Of course, I have studied physics, more than some, so I thought I knew everything about auto tires. After all, how could a wider tire make any difference? The 'laws of physics' say that the 'contact area' of a specific mass is irrelevant when it comes to friction. After all a smaller contact area gives a larger pressure per sq cm, so it all balances out. When it comes to tire material, how could it matter that much? Even with F-1 race cars, the material in the tires only makes a small difference, so should it not be the same with a sports car? I, for many years, held to this opinion, and when I got my first Porsche (924) I didn't think twice that it had some new passenger car rated tires on it at first. For normal driving, they were just fine, and as long as I drove my Porsche like a regular passenger car, all was well. Unfortunately, I would 'push' the car, as it seemed to invite me to do, and I often went nearly out of control. I adjusted everything that I could, to no avail. Then a friend told me to change my tires. Why? I had a year or two left on them? But I did, anyway. WHAT A DIFFERENCE! The Porsche cornered and stayed in control in the most extreme circumstances. It was safer and most fun to drive! Yet, what 'physics' was used to get this?
I've had a similar issue with the soles of my boots, they vary a lot when it comes to grip, I can only think it's to do with very complex rubber physics
Well it could be when you turn the maximum load goes to the outer edge. The wider the tire the less the leverage diameter to width.
You should really be careful discussing automotive tires and making some kind of poor analogy. I feel confident in saying modern tires are something you know very little about. They are well understood by the engineers and organizations that have poured billions of dollars in R&D into developing them. All the reasons for your experience are certainly well described by our current understanding of physics. Saying the material only makes a small difference is completely wrong and laughable. Have you watched an F1 race in the last 30 years?
When it comes to speaker cables, it's like tires on cars. If you are driving a Porsche, would you put cheap tires from Sears and expect it to perform its fullest capacity? Of course not. When you have a sports car equivalent of stereo system, you wouldn't want cheap pair of speaker cables from local hardware store, would you? This is when high end speaker cables over $1000 a pair is used. Oh, and don't forget to let them burn-in before evaluating their performance just like car tires need to be warmed up before testing. 😀
My primary criteria for good sound is accurate (perhaps ts better for me to say ‘good imaging’ because I don’t know if it’s accurate) and good LF and HF extension.
This means the speakers have to be up to the job and so does the electronics (source and amplification).
Unfortunately, the other elephant in the room is the recording itself - more often than not nowadays, not up to the job.
I have lot of Santana CD’s (and vinyls) and one of their best was Abraxas. Beautifully recorded with great imaging, space around the performers and little or no excessive compression. Ditto some of the classical CD’s - the best one I have is one with the New York Philharmonic and the Columbia Philharmonic conducted by Leonard Bernstein doing some of his stuff and some George Gershwin - absolutely holographic.
This means the speakers have to be up to the job and so does the electronics (source and amplification).
Unfortunately, the other elephant in the room is the recording itself - more often than not nowadays, not up to the job.
I have lot of Santana CD’s (and vinyls) and one of their best was Abraxas. Beautifully recorded with great imaging, space around the performers and little or no excessive compression. Ditto some of the classical CD’s - the best one I have is one with the New York Philharmonic and the Columbia Philharmonic conducted by Leonard Bernstein doing some of his stuff and some George Gershwin - absolutely holographic.
I've most of Santana's stuff too, saw him at the NEC in Birmingham many years ago, there were angels above the stage which he draw the audiences' attention to 😀. Zappa's albums are a great test too. Which Bernstein recording is that?
I watched one (F-1 race) yesterday, did YOU? The ONLY thing stated between 3 sets of tires available was 'time around the track'. So some were slightly grippier than others, but then they wore out before the end of the race. Let's get real, how many of you critics out there have actually studied physics for real?
Really John, you call an appeal to the laws of physics an "insult", nicely put by a physicist/engineer. Have you burned down your diplomas, just in case?
I did watch highlights (not live), too bad about Leclerc. If you believe the difference in tire compounds are minimal then you are ill informed. When was the last time you tracked a car?
No one, I mean no one, believes that all tires perform the same. Tires are one of the biggest discussion points on car forums.
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Now we need The Tire Thread. Racing tires are not like street tires, but they certainly have multiple compounds to choose from. Rubber compound, tread thickness, belts, sidewall construction, tread grooves or lack thereof, casing material... There are so many factors affecting performance. Heat dissipation is huge, whether road or track. Rubber compounds have a coefficient of friction that varies with temperature, and friction creates heat, so that heat has to go somewhere. The tread has to stay flat on the road and not squirm around, but that means the sidewalls have to give in a controlled way, and that also generates heat. Inflation pressure matters, and also varies with temperature.
John, your "analysis" of the importance of tires on your Porsche was not based on physics. High-school physics would give you the tools to understand at least some of the factors affecting automotive tire performance, but you ignored them. You might as well have said brake disc size doesn't matter, as friction force is proportional to coefficient of friction and applied pressure (ignoring heat, wear, materials, etc.).
Just curious, what kind of tires did you put on the 914 to get decent performance?
John, your "analysis" of the importance of tires on your Porsche was not based on physics. High-school physics would give you the tools to understand at least some of the factors affecting automotive tire performance, but you ignored them. You might as well have said brake disc size doesn't matter, as friction force is proportional to coefficient of friction and applied pressure (ignoring heat, wear, materials, etc.).
Just curious, what kind of tires did you put on the 914 to get decent performance?
You can put that in Analog Source, since some people believe their turntables have extraordinary lubrication requirements.
I did, and still do. I'm not sure what physics laws you were referring to. One of the things I recall (possibly from a material's science class in high-school) is that the coefficient of friction for rubber on a surface like a road has an inverse dependence on contact pressure. Hence big tyres.
Also, different cars having different suspension setups respond to tires differently, one trye may work really well on one car, and poorly on another model of car made a a different manufacturer.
Someone I knew some years ago put an R rated tyre on his street car, illegal tread in 1500 fun miles.
Someone I knew some years ago put an R rated tyre on his street car, illegal tread in 1500 fun miles.
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