Tire Pressure Question

[Torv]

On my long and happily forgotten Tesla, the suggested tire pressure was in the high 40’s PSI. On my Taycan 4S, the recommended tire pressure according to the door frame sticker is 39 PSI. It seems to me that the Taycan will have increased range at a higher PSI. With that in mind, do you all follow the recommended tire pressure according to the placard or do you run higher PSI and if so, are you seeing greater range or w/m efficiency? By the way, I’m running the stock summer Michelin Pilot Sport tires which the Michelin tech specs indicate a not to exceed 50 PSI.

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[TXAG]

I don't run at a higher PSI than recommended because the center of the treads will wear out faster, and Taycan tires wear out quickly enough as it is. Summer treads are thinner when new than all-season treads, too.

Maybe your Tesla had skinnier tires and needed higher pressure to support the weight ...

 

[WattTurbo]

It must varies with tires or rim size because my sticker shows mid 40’s

 

[gnop1950]

The suggested tire pressure on my 21" Goodyear Eagle F1s is 41 PSI front and 44 PSI rear. That will go up, especially in the Arizona summer, once I'm driving by 3 or 4 PSI.

 

[Torv]

I don't run at a higher PSI than recommended because the center of the treads will wear out faster, and Taycan tires wear out quickly enough as it is. Summer treads are thinner when new than all-season treads, too.

Maybe your Tesla had skinnier tires and needed higher pressure to support the weight ...

My Model S had big fat 20“ Michelin tires. I can’t remember if they were Pilot Sport, but that car was as heavy as the Taycan.

FYI—I have increased the PSI to 42. We’ll see if it makes any difference.

 

[Kingske]

My suggested tire pressure is 39 psi in front and 38 psi in the rear but I tend to run those a little higher (41 front and 39 rear) because it improves range a bit without distorting the tire.

 

[Archimedes]

I run 40 cold all around on 21 PZeros. Would only go higher if the car was loaded down for a trip.

 

[outie]

My GTS with 21” RS Spyder wheels show 41 front and 45 rear. The car currently shows I am -3psi on each which is around 36psi now. I pumped 3psi to each and all 4 wheels show 41 now according to PCM, with 0psi difference from target. Is that right? Isn’t the rear supposed to be 45 according to the door plate? The PCM vehicle/TPMS setting is correctly set up as RS21 summer tires.

 

[f1eng]

I always use the recommended tyre pressure.

Higher will reduce rolling resistance but also give a smaller contact patch so reduce grip, which for most people will only be an issue in an emergency stop or swerve, but that is when you need it most.

FWIW in the setup of a Formula 1 car it is one of the first order influences on grip and handling.

 

[Torv]

I always use the recommended tyre pressure.

Higher will reduce rolling resistance but also give a smaller contact patch so reduce grip, which for most people will only be an issue in an emergency stop or swerve, but that is when you need it most.

FWIW in the setup of a Formula 1 car it is one of the first order influences on grip and handling.

True. But I’m not suggesting Hunter S. Thompson's tire pressures exceeding 60lbs PSI on his Great White Shark Cadillac as it speeds down I-15 towards Vegas in Fear and Loathing. I'm simply exploring a modest 10-12% increase for greater efficiency and pressures well below the recommended maximum.

 

[f1eng]

True. But I’m not suggesting Hunter S. Thompson's tire pressures exceeding 60lbs PSI on his Great White Shark Cadillac as it speeds down I-15 towards Vegas in Fear and Loathing. I'm simply exploring a modest 10-12% increase for greater efficiency and pressures well below the recommended maximum.

That may be a "modest" 10-12% reduction in grip, though I would need the tyre curves to know exactly. On the F1 car I worked out the optimum pressure for each circuit during testing based on a near linear relationship between pressure and grip with limitations being tyre damage on fast circuits.

On the F1 car 1 psi change in pressure was significant.

A lot of F1 drivers used to start giving a commentary on the car handling on the slow down lap in practice but I learned not to change the car until the tyres were all at the correct pressure (which I was the engineer defining) since it dominates everything.
I was told Senna, one of the few great drivers I never worked with unfortunately, would not even comment on the car handling until the tyre pressures were right so he knew it too.

I suppose if you are more interested in longer range on highway driving and you are prepared to take the safety risk and aren't going to "drive it like a Porsche" that is fine but you asked for opinion and I gave you mine based on decades of experience getting the best out of a performance car.

You sought opinion, I would never do it myself.

 

[f1eng]

It must varies with tires or rim size because my sticker shows mid 40’s

It depends on tyre make too.
The recommended pressures on my Ferrari are:-
36/32 for Bridgestone
27/31 for Michelin
32/29 for Pirelli
38/33 for Goodyear
This is all for the same tyre/wheel size and the variation was a surprise, even to me, but I am sure the chassis and tyre engineers worked together to get the optimum.

 

[WattTurbo]

It depends on tyre make too.
The recommended pressures on my Ferrari are:-
36/32 for Bridgestone
27/31 for Michelin
32/29 for Pirelli
38/33 for Goodyear
This is all for the same tyre/wheel size and the variation was a surprise, even to me, but I am sure the chassis and tyre engineers worked together to get the optimum.

This is a surprise to me, but now that I analyze what you say it makes sense. When I learned early on to look at the label on the car and not use the max PSI on the tires, I thought it’s the same PSI for the car regardless of tire. Pirellis are on mine now and I planned on switching to Michelin when they wear out. So how do I know what PSI to use? Same with my 991 C2S. I guess I did wrong all these years since I followed the label even after I switched over to Michelin. Any advice?

 

[tigerbalm]

I always use the recommended tyre pressure.

The only time I've gone higher on the recommend tyre pressure – was adding 0.2 bar more to my winter tyres in Ireland for my arctic road trip.

So that with the colder outside temperature when I reached Norway it was at optimum and it saved me messing about with it when I got there. I still felt like I was being lazy and did the wrong thing – especially as I was slightly over pressure for fast autobahn sections.

 

[Torv]

That may be a "modest" 10-12% reduction in grip, though I would need the tyre curves to know exactly. On the F1 car I worked out the optimum pressure for each circuit during testing based on a near linear relationship between pressure and grip with limitations being tyre damage on fast circuits.

On the F1 car 1 psi change in pressure was significant.

A lot of F1 drivers used to start giving a commentary on the car handling on the slow down lap in practice but I learned not to change the car until the tyres were all at the correct pressure (which I was the engineer defining) since it dominates everything.
I was told Senna, one of the few great drivers I never worked with unfortunately, would not even comment on the car handling until the tyre pressures were right so he knew it too.

I suppose if you are more interested in longer range on highway driving and you are prepared to take the safety risk and aren't going to "drive it like a Porsche" that is fine but you asked for opinion and I gave you mine based on decades of experience getting the best out of a performance car.

You sought opinion, I would never do it myself.

Thanks for the thoughtful response. I will yield to you on this as your experience vastly exceeds mine on the subject.

On a related note, as a former bicycle racer, I too was obsessed with tire pressure and could feel a few PSI difference in the ride. I could also “feel” a few millimeters difference in seat post height which drove me bonkers.

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