[cdrptrks]

Originally Posted by wakespeak

I just mash the throttle basically all the time in race mode on SC3Rs and I hear it cut throttle when it needs to, eg on corner exit. You can't be stupid with it sure, like on carousels, but almost. On cold tires or mixed wet conditions the PTM can't save you.

Important note: your ZL1 1LE comes calibrated for the 100tw SC3R tires that come with the car. The original poster's SS 1LE is calibrated for less grippy 220tw SC3 tires. In his case, when using PTM the car's expectation of the maximum available grip is lower than what his 3R tire can provide.

When I run 3R tires on my SS 1LE I normally start in PTM Dry or Sport 1 (depending on how cold it is) and change it to the next mode every lap or two and test available grip in slow/safe corners before holding the traction control button down for about 7 seconds to fully turn everything off before going at full pace. I have previously had unexpected big snap oversteer even 3 minutes into warming up the 3Rs with everything off and know of several others who have spun out on them while they're cold. I tried PTM Race at Barber on 3Rs and it works but looking back at the PDR video I was seeing a lot of intervention on corner exits in places where I got no intervention on the stock SC3 tires which means the car was holding back power because of the difference between the tires it is programmed for vs. the tires I was using. I could not feel this intervention while driving. Sometimes I can feel/hear intervention in PTM Race on the SC3 tires but sometimes it is slight enough that I can't. In Sport 1 and Sport 2 I can normally hear and feel any PTM intervention. The % lap time difference between SC3 and SC3R was also a little smaller than I would expect based on other tracks where I didn't use PTM with the 3Rs.

[cdrptrks]

Originally Posted by Christian1LE

I would use regular Supercar 3 tires if you're 10 seconds off the pace, just from an economy standpoint, the non R tires last much longer. You can build good habits with any tire, if you don't care about spending money then you can keep using the R tires

Agreed. For me I think SC3 tires last at least twice as long as SC3Rs so I typically use SC3 for most sessions.

Originally Posted by Christian1LE

the car feels more predictable to me while sliding around with everything off.

Agreed, even when not trying to slide around.

Originally Posted by FactoryMatt

I want to build good habits, but I also want to avoid learning the hard way as much as possible. Hope this all makes sense and thanks in advance!

Unless you have PDR to review session videos to look for intervention, there will be times where PTM intervenes slightly and you can't feel it while driving but if you took the same corner the same way with everything off, you would have to countersteer to catch the slide. The best way to feel what the car is doing is to drive with traction and stability control fully off but there are plenty of tracks I've visited where I used PTM the whole time because there were a lot of barriers close to the edges of the track and I wanted to have an extra safety net. You will have to decide your risk tolerance and whether you want to buy track insurance or not.

If you're planning to use PTM, it should work best with stock tires because they were used for testing and programming the system.

[FactoryMatt]

Originally Posted by cdrptrks

Agreed. For me I think SC3 tires last at least twice as long as SC3Rs so I typically use SC3 for most sessions.


Agreed, even when not trying to slide around.


Unless you have PDR to review session videos to look for intervention, there will be times where PTM intervenes slightly and you can't feel it while driving but if you took the same corner the same way with everything off, you would have to countersteer to catch the slide. The best way to feel what the car is doing is to drive with traction and stability control fully off but there are plenty of tracks I've visited where I used PTM the whole time because there were a lot of barriers close to the edges of the track and I wanted to have an extra safety net. You will have to decide your risk tolerance and whether you want to buy track insurance or not.

If you're planning to use PTM, it should work best with stock tires because they were used for testing and programming the system.

thanks, good insight, but wouldn't SC3Rs on 1LE lead to LESS intervention (once warm) than with stock SC3s?

Hopefully the ECF have a similar enough friction curve to SC3 to keep PTM predictable. I do have PDR. i wish it indicated TCS and yaw intervention separately.

[cdrptrks]

I believe the maximum cornering g force is programmed into PTM based on the SC3 capabilities so if you slightly exceed that number on SC3Rs the system thinks you're sliding when you're not and intervenes unnecessarily on corner exits in this case.

There are probably other inputs besides g force to account for off camber corners but I'm just speculating based on what I saw comparing my Barber PDR videos with SC3 vs. SC3R.

[Christian1LE]

Originally Posted by cdrptrks

I believe the maximum cornering g force is programmed into PTM based on the SC3 capabilities so if you slightly exceed that number on SC3Rs the system thinks you're sliding when you're not and intervenes unnecessarily on corner exits in this case.

There are probably other inputs besides g force to account for off camber corners but I'm just speculating based on what I saw comparing my Barber PDR videos with SC3 vs. SC3R.

I don't know anything about how PTM is programmed but to me I don't think lateral G forces would be accounted for at all, that seems like a poor way to program TC. I would think it's mainly based off of wheel speeds relative to each other. If anything when you start sliding lateral G forces decrease.

[N Camarolina]

Originally Posted by FactoryMatt

I do have PDR. i wish it indicated TCS and yaw intervention separately.

The PDR does indeed indicate yaw intervention separately from TCS. True that when you playback the simple video recording from the PDR that you will see one single symbol on the screen to indicate that TCS or stability control has activated (with no way to tell the difference), but the video playback is just touching the surface of the data that is recorded and available from the PDR. Perhaps you are not aware of the capabilities of the PDR?

You need to use the PI Toolbox software (free) in order to see all the sensor data. Let me know if you are interested in want help with this.

I've been driving in Sport1, but with the goal of staying just below the yaw rate that is needed to activate stability control and just below the throttle input needed to activate TCS. I can verify this when I later download the PDR data and view it in PI Toolbox and look for instances where either system activated and then consider the video and other data circumstances that led up to each of those moments so I can learn what caused it (me at fault, or the computer being too restrictive).

[FactoryMatt]

Originally Posted by N Camarolina

The PDR does indeed indicate yaw intervention separately from TCS. True that when you playback the simple video recording from the PDR that you will see one single symbol on the screen to indicate that TCS or stability control has activated (with no way to tell the difference), but the video playback is just touching the surface of the data that is recorded and available from the PDR. Perhaps you are not aware of the capabilities of the PDR?

You need to use the PI Toolbox software (free) in order to see all the sensor data. Let me know if you are interested in want help with this.

I've been driving in Sport1, but with the goal of staying just below the yaw rate that is needed to activate stability control and just below the throttle input needed to activate TCS. I can verify this when I later download the PDR data and view it in PI Toolbox and look for instances where either system activated and then consider the video and other data circumstances that led up to each of those moments so I can learn what caused it (me at fault, or the computer being too restrictive).

thanks, might take you up on that. would be interesting if you can graph out inputs against Gs against slip to see what correlations you find when excessive yaw is produced. i'd guess this is what race teams do? i have some books to read... hard to control for surface camber and such though.

[wakespeak]

Originally Posted by cdrptrks

Important note: your ZL1 1LE comes calibrated for the 100tw SC3R tires that come with the car. The original poster's SS 1LE is calibrated for less grippy 220tw SC3 tires. In his case, when using PTM the car's expectation of the maximum available grip is lower than what his 3R tire can provide.

When I run 3R tires on my SS 1LE I normally start in PTM Dry or Sport 1 (depending on how cold it is) and change it to the next mode every lap or two and test available grip in slow/safe corners before holding the traction control button down for about 7 seconds to fully turn everything off before going at full pace. I have previously had unexpected big snap oversteer even 3 minutes into warming up the 3Rs with everything off and know of several others who have spun out on them while they're cold. I tried PTM Race at Barber on 3Rs and it works but looking back at the PDR video I was seeing a lot of intervention on corner exits in places where I got no intervention on the stock SC3 tires which means the car was holding back power because of the difference between the tires it is programmed for vs. the tires I was using. I could not feel this intervention while driving. Sometimes I can feel/hear intervention in PTM Race on the SC3 tires but sometimes it is slight enough that I can't. In Sport 1 and Sport 2 I can normally hear and feel any PTM intervention. The % lap time difference between SC3 and SC3R was also a little smaller than I would expect based on other tracks where I didn't use PTM with the 3Rs.

Yes, points well made, the SS 1LE's PTM I would safely assume is designed for the stock tires and brakes. Change the parameters and the system can't make the right decisions. Hence for the OP starting with the SC3 (not R's ) and stock brakes is recommended to make the most of the PTM.

I have spun out on cold 3Rs, they must be warmed up. Also seen ZL1 1LE drivers put their cars in the wall on 1st lap out.

Don't know, but likely agree the differences are probably not huge with the 3's vs 3R's, but that's when you get to advanced and start to run the car on the line at its limits.

The 3Rs decline as they're used like most R compound tires. You have a very few really good laps before they fall off. Its a 2s difference for me at COTA between new and slightly used.

[Badmojo]

This is a good point that I hadn't considered. The PTM calibration of my 2019 ZL1 1LE is more aggressive than the calibration on my old 2018 ZL1. I'm referencing both cars on ZL1 1LE sized Goodyear 3R tires.

Originally Posted by cdrptrks

Important note: your ZL1 1LE comes calibrated for the 100tw SC3R tires that come with the car. The original poster's SS 1LE is calibrated for less grippy 220tw SC3 tires. In his case, when using PTM the car's expectation of the maximum available grip is lower than what his 3R tire can provide.