Noob questions
I qualified from university 52 years ago so memories are more dark than light . Thanks for the formula correction but as KE increases with the square of speed I still think my multiplier is correct.Wil wrote: ↑Sat Nov 27, 2021 9:37 pmThis isn’t correct btw.On-Track wrote: ↑Sat Nov 27, 2021 11:44 am The Ferodo information was posted to support Rarecolour's argument. Unfortunately it doesn't, it recommends braking from 50mph to 20mph.
One of the basic laws of physics is E=M(C squared) where E is energy, M= Mass and C=velocity. So a mass (in this case a Macan) travelling at 70mph has 400 times the kinetic energy as one travelling at 50mph. The brakes use friction to convert this energy into heat. Ferodo warn that excessive heat can cause irreversible changes to the pad material.
Rarecolour would seem to be right about the initial bedding in but wrong about the speeds involved.
In E=MC^2 C is the speed of light not the speed of a macan.
Kinetic energy is 1/2 mv^2. So @70 you’ve about double the energy of the same vehicle at 50.
Correction: you're right and I'm wrong. KE does increase with the square of speed but you have to subtract 50^2 from 70^2 so at 70 KE is slightly less than double that at 50.
My brain hurts
Last edited by On-Track on Sun Nov 28, 2021 11:30 am, edited 1 time in total.
Peter
Current: 2020 Carmine Red GTS http://www.porsche-code.com/PMST9ZI9
Gone- 2015 Sapphire Blue Diesel
Gone -2013 Cayenne Diesel
Current: 2020 Carmine Red GTS http://www.porsche-code.com/PMST9ZI9
Gone- 2015 Sapphire Blue Diesel
Gone -2013 Cayenne Diesel
-
- Posts: 1428
- Joined: Sat Jan 23, 2021 9:39 am
Get a room you 2
Ex -
Macan Turbo (Mamba Green)
Audi RS6 (Misano Red)
Audi S4 (Silver)
Audi S3 (Imola Yellow)
Peugeot 309 goodwood (Green)
Peugeot 306 gti-6 (Silver)
Peugeot 205 gti (Ltd edition Sorento Green)
Macan Turbo (Mamba Green)
Audi RS6 (Misano Red)
Audi S4 (Silver)
Audi S3 (Imola Yellow)
Peugeot 309 goodwood (Green)
Peugeot 306 gti-6 (Silver)
Peugeot 205 gti (Ltd edition Sorento Green)
With my first Macan (and the Cayenne before it) I had a set of winter wheels for driving in sleet/snow/low temperatures. These days I have no pressing need to be anywhere so I stay at home when the weather deteriorates. BTW, I'm not trying to start a debate about winter wheels as views are just as heated on that topic.Wil wrote: ↑Sat Nov 27, 2021 9:28 pmYou can say that again. I only said the brakes didn’t feel great.On-Track wrote: ↑Sat Nov 27, 2021 10:12 amYour opening post has obviously generated a lot of heat (excuse the pun ) but by now your brakes should have settled in and you should be happy with the performance. Both Mercedes and Porsche brake systems have fairly long pedal travel. The Macan system is heavily servoed so stopping from medium to low speeds only requires a fairly small application. In the (thankfully) few occasions I've had to do a hard stop I always end up looking in the rear view mirror. I have absolute confidence I will stop short of the obstruction in front but don't know if the car behind me can.
Anyway, it’s done a couple of hundred miles now, but I’ve been out today in sleet/snow, so brake testing didn’t seem to be an ideal pastime. Pottering about trying not to crash seemed like a better idea.
I will make sure though that I keep everyone up to date as everyone seems to be quite invested in it.
For the first 5,000 miles or so you might find the engine uses a little oil (some do, some don't) after that oil consumption should be negligble.
Peter
Current: 2020 Carmine Red GTS http://www.porsche-code.com/PMST9ZI9
Gone- 2015 Sapphire Blue Diesel
Gone -2013 Cayenne Diesel
Current: 2020 Carmine Red GTS http://www.porsche-code.com/PMST9ZI9
Gone- 2015 Sapphire Blue Diesel
Gone -2013 Cayenne Diesel
I do like a bit of physics, so much more interesting than most of the dialogues on colour, wheel size and unnecessary twiddly bits! More intellectual stuff please!On-Track wrote: ↑Sun Nov 28, 2021 9:42 amI qualified from university 52 years ago so memories are more dark than light . Thanks for the formula correction but as KE increases with the square of speed I still think my multiplier is correct.Wil wrote: ↑Sat Nov 27, 2021 9:37 pmThis isn’t correct btw.On-Track wrote: ↑Sat Nov 27, 2021 11:44 am The Ferodo information was posted to support Rarecolour's argument. Unfortunately it doesn't, it recommends braking from 50mph to 20mph.
One of the basic laws of physics is E=M(C squared) where E is energy, M= Mass and C=velocity. So a mass (in this case a Macan) travelling at 70mph has 400 times the kinetic energy as one travelling at 50mph. The brakes use friction to convert this energy into heat. Ferodo warn that excessive heat can cause irreversible changes to the pad material.
Rarecolour would seem to be right about the initial bedding in but wrong about the speeds involved.
In E=MC^2 C is the speed of light not the speed of a macan.
Kinetic energy is 1/2 mv^2. So @70 you’ve about double the energy of the same vehicle at 50.
Correction: you're right and I'm wrong. KE does increase with the square of speed but you have to subtract 50^2 from 70^2 so at 70 KE is slightly less than double that at 50.
My brain hurts
http://www.porsche-code.com/PP37WLA6, a Dolomite Silver S, collected from Stockport OPC on Valentine's Day 2023, after a 399 day wait.
Ex.: Gen2 S, Volcano grey 1/9/19 - 3/2/23 & 39,235 Smiles, RIP
Ex.: Gen2 S, Volcano grey 1/9/19 - 3/2/23 & 39,235 Smiles, RIP
Yeah, exactly right.On-Track wrote: ↑Sun Nov 28, 2021 9:42 amI qualified from university 52 years ago so memories are more dark than light . Thanks for the formula correction but as KE increases with the square of speed I still think my multiplier is correct.Wil wrote: ↑Sat Nov 27, 2021 9:37 pmThis isn’t correct btw.On-Track wrote: ↑Sat Nov 27, 2021 11:44 am The Ferodo information was posted to support Rarecolour's argument. Unfortunately it doesn't, it recommends braking from 50mph to 20mph.
One of the basic laws of physics is E=M(C squared) where E is energy, M= Mass and C=velocity. So a mass (in this case a Macan) travelling at 70mph has 400 times the kinetic energy as one travelling at 50mph. The brakes use friction to convert this energy into heat. Ferodo warn that excessive heat can cause irreversible changes to the pad material.
Rarecolour would seem to be right about the initial bedding in but wrong about the speeds involved.
In E=MC^2 C is the speed of light not the speed of a macan.
Kinetic energy is 1/2 mv^2. So @70 you’ve about double the energy of the same vehicle at 50.
Correction: you're right and I'm wrong. KE does increase with the square of speed but you have to subtract 50^2 from 70^2 so at 70 KE is slightly less than double that at 50.
My brain hurts
Essentially what this comes down to is that 7^2 is 49 and 5^2 is 25. So it’s about double, if you ignore the effects of drag, which also squares with speed….
Car Connect is primarily the latter, but the car connect app does have a location screen to show you where the car is.
The additional Vodapone tracking service adds Vodapone notifying if the car moves without one of the tracker cards present in the car
2019 Macan S Porsche code PKW8WKI8
-
- Similar Topics
- Replies
- Views
- Last post
-
- 16 Replies
- 4058 Views
-
Last post by Neil1911