Plaid Drag Racing - Not such a great night

[HighPotential]

The Sapphire's traction control is considered one of the best in the industry. And with cars this torquey, that makes a difference. I did notice though that the Sapphire was able to pull on the Tesla, but not assertively. The race is won in the first second.

That's why if I ever get next to one, I will be on my reflexes and will have a good chance of beating it.

 

[terranx]

Brooks made a point that they were at a private rental of the track and that the track had extra prep on it. He showed how much his shoes stuck to the track. That doesn't really help the Plaid since its traction control is preprogrammed for factory tires on asphalt. Track prep helps to some degree to prevent extra tire slip which causes the traction control to severely cut torque, but it doesn't allow more than the preprogrammed torque.

The Sapphire may have more of an active traction control that can take advantage of the extra tack of the extra prep applied to this track. In the video of the Sapphire on the Tesla Racing Channel, it performed badly on its factory tires and normal track prep. So the Plaid just might take the Sapphire at a light.

Tesla did that to get their 1.99 time too. The traction control is always active and can take advantage of better grip.

 

[TIppy]

Tesla did that to get their 1.99 time too. The traction control is always active and can take advantage of better grip.

It's well known that Tesla has a pre-programmed torque curve under max acceleration that is optimized for the factory tires on asphalt. It is active in the sense that if the tires start to spin while using the preprogrammed curve, the torque is reduced from the pre-programmed value, rather drastically.

Decreasing the weight of a Plaid can actually decrease performance on asphalt as the preprogrammed torque causes the tires to break free causing the torque to begin cycling.

 

[terranx]

It's well known that Tesla has a pre-programmed torque curve under max acceleration that is optimized for the factory tires on asphalt. It is active in the sense that if the tires start to spin while using the preprogrammed curve, the torque is reduced from the pre-programmed value, rather drastically.

Decreasing the weight of a Plaid can actually decrease performance on asphalt as the preprogrammed torque causes the tires to break free causing the torque to begin cycling.

If that were the case, the car wouldn’t get better times on prepped tracks and would also have a very hard time dealing with max acceleration with lesser tires, cold weather, etc.

 

[TIppy]

If that were the case, the car wouldn’t get better times on prepped tracks and would also have a very hard time dealing with max acceleration with lesser tires, cold weather, etc.

Under the programmed torque, due to varying road conditions, the tires do occasionally start to spin. When this happens, the torque isn't just decreased slightly. It is drastically reduced to allow the tires to regain grip. Then the torque is relatively slowly brought back up to the programmed value. You can feel this torque cycling in the car when it happens. The prepped track makes it less likely the tires will spin while following the pre-progammed torque curve, so the torque won't get drastically reduced. The prep does not however allow more than the pre-programmed torque.

The car does struggle with lesser tires and cold weather, in that max acceleration is reduce via this torque cycling problem.

 

[TIppy]

The Sapphire's traction control is considered one of the best in the industry. And with cars this torquey, that makes a difference. I did notice though that the Sapphire was able to pull on the Tesla, but not assertively. The race is won in the first second.

That's why if I ever get next to one, I will be on my reflexes and will have a good chance of beating it.

You can see from the side-by-side draggy results that the Sapphire and Plaid have the same acceleration after about 1.7 seconds and 50 mph. The speed difference actually drops slightly after that from 8 mph to 7 mph. It's early on where the Sapphire is pulling 1.5 gs vs the Plaids 1.3 gs that the Sapphire gains its advantage. It won't be able to do that on an unprepped suface.

 

[terranx]

Under the programmed torque, due to varying road conditions, the tires do occasionally start to spin. When this happens, the torque isn't just decreased slightly. It is drastically reduced to allow the tires to regain grip. Then the torque is relatively slowly brought back up to the programmed value. You can feel this torque cycling in the car when it happens. The prepped track makes it less likely the tires will spin while following the pre-progammed torque curve, so the torque won't get drastically reduced. The prep does not however allow more than the pre-programmed torque.

The car does struggle with lesser tires and cold weather, in that max acceleration is reduce via this torque cycling problem.

I mean I can literally get full power down to the ground without perceptible spin or traction control intervention in freezing temperatures. That wouldn’t be possible with 1k hp unless the traction control was a lot more sophisticated than you claim. I have felt the car spin the wheels, but it’s rare.

 

[Sam1]

You can see from the side-by-side draggy results that the Sapphire and Plaid have the same acceleration after about 1.7 seconds and 50 mph. The speed difference actually drops slightly after that from 8 mph to 7 mph. It's early on where the Sapphire is pulling 1.5 gs vs the Plaids 1.3 gs that the Sapphire gains its advantage. It won't be able to do that on an unprepped suface.

Yep, the lucid lacks pretty bad on no prep. Tesla's system is good enough where I hit 1.3g on prepped and no prep consistently.

 

[TIppy]

I mean I can literally get full power down to the ground without perceptible spin or traction control intervention in freezing temperatures. That wouldn’t be possible with 1k hp unless the traction control was a lot more sophisticated than you claim. I have felt the car spin the wheels, but it’s rare.

People complain all the time that they fail to hook on a prepped track, when it isn't fresh, and can feel the torque get cut way back. It may not be "sophisticated", but it's optimized to perform on unprepped roads. This approach means the wheels seldom spin, where as an active system is constantly oscillating around the peak traction point of the tires and therefore its average traction is considerably less than peak. Tesla tries to keep the torque just below the peak torque the tires can handle.

 

[Sam1]

People complain all the time that they fail to hook on a prepped track, when it isn't fresh, and can feel the torque get cut way back. It may not be "sophisticated", but it's optimized to perform on unprepped roads. This approach means the wheels seldom spin, where as an active system is constantly oscillating around the peak traction point of the tires and therefore its average traction is considerably less than peak. Tesla tries to keep the torque just below the peak torque the tires can handle.

If only I had hundreds of dragy logs showing how the car reacts to bad launches and still gets 9 second 1/4's ...

Most people can't "perceive" the spinning or nerfing because it happens so quickly. But, it needs to be remembered that, traction control isn't triggered until the tires are spinning. So, no matter what, the situation starts with excess wheel speed.

And on and on...

 

[WilliamG]

Again solidifying your ignorance about racing by focusing on an irrelevant point.

I mean okay, that’s certainly one take.

 

[Sam1]

I mean okay, that’s certainly one take.

It's the accurate take. You ignored the entire post, and focused on an et, which was never the point, or matters in the context whatsoever.

 

[WilliamG]

It's the accurate take. You ignored the entire post, and focused on an et, which was never the point, or matters in the context whatsoever.

No, I focused on how you had no traction longer than I’ve seen any Plaid at the strip experience - as your argument.

 

[NeuroRad]

I mean I can literally get full power down to the ground without perceptible spin or traction control intervention in freezing temperatures. That wouldn’t be possible with 1k hp unless the traction control was a lot more sophisticated than you claim. I have felt the car spin the wheels, but it’s rare.

I don’t buy it. Plaid is a different beast in warm/hot temps. Plaids TC can be extremely insidious and you won’t “feel” anything but you’ll be slower.

 

[Christopher1]

Plaid is traction limited? Why does the plaid have such a slow start compared to P85D P90D etc? Look up the power curve from the launch event..
And often people get the rear to spinn because the front don't follow etc. Worst AWD ever.

 

[terranx]

I don’t buy it. Plaid is a different beast in warm/hot temps. Plaids TC can be extremely insidious and you won’t “feel” anything but you’ll be slower.

Maybe it’s not quite *full* power but I do have logs showing 950-1000hp in 30 degree temps. But that’s my point, it’s not a dumb traction control system with very aggressive power cuts like the other guy is claiming. It’s dynamically adjusting to available grip

 

[Kohley]

It's not an assumption. Here is one of many completely random videos of my car at the track, you can hear it spinning up until a little before the 330' mark (before it migrates into the typical tread noise), at which point I'm normally somewhere around 80-90mph depending on the tire setup. The reason people don't think these cars are spinning on the street is because there's no smoke and/or there's not much noise. It's not blowing the tires off at 80mph, it's just spinning a little. You can hear it at the track and not on the street is because there's rubber everywhere and it screeches when slip occurs between two hard rubber surfaces. It doesn't make much noise when the drag radials are on because they slip less and the compound is much softer than the track surface.

Cars at the dragstrip are not faster solely because they have more power. No offense meant, because not everyone is into racing, and may not understand basic things about it.

Kind of goes over into the brake discussion as well. I have datalogs on dragy showing how bad the OG OEM pads are compared to PFC pads and then CCBs on high speed stops. I don't post data because the next excuse would be something like "but the air temp was 4 degrees warmer" or " how do we know you weren't on semislicks?" etc.

I can get the ABS to engage instantly at 100+ mph on stock brake pads, until the pads overheat after repeated stops, better brakes wont stop the Plaid any faster, but stickier tires would indeed.

 

[NeuroRad]

Maybe it’s not quite *full* power but I do have logs showing 950-1000hp in 30 degree temps. But that’s my point, it’s not a dumb traction control system with very aggressive power cuts like the other guy is claiming. It’s dynamically adjusting to available grip

Yep, you have to wonder if they even own a plaid claiming that. Its an extremely sophisticated TC system and really nothing like a traditional system. I also don’t think there’s any evidence lucid tc system is better. I believe they use a bosch system as they couldn’t figure it out themselves

 

[cptnslo]

That was just OEM 19 tires/wheels. But I have runs on those, OEM 21, OEM 21 wheels with pirelli nf0, then na0, then na0 rears and lm1 pirelli, then nf0 goodyears, then aftermarket 21 wheels with OEM PS4S, and na0 pirelli rears with lm1 fronts. Then for radials, nitto rears and pirelli t0 19 on the front.

have tried quite a few setups just to test stuff out because of curiosity.

For the noodles where the NT05 or the 555r

 

[TIppy]

Maybe it’s not quite *full* power but I do have logs showing 950-1000hp in 30 degree temps. But that’s my point, it’s not a dumb traction control system with very aggressive power cuts like the other guy is claiming. It’s dynamically adjusting to available grip

P85D wheel spin on acceleration. Red curve is rear torque, green is front torque. Notice how it drops quickly and slowly climbs back to programmed torque. These curves should be flat in this region.

In case you think this has changed, watch the video at the included link. These guys have massively stripped a Plaid and 0 to 60 i worse. Active traction control would have compensated for the reduced weight. He says he could feel the car fighting for traction.

I do own a Plaid but don't see how that has any effect on this discussion.