wheel spin stays at the desired level and the car hooks. The brakes won't come in and desperately try to slow the wheels. TC simply only sends just enough of the torque to the wheels to help them hook up. You can essentially just stay on the throttle and you will notice that the engine rpms stay almost constant initially while the tires spin a little bit and once they fully hook up the engine powers up more and off you go. It's perhaps difficult to describe in a post, but it all comes down to much faster and smarter torque management to get the most out of the tire grip and not consume the rear brakes by forcefully braking the driven wheels. EVs essentially out traction most ICE cars, because of how quickly and precisely they can control wheel torque, and the 9-stage TC does the same with an ICE. The reason for the 9-stages is so that if you are more proficient on the track, you can dial in just the right amount of spin for a given track or if you are really good even for a specific corner in order to power out of the corner with maximum traction. Some corners are faster with a bit of wheel spin, while others are faster w/o wheel spin. This system comes straight from GT3 racing.

 

Good info mate, thanks. Swiss the 285 PS4S tires are actually a bit wider than the 285 PSS aren't they?

 

That's correct. They are a tad wider and look less stretched on the rears.

 

Here's my car with P4S 305 Rears, no rub ever since i took the spacers off. Running stage 1 DME and yes I spin all the way to third. I wish I bought R888R's again but I wanted to try the P4S.

 

Thanks again Super. Yep definitely a bit wider and more contact patch. Here's a comparison by one of the guys on the F80 M3 forums.

Left 285/30/20 PS4S
Right 285/30/20 Pilot Super Sport


Left 285/30/20 PS4S
Right 285/30/20 Pilot Super Sport


Left 285/30/20 PS4S
Right 285/30/20 Pilot Super Sport

 

thx boys........ gosh no one in oz has these tyres it seems.......... been ringing around